![](media/image1.png)[\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_]{.underline}

**The Dow Chemical Company**

Midland, Michigan 48674

USA

April 29, 2008

Division of Dockets Management (HFA-305)

Food and Drug Administration

5630 Fishers Lane, Room 1061

Rockville, MD 20852

**Re: [Docket No. FDA-2008-N-0040 (formerly Docket No. 2006N-0168),
"Food Labeling: Revision of Reference Values and Mandatory
Nutrients"]{.underline}**

Dear Sir or Madam:

Attached are the comments of The Dow Chemical Company. These comments
focus on the issues related to dietary fiber.

Sincerely,

![](media/image2.wmf){width="1.7493055555555554in"
height="0.4583333333333333in"}

Mark Duvall

Managing Counsel

\(989\) 638-4980

<mnduvall@dow.com>

Attachment

**Before the Food and Drug Administration**

**Docket No. FDA-2008-N-0040**

**(formerly Docket No. 2006N-0168)**

**"Food Labeling:**

**Revision of Reference Values and Mandatory Nutrients"**

**Comments of The Dow Chemical Company**

> Mark Duvall
>
> Managing Counsel
>
> April 29, 2008

TABLE OF CONTENTS

Page

EXECUTIVE SUMMARY [1](#__RefHeading___Toc197220648)

INTRODUCTION [2](#__RefHeading___Toc197220649)

DISCUSSION [3](#__RefHeading___Toc197220650)

I. FDA's Approach Until Now -- Exclusive Reliance on Analytical Methods
[3](#__RefHeading___Toc197220651)

A. 1987 Rulemaking [3](#__RefHeading___Toc197220652)

B. 1993 Rulemaking [3](#__RefHeading___Toc197220653)

C. Inaction Since 1993 [4](#__RefHeading___Toc197220654)

D. Status of Methylcellulose and HPMC as Dietary Fiber Under the Current
FDA Approach [5](#__RefHeading___Toc197220655)

II\. Problems With an Analytical Method Approach to Defining "Dietary
Fiber" [7](#__RefHeading___Toc197220656)

A. Demand on FDA Resources [7](#__RefHeading___Toc197220657)

B. Exclusion of Food Components That Have the Physiological Effects
Associated With Dietary Fiber [7](#__RefHeading___Toc197220658)

C. Adverse Public Health Impact of Excluding Food Components That Have
The Physiological Effects Commonly Associated With Dietary Fiber
[9](#__RefHeading___Toc197220659)

D. Putting the Cart Before the Horse [10](#__RefHeading___Toc197220660)

III\. FDA Should Not Limit Dietary Fiber to Intrinsic and Intact
Plant-Made Materials [12](#__RefHeading___Toc197220661)

A. That Limitation Would Exclude Some Food Components Now Considered to
be Dietary Fiber [12](#__RefHeading___Toc197220662)

B. That Limitation Is Contrary to the Trend in Scientific Thinking
[13](#__RefHeading___Toc197220663)

C. Characterizing Other Food Components as "Functional Fiber" Would Not
Encourage Their Consumption [14](#__RefHeading___Toc197220664)

D. The Science Basis for This Limitation Is Inadequate
[15](#__RefHeading___Toc197220665)

E. The Limitation Would Be Impossible to Establish Analytically
[16](#__RefHeading___Toc197220666)

F. The Limitation Would Be Inconsistent With How Other Nutrients Are
Characterized [16](#__RefHeading___Toc197220667)

IV\. FDA Should Adopt a Definition Based on Physiological Effects
[17](#__RefHeading___Toc197220668)

A. Definitions of "Dietary Fiber" [17](#__RefHeading___Toc197220669)

B. Key Issues in Definitions of "Dietary Fiber"
[17](#__RefHeading___Toc197220670)

C. FDA Should Adopt a Definition Based on Physiological Effects
[18](#__RefHeading___Toc197220671)

1\. Such a Definition Would Reflect Current Scientific Thinking
[18](#__RefHeading___Toc197220672)

2\. Types of Physiological Effects Commonly Associated With Dietary
Fiber
...........................................[18](#__RefHeading___Toc197220673)

3\. Not All Dietary Fiber Components Should Have to Have All the
Physiological Effects [20](#__RefHeading___Toc197220674)

4\. Methylcellulose and HPMC Have Physiological Effects Commonly
Associated With Dietary Fiber [21](#__RefHeading___Toc197220675)

D. FDA Should Rely on Its Existing Guidance for Substantiation of
Structure/Function Claims to Establish the Physiological Effects of
Dietary Fiber Components [22](#__RefHeading___Toc197220676)

E. Dietary Fiber Components Should Be Measured Primarily Through AOAC
Methods, Although Some Additional Work May Be Needed
[24](#__RefHeading___Toc197220677)

CONCLUSION [26](#__RefHeading___Toc197220678)

APPENDIX: Recent Proposed or Official Definitions of "Dietary Fiber"

[]{#__RefHeading___Toc197220648 .anchor}**[EXECUTIVE
SUMMARY]{.underline}**

FDA's current approach of relying on ethanol-based analytical methods to
determine the amount of dietary fiber in food has several disadvantages:

-   It means that the limited group of analytical methods recognized by
    FDA is out of date until FDA goes through notice-and-comment
    rulemaking to update the list.

-   This approach excludes some food components which have some or all
    of the physiological effects commonly associated with dietary fiber.

-   This exclusion has an adverse public health impact because the
    public will not be encouraged to purchase foods containing such
    excluded food components. While the excluded food components may be
    characterized as "other carbohydrates", that description (and others
    that have been suggested) does not encourage the public to consume
    foods containing them the way that characterizing them as "dietary
    fiber" would.

-   The approach is essentially arbitrary, where "dietary fiber" is
    whatever is quantified by certain analytical methods, rather than
    selecting methods which quantify food components which have the
    physiological effects commonly associated with dietary fiber.

Accordingly, FDA should take a different approach to quantifying dietary
fiber.

FDA should not adopt a definition of "dietary fiber" that is limited to
intrinsic and intact plant-made materials, such as the proposed
Institute of Medicine definition, because:

-   This approach would exclude from the category of dietary fiber some
    food materials regarded as dietary fiber under FDA's current
    approach.

-   Limitation of dietary fiber to intrinsic and intact plant-made
    materials is contrary to the trend in scientific thinking, which
    recognizes that other food components have some or all of the
    physiological effects commonly associated with dietary fiber.

-   Characterizing such other food components as "functional fiber"
    would not have the desirable effect of encouraging the public to
    consume foods containing them.

-   The scientific basis for concluding that plant-made materials will
    have different physiological effects than "functional fiber" has not
    been demonstrated through experimental evidence.

-   For food containing both plant-made materials and "functional
    fiber", it is impossible analytically to distinguish between the two
    in quantifying the plant-made materials.

-   This approach would be inconsistent with how other nutrients are
    characterized, in that no other nutrient is limited to intrinsic and
    intact plant-made material.

FDA should adopt a definition of "dietary fiber" that is based on
physiological effects commonly associated with dietary fiber.

-   Physiological effects are the reason that consumption of dietary
    fiber is desirable.

-   The physiological effects should include indigestibility in the
    small intestine and at least some additional effects commonly
    associated with dietary fiber, such as reduction of blood
    cholesterol levels and reducing post-prandial blood glucose or
    insulin levels.

-   Any particular component of dietary fiber should not be required to
    have all those physiological effects.

-   Substantiation of these physiological effects should follow FDA's
    guidance on the substantiation of structure/function claims. FDA
    should not have to review that substantiation.

-   Quantification of dietary fiber components should be made using AOAC
    methods, which may need some additional work to deal with potential
    overlaps.

    []{#__RefHeading___Toc197220649
    .anchor}**[INTRODUCTION]{.underline}**

The Dow Chemical Company ("Dow")[^1] welcomes the opportunity to comment
on this advance notice of proposed rulemaking ("ANPR").[^2] Dow's
comments are limited to issues related to dietary fiber. Among other
products, Dow manufactures methylcellulose and
hydroxypropylmethylcellulose ("HPMC"), two modified celluloses
(indigestible polysaccharides) that would be affected by the dietary
fiber aspects of the ANPR.[^3]

Section II.C.11 of the ANPR asked whether FDA should retain its reliance
on analytical methods to determine dietary fiber content, or whether
instead it should adopt definitions of "dietary fiber" based on its
source and of "functional fiber" based on physiological effects, and
where methodology would be a secondary issue for both terms. In
particular, FDA asked about the definition proposed in 2001 by a panel
of the Institute of Medicine ("IOM").[^4] As FDA is aware, these and
related questions are under active debate globally.

[]{#__RefHeading___Toc197220650 .anchor}**[DISCUSSION]{.underline}**

[]{#__RefHeading___Toc197220651 .anchor}**I. [FDA's Approach Until Now
-- Exclusive Reliance on Analytical Methods]{.underline}**

Over the years, FDA has primarily dealt with dietary fiber through
reference to particular analytical methods, rather than through a
definition. In effect, this reliance has defined "dietary fiber" as
whatever those analytical methods quantify. Reliance on particular
methods raises concerns that more appropriate methods are excluded.
FDA's actions have shown the limits of a strictly methodological
approach to dietary fiber.

[]{#__RefHeading___Toc197220652 .anchor}**A. [1987
Rulemaking]{.underline}**

FDA first addressed how to characterize dietary fiber in its 1987
rulemaking on nutrition labeling for the calorie content of food. To
enable food manufacturers to avoid including the calorie content of
nondigestible dietary fiber, FDA directed that the amount of dietary
fiber should be determined using the Association of Official Analytical
Chemists (now AOAC International ("AOAC")) method "Total Dietary Fiber
in Foods, Enzymatic Gravimetric Method, First Action" (now AOAC Official
Method 985.29). Commenters suggested that the final rule be worded so as
to ensure that other more appropriate methods were not excluded from use
as they become available and validated. FDA responded by saying it was
only adopting the one method at that time, but:

> The agency agrees, however, that other appropriate methods for
> determining nondigestible dietary fiber should also be adopted
> provided they have been validated by scientific procedures acceptable
> to FDA for corroborating the reliability of chemical methodologies.
> Therefore, when a new method has been validated, FDA will follow
> notice and comment rulemaking procedures (see 21 CFR Part 10) to amend
> the regulation to reflect the new method.[^5]

[]{#__RefHeading___Toc197220653 .anchor}**B. [1993
Rulemaking]{.underline}**

The Nutrition Labeling and Education Act of 1990 ("NLEA") directed FDA
to provide by regulation for inclusion of information on food labels
about dietary fiber, among other things.[^6] FDA subsequently adopted
requirements for labeling of dietary fiber content.[^7] In doing so, FDA
again referred to the methods of AOAC. In a proposed rule it had
specified that dietary fiber was to be determined by the "Total Dietary
Fiber in Foods, Enzymatic Gravimetric Method", i.e., AOAC Official
Method 985.29. Commenters raised concerns about the limitations of that
method, and FDA ultimately did not require its use.[^8] Rather, it
required use of "appropriate" methods in the "Official Methods of
Analysis of the AOAC International", 15^th^ Ed. (1990), or, "if no AOAC
method is available or appropriate, by other reliable and appropriate
analytical procedures."[^9] It concluded:

> With the currently available AOAC methods for dietary fiber and its
> components, FDA believes that suitable methodology exists for the
> analysis of dietary fiber for nutrition labeling purposes. Since the
> issuance of the supplementary proposal, two additional methods for
> dietary fiber have been accepted by the AOAC, based upon the
> collaborative data. One new method (AOAC 15, 991.43) permits the
> discrete analysis of total dietary fiber and of each subcomponent,
> i.e., soluble and insoluble dietary fiber.[^10]

In its 1993 rulemaking FDA recognized that its reliance on particular
methods systematically excluded certain materials from being classified
as "dietary fiber", without regard to their role in the body:

> Regarding the comment on the appropriateness of including low
> molecular weight bulking agents in dietary fiber, in the absence of a
> consensus on a chemical definition for dietary fiber, the available
> analytical methods dictate classification of such ingredients. Some
> manufactured low molecular weight, carbohydrate based, bulking agents,
> such as polydextrose, do not analyze as dietary fiber in the official
> AOAC methods for measuring dietary fiber. Such food ingredients, while
> not reported as dietary fiber in nutrition labeling, would be included
> in total carbohydrate and reported as "other carbohydrate."[^11]

Thus, FDA recognized that the absence of a definition of "dietary fiber"
based on physiological effects leads to the exclusion of some food
components from the desirable category of "dietary fiber" and relegates
them to the less-desirable category of "other carbohydrate" or, to use
the IOM term, "functional fiber". In the ANPR, FDA is asking whether it
should change this situation.

[]{#__RefHeading___Toc197220654 .anchor}**C. [Inaction Since
1993]{.underline}**

By restricting its recognition of dietary fiber to food components
measured using the then-current AOAC methods, FDA limited its ability to
recognize advances in analytical methods and scientific understanding of
dietary fiber. It has not updated that provision, so the 1990 edition
remains the official set of methods for determining dietary fiber. Today
the current version of the AOAC Manual is the 18^th^ edition, 2^nd^
revision, issued in 2007.[^12] Thus, the FDA-recognized methods are 17
years out of date.

As a result, FDA has not recognized even widely-accepted modifications
to AOAC Official Method 985.29. For example, two modifications were
adopted in 1995: AOAC Official Method 991.42, "Insoluble Dietary Fiber
in Foods and Food Products -- Enzymatic-Gravimetric Method, Phosphate
Buffer" and AOAC Official Method 993.16, "Soluble Dietary Fiber in Foods
and Food Products -- Enzymatic-Gravimetric Method, Phosphate
Buffer".[^13]

Of note is that in 1998 FDA recognized the 1995 modification of AOAC
Official Method 991.43, from the 16^th^ edition, for the purpose of a
fiber-based health claim,[^14] but it has not recognized any edition
other than the 15^th^ for purposes of quantifying dietary fiber for
nutrition labeling purposes.

Rather than go through notice-and-comment rulemaking, as promised in
1987, FDA has made food manufacturers rely on the catch-all provision,
"other reliable and appropriate analytical procedures", to cover new
methodological and technological developments related to dietary fiber.

[]{#__RefHeading___Toc197220655 .anchor}**D. [Status of Methylcellulose
and HPMC as Dietary Fiber Under the Current FDA Approach]{.underline}**

Two good examples of the limitations of the current FDA approach to
dietary fiber are methylcellulose and HPMC. They are detected by the
methods in the 15^th^ edition of the AOAC Manual, and thus they are both
considered to be dietary fiber. Those methods poorly quantify the amount
of methylcellulose and HPMC present, however. AOAC recently accepted as
First Action a modification of the methods in the 15^th^ edition to
better quantify these materials. FDA should update its recognition of
acceptable dietary fiber analytical methods to include this modified
method. In the absence of such recognition, food manufacturers using
this modified method must depend on the general language in FDA's
nutrition labeling regulation allowing use of "other reliable and
appropriate analytical procedures" where the methods in the 15^th^
edition are not "appropriate".

Methylcellulose and HPMC are modified celluloses. To make them, natural
cellulose (which is universally regarded as dietary fiber) is chemically
modified, without alteration of the natural cellulose backbone, but with
addition of functional groups to some of the hydroxyl ends of the
polysaccharide. This change affects their properties, notably by
changing the insoluble cellulose into soluble modified cellulose. Yet
the 1,4-β-glycosidic bond in the cellulose backbone remains intact,
preserving the small intestine indigestibility property of the modified
cellulose.

The dietary fiber methods in the 15^th^ edition of the AOAC Manual are
known as enzymatic-gravimetric methods. They begin with enzymatic
digestion sequence of the test material. This simulates digestion in the
small intestine, leaving behind only indigestible material, since
indigestibility in the small intestine is generally regarded as a
defining characteristic of dietary fiber. The remaining material is then
treated with an approximately 80% heated solution of ethanol. Material
that is soluble in ethanol stays in solution, but material that is
insoluble in ethanol precipitates out. The precipitate is then weighed,
and that amount is deemed to be the quantity of dietary fiber.

Methylcellulose and HPMC are polymers with varying molecular weights and
viscosities. Since they are derived from natural cellulose that has been
modified with some hydrophobic groups, such as methyl or hydroxypropyl
groups, they are partially soluble and partially insoluble in ethanol
(such as 80% blend of ethanol in water). Their solubility in aqueous
ethanol increases as the test temperature rises. Accordingly, some
quantities of methylcellulose and HPMC precipitate out and are available
to be weighed.[^15] This result accounts for the following statement
from the American Association of Cereal Chemists (now AACC
International):

> Modified celluloses such as methyl cellulose and hydroxypropylmethyl
> cellulose have long been accepted as dietary fiber simply because they
> are quantitated by the Official dietary fiber methods utilized since
> the mid 1980s.[^16]

On the other hand, the variability and poor quantification using the
15^th^ edition methods have led the IOM to make this statement:

> Several manufactured carbohydrates, such as methylcellulose ..., are
> also resistant to human enzymatic hydrolysis. This would classify them
> as fiber under many definitions; however, they are not routinely
> analyzed as dietary fiber because they do not precipitate in
> ethanol.[^17]

Recognizing this limitation of the 15^th^ edition methods, Dow developed
a modification to those methods, now accepted by AOAC as Official Method
2006.08.[^18] The enzymatic digestion step is conducted as in AOAC
Official Method 991.43. Digestate solutions are then refrigerated (to
fully hydrate the methylcellulose and HPMC), filtered, and analyzed by
size-exclusion liquid chromatography. This method showed acceptable
precision and reproducibility to gain acceptance by AOAC as First Action
in 2006.[^19] It has been included in lists of AOAC methods for dietary
fiber.[^20]

Clearly, the methods in the 15^th^ edition detect methylcellulose and
HPMC, and thus these food materials are considered dietary fiber under
the current FDA approach. Since those methods quantify them poorly,
however, FDA should act to recognize AOAC Official Method 2006.08 as an
additional acceptable method for quantifying dietary fiber. (For
example, FDA could update its regulation incorporating by reference the
15^th^ edition to refer to the current edition as of the time of the
final rule.) Until FDA does go through notice-and-comment rulemaking to
do so, however, food manufacturers must rely on the language in FDA's
nutrition labeling regulation allowing use of "other reliable and
appropriate analytical procedures" where no AOAC method (in the 15^th^
edition) is "appropriate".[^21] Given the inaccuracy of the 15^th^
edition methods in quantifying methylcellulose and HPMC, it is fair to
say that the 15^th^ edition contains no "appropriate" method for them.
Official Method 2006.08 is both "reliable", as determined by AOAC, and
"appropriate", since it is specific to methylcellulose and HPMC.

This need for FDA to update its regulations to take developments in
analytical methodology into account illustrates one limitation of FDA's
current approach to dietary fiber. Others are discussed in the next
section.

[]{#__RefHeading___Toc197220656 .anchor}**II. [Problems With an
Analytical Method Approach to Defining "Dietary Fiber"]{.underline}**

[]{#__RefHeading___Toc197220657 .anchor}**A. [Demand on FDA
Resources]{.underline}**

As discussed above, one problem with an analytical method approach is
that FDA puts itself in the position of either being technologically
behind, as it is today, or else having to devote some of its limited
administrative resources to notice-and-comment rulemaking periodically
to update its incorporation by reference of AOAC Official Methods.

[]{#__RefHeading___Toc197220658 .anchor}**B. [Exclusion of Food
Components That Have the Physiological Effects Associated With Dietary
Fiber]{.underline}**

Of greater concern is that an analytical method approach to defining
"dietary fiber" excludes from that definition food components that have
physiological effects commonly associated with dietary fiber. As FDA has
recognized,

> The available analytical methods are generally poor predictors of the
> physiological effects of various dietary fibers.[^22]

The IOM report noted that many definitions of "dietary fiber" based on
physiological effects include fibers that an ethanol-based analytical
method approach would exclude:

> Because many current definitions \[of dietary fiber\] are based on
> methods involving ethanol precipitation, oligosaccharides and fructans
> that are endogenous in foods, but soluble in ethanol, are not analyzed
> as dietary fiber. Yet endogenous human enzymes do not digest fructans
> ...; thus they are included in many definitions (Table 3) ....
>
> No uniform approach has been developed to resolve the issue of fiber
> carbohydrates that do not precipitate in ethanol, even though many of
> these naturally occurring, hydrolyzed, or manufactured components are
> not analyzed as fiber but are considered to be fiber by many
> definitions. Recent analytical efforts have been directed toward the
> measurement of a specific carbohydrate or product, such as
> polydextrose or fructooligosaccharides. This individual approach has
> resulted in a proliferation of methods, some of which would overlap if
> applied to a product containing several manufactured or modified
> carbohydrates.[^23]

One example of the individual approach is an analytical method for
methylcellulose and HPMC, AOAC Official Method 2006.08, discussed above.

FDA scientists themselves have acknowledged the inappropriate
limitations of ethanol-based analytical methods:

> We have reexamined the widely accepted AOAC Official Method 985.29 for
> total dietary fiber. We have focused specifically on the ethanol
> precipitation step of this method, because use of this step excludes
> many components recognized as having the physiologic effects of
> dietary fiber. With method 985.29, the digestible carbohydrates are
> hydrolyzed enzymatically. Addition of ethanol (4 to 1) is then used to
> precipitate soluble fiber. **This step is problematic**, because some
> oligosaccharides such as fructooligosaccharides (FOS) are not
> precipitated. Therefore, FOS are not considered as dietary fiber.
> **However, FOS and similar components are not digested in the upper GI
> track and should be considered as dietary fibers.**[^24]

This exclusion of some food components solely based on methodological
considerations is arbitrary. The purpose of identifying the dietary
fiber content in food is to allow consumers to make informed choices,
and, hopefully, to increase consumption of dietary fiber due to its
physiological effects. That purpose can be served by a broader class of
food components than those which precipitate in ethanol.

[]{#__RefHeading___Toc197220659 .anchor}**C. [Adverse Public Health
Impact of Excluding Food Components That Have The Physiological Effects
Commonly Associated With Dietary Fiber]{.underline}**

Most significantly, an analytical method approach can have a significant
negative impact on public health. It excludes food components that have
physiological effects commonly associated with dietary fiber (i.e., the
reasons why it is desirable for the American public to consume more
dietary fiber).

One commenter has explained with respect to different approaches to
defining "dietary fiber":

> As the substances included within these two approaches to definition
> \[are\] not the same, the potential public health implications
> associated with each of them will also differ. \[Dietary fibre's\]
> prominent position in guidelines and the associated health messages
> has led to good consumer recognition of the dietary fibre term.
> Therefore, dietary fibre is very much a public health term, and a
> foremost consideration must be to ensure that consumers can interpret
> dietary fibre values and any associated nutrition claims in a manner
> that assists them with informed choice in diet selection, and that
> does not present the opportunity for misrepresentation of
> products.[^25]

For those materials excluded from the definition of "dietary fiber",
other terms have been suggested. FDA currently defines "other
carbohydrate" as the difference between total carbohydrate and the sum
of dietary fiber, sugars, and (if indicated) sugar alcohol.[^26] The IOM
has suggested the term "added fiber"[^27] and "functional fiber".[^28]
None of those terms conveys to the public the health benefits associated
with the term "dietary fiber".

The key here is effective communication to consumers. "Dietary fiber" is
now well understood to refer to food components having certain
physiological effects. Limiting that term to exclude some food
components having those effects, and calling those excluded components
by an unfamiliar and less clear name, has a negative effect on the
consumption of foods containing those excluded components.[^29] As the
British Nutrition Foundation ("BNF") has argued:

> BNF believes that it is of major public health interest to extend the
> definition of fibre to effectively classify a group of indigestible
> food components with known health benefits in a way that is useful for
> food manufacturers and health professionals to communicate to
> consumers ....
>
> \[I\]n terms of consumer communication, efforts to increase fibre
> intakes in the UK will be facilitated by a single, all inclusive
> definition of 'dietary fibre' for use in food labelling.[^30]

Continued reliance on analytical methods that exclude some food
components that have physiological benefits commonly associated with
dietary fiber means that those excluded components will not receive
recognition for their physiological benefits. There will be less demand
for them, and thus the public is likely to consume less of them than it
would if they were included in the definition of "dietary fiber", at a
time when there is widespread recognition of the need for the public to
consume more dietary fiber.

Like some of the other food components excluded for methodological
reasons, methylcellulose and HPMC are used primarily in processed food.
While arguably fresh food may provide superior health benefits as
compared with processed food, the reality is that Americans are
increasingly consuming processed food. Accordingly, in making selections
among processed foods, consumers would be helped by knowing that the
physiological benefits of dietary fiber are available from some
processed foods and not others. If materials such as methylcellulose and
HPMC are not included in dietary fiber, however, consumers will not
recognize that processed foods containing them offer the physiological
benefits of dietary fiber, since the names "other", "additional", or
"functional" fiber do not convey that information.

[]{#__RefHeading___Toc197220660 .anchor}**D. [Putting the Cart Before
the Horse]{.underline}**

Back in the 1980s, when FDA adopted an analytical method approach to
quantifying dietary fiber, there was general equivalence between what
was understood to be dietary fiber and the available analytical methods.
Since then, there has been a divergence. Understanding of what dietary
fiber is has expanded greatly, and analytical methods have tried to keep
up with that expanded understanding. ILSI Europe has explained:

> The understanding of the physiological significance of substances
> defined as dietary fibre and thus the concept of dietary fibre has
> progressed considerably over the past ten years. It is now recognized
> that it encompasses a much broader range of substances than was
> originally acknowledged.[^31]

While it is important to be able to quantitate food components
determined to qualify as dietary fiber, having analytical methods for
that purpose is of necessity secondary to determination of what
qualifies as dietary fiber. A purely analytical method approach to
defining dietary fiber makes the analytical method primary, by defining
"dietary fiber" as whatever particular methods can quantitate. In other
words, it puts the cart before the horse.

Thus, the key task before FDA is to identify which food components
should qualify as dietary fiber; identification of analytical methods to
quantitate those components is secondary. As some commentators have
said:

> An important aspect of nutrition is the requirement to describe
> clearly defined nutritional components. To this end, methods of
> analysis are a secondary issue, where suitability should be assessed
> on how well they measure the intended component. This principle should
> apply to the definition and measurement of every nutrient, but for
> dietary fibre there has been an inappropriate emphasis on methodology
> to the extent that some proposed definitions have been based on the
> material recovered by a particular analytical procedure. This is an
> unacceptable situation with respect to describing food composition.
> Analytical methods should be 'fit for purpose', which for dietary
> fibre can be assessed by the following criteria: (1) whether the
> material described in the respective stated aims of methods are
> suitable as a measure of dietary fibre; (2) the degree to which the
> methods actually measure the material described within their
> respective stated aims.[^32]
>
> The current regulatory situation in the US, as well as in a number of
> other nations, with regard to dietary fiber labeling is arbitrary due
> to its reliance on methodology as opposed to being based on an
> accurate definition.[^33]

There is support in the NLEA legislative history for the proposition
that Congress intended FDA to consider which food components should
qualify as particular nutrients, and then ensure that there are adequate
analytical methods to measure those components:

> In implementing the nutrition labeling requirements, the Secretary of
> Health and Human Services ("the Secretary") may provide definitions of
> the nutrients which are listed in section 403(q)(1)(D) or required to
> be listed under 403 (q)(2) \[i.e., including dietary fiber\]. **The
> definitions would give manufacturers a precise description of the
> nutrients (such as saturated fat) so that they will know the type of
> analysis to conduct on the food.** Definitions of nutrients must be
> consistent with scientific principles. Thus, the Secretary may exclude
> certain forms of particular nutrients if there is a sound scientific
> reason. For example, in the course of considering this bill, the
> Committee received testimony that **certain saturated fatty acids,
> such as stearic acid, do not increase blood cholesterol and therefore
> should not be counted as saturated fat for purposes of nutrition
> labeling.** Under the bill, the Secretary has the discretion to define
> saturated fat in a way that excludes specified fatty acids, such as
> stearic acid, if the Secretary determines that such an exclusion is
> consistent with the public health and is based on sound scientific
> principles.[^34]

Just as stearic acid could be excluded from the definition of "saturated
fat", so modified celluloses and other food components should be
included or excluded from the definition of "dietary fiber". The basis
for inclusion or exclusion should be "sound scientific principles"
relating to "public health", such as whether the component at issue
impacts health the way that the nutrient name is understood to impact
health. The reason Congress advised FDA that it could exclude stearic
acid from the definition of "saturated fat" is because saturated fat is
commonly understood to increase blood cholesterol and stearic acid does
not have that health effect.

Similarly, modified celluloses and other food components not quantified
accurately through ethanol-based analytical methods may impact health in
the same way that dietary fiber is understood to do so. On that basis
FDA should consider including them in the definition of "dietary fiber".
Only once the specific food components to be quantified have been
identified through definitions should the availability of analytical
methods to quantitate those components be considered.

[]{#__RefHeading___Toc197220661 .anchor}**III. [FDA Should Not Limit
Dietary Fiber to Intrinsic and Intact Plant-Made
Materials]{.underline}**

[]{#__RefHeading___Toc197220662 .anchor}**A. [That Limitation Would
Exclude Some Food Components Now Considered to be Dietary
Fiber]{.underline}**

FDA should certainly not adopt a definition of "dietary fiber" which is
narrower than the implicit one it now has, which considers to be dietary
fiber that which is determined through the dietary fiber methods in the
15^th^ edition of the AOAC Manual (or, if none is appropriate, through
other reliable and appropriate methods). The current approach is already
too narrow, as discussed above. FDA should not narrow it further.

The first section of these comments explained that methylcellulose and
HPMC are considered to be dietary fiber under the current FDA approach.
Although derived from cellulose (a plant-made material), they are not
"intrinsic and intact" plant-made materials, and so the IOM definition
would exclude them from the category of dietary fiber. They are only
examples of food components that would no longer be considered dietary
fiber if FDA were to adopt the IOM definition.

Another example is chitosan, a derivative of chitin. This is a
polysaccharide that is derived from animals (from shrimps and other sea
crustaceans). It can be characterized as dietary fiber according to the
dietary fiber methods in the 15^th^ edition of the AOAC Manual. More
broadly, as recognized by the IOM:

> Polysaccharides from animals, yeast, bacteria, and agricultural
> by-products may all be similar in chemical structure to some
> components that make up the fiber found in plant foods. Although there
> has been no thorough evaluation, it can be assumed that animal-derived
> carbohydrate polymers analyze as dietary fiber by existing fiber
> methods. Definitions of dietary fiber thus include nondigestible
> animal carbohydrates (Table 3) in one of two ways: (1) they are part
> of dietary fiber for all definitions that are based on methods that
> precipitate polysaccharides with ethanol or measure monosaccharide
> constituents in the fiber residue, or (2) they are included because
> the definition does not specify plant components.[^35]

[]{#__RefHeading___Toc197220663 .anchor}**B. [That Limitation Is
Contrary to the Trend in Scientific Thinking]{.underline}**

The IOM proposed definition is limited to plant-made materials:

> *Dietary Fiber* consists of nondigestible carbohydrates and lignin
> that are intrinsic and intact in plants.[^36]

Similarly, an expert group within the FAO/WHO has proposed a definition
limited to plant-made materials:

> Dietary fibre consists of intrinsic plant cell wall
> polysaccharides.[^37]

In contrast to these proposed definitions, several other recent
definitions are not limited to plant-made materials, but rather
explicitly or implicitly include manufactured food components. See in
the Appendix to these comments the definitions of:

-   The Association of American Cereal Chemists

-   The Codex Alimentarius Commission, Committee on Nutrition and Foods
    for Special Dietary Uses

-   The European Food Safety Authority, Scientific Panel on Dietetic
    Products, Nutrition and Allergies

-   Health Council of the Netherlands

-   Agence Française de Securité Sanitaire des Aliments

-   Food Standards Australia New Zealand

Limitation of the term "dietary fiber" to plant-made materials is
contrary to the trend in scientific thinking, which has been to include
food components that are not plant-made in the definition, and to base
the definition on physiological effects. FDA should pay special
attention to the vehement opposition by many nations and Codex observers
to the proposed definition of the FAO/WHO expert group that would have
limited dietary fiber to "intrinsic plant cell wall polysaccharides".
These comments are collected in a recent Codex document.[^38]

As Japan stated in opposing the expert group's proposed definition:

> It has not given due consideration to the history of the research
> regarding physiological effects and/or the definition of dietary
> fibre.[^39]

Similarly, the Institute of Food Technologies ("IFT") has declared:

> In IFT's viewpoint, the proposals presented \[by the FAO/WHO expert
> group\] ignore the substantial progress in scientific understanding of
> the role of fibre in human nutrition and the mechanisms of its actions
> and are, therefore, scientifically unfounded and will not
> substantially improve health messages related to the consumption of
> fruits, vegetables and wholegrain foods.[^40]

[]{#__RefHeading___Toc197220664 .anchor}**C. [Characterizing Other Food
Components as "Functional Fiber" Would Not Encourage Their
Consumption]{.underline}**

The IOM would not totally ignore food components having the
physiological effects commonly associated with dietary fiber that are
not intrinsic and intact plant-made materials; it would call them
"functional fiber":

> *Functional Fiber* consists of isolated, nondigestible carbohydrates
> that have beneficial physiological effects. *Total Fiber* is the sum
> of *Dietary Fiber* and *Functional Fiber*.[^41]

But this term is not well-understood or accepted by the public.
Consumers would not regard functional fiber as essentially equivalent in
physiological benefits to dietary fiber. The term is scarcely more
inviting to the public than is FDA's current term, "additional
carbohydrates".

This distinction between dietary fiber and functional fiber would have
about the same adverse public health impact as FDA's current reliance on
ethanol-based analytical methods to quantify dietary fiber. (Please
refer to Section II.C of these comments.) Consumers would tend not to
recognize that processed foods (which are typically the kinds of foods
to which functional fiber would be added) having relatively higher
levels of functional fiber are better for them to consume than those
with lower levels. Those interested in dietary fiber levels would tend
to ignore functional fiber altogether.

[]{#__RefHeading___Toc197220665 .anchor}**D. [The Science Basis for This
Limitation Is Inadequate]{.underline}**

The evidentiary basis for restricting the definition of "dietary fiber"
to intrinsic and intact plant-made materials only is limited to
epidemiological studies, which are inherently limited in their ability
to detect the contribution of individual food components. Moreover,
those epidemiology studies did not consider the impact of eating
processed foods high in what the IOM calls functional fiber.

These points have been made by the International Council of Grocery
Manufacturers in comments on the proposed definition of the FAO/WHO
expert group:

> While there may be theoretical grounds for believing that "intrinsic"
> fibre consisting of plant cell wall material may have different
> effects from "added" fibre, there currently is no sound scientific
> basis demonstrating that "intrinsic" dietary fibre has different
> effects from "added" dietary fibre in foods. The arguments advanced by
> the FAO/WHO consultation appear to be based on speculation from
> associations found in epidemiological studies rather than direct
> experimental evidence. The fact that the reported intake of foods
> naturally high in fibre is associated with a lower risk of several
> non-communicable diseases is not good enough evidence for the
> beneficial effect of "intrinsic" dietary fibre over added (extrinsic)
> fibre if studies addressing added fibre are not considered and because
> different patterns of food also reflect different lifestyle patterns
> (smoking, exercise, drinking habits, socioeconomic status) which are
> associated with health outcomes.[^42]

Other critiques of the evidentiary basis for this proposed definition
are available.[^43]

[]{#__RefHeading___Toc197220666 .anchor}**E. [The Limitation Would Be
Impossible to Establish Analytically]{.underline}**

Moreover, there is an important analytical reason not to limit dietary
fiber to plant-made materials: It is difficult or impossible to
distinguish analytically between plant-made carbohydrates and analogous
food components which may be present in the same food product:

> \[The IOM definition\] also creates an artificial, analytically
> impossible and therefore in practice non-existing distinction between
> fibres naturally present in plant cells and those extracted from plant
> sources or synthetically produced.[^44]
>
> The panel notes that a main problem in making this differentiation in
> practice is that no analytical method differentiates between "dietary
> fibre" and "functional fibre" once they occur mixed in a food product,
> and similarly, that NSP \[non-starch polysaccharides\] from plant cell
> walls cannot be differentiated from added NSP with similar monomeric
> composition.[^45]
>
> The 1997 joint WHO/FAO expert consultation report on carbohydrates in
> human nutrition specifically recommends against the use of the terms
> extrinsic and intrinsic with regard to sugars because the body cannot
> distinguish between them physiologically.[^46]

[]{#__RefHeading___Toc197220667 .anchor}**F. [The Limitation Would Be
Inconsistent With How Other Nutrients Are Characterized]{.underline}**

Finally, as pointed out by Japan in its comments on the expert group's
proposed definition, limiting dietary fiber to intrinsic and intact
plant-made materials:

> This situation would be inconsistent with the handing of other
> nutrients (e.g., vitamins and minerals) which does not specify the
> source of the nutrients.[^47]

Thus, the balance of world opinion and experts does not support the
IOM's proposed limitation of dietary fiber to intrinsic and intact
plant-made materials.

[]{#__RefHeading___Toc197220668 .anchor}**IV. [FDA Should Adopt a
Definition Based on Physiological Effects]{.underline}**

[]{#__RefHeading___Toc197220669 .anchor}**A. [Definitions of "Dietary
Fiber"]{.underline}**

The ANPR asked if FDA should adopt the IOM definitions of "dietary
fiber" and "functional fiber". There is no reason FDA should consider
only those definitions. Review of other proposed or official definitions
can highlight the key issues in those definitions. A partial listing of
recent proposed or official definitions appears in the Appendix to these
comments.

It is clear that there is as yet no international consensus on a single
definition. Such a consensus may not be achieved for several years, if
ever. In the meantime, FDA should decide on its own definition. In
considering its definition, FDA should recognize that the trend in
expert opinion globally is to have a definition that is not limited to
plant-made materials, that is based on physiological effects, and that
is measured primarily using AOAC methods.

B.  []{#__RefHeading___Toc197220670 .anchor}**[Key Issues in Definitions
    of "Dietary Fiber"]{.underline}**

The key issues FDA should consider with respect to a definition of
"dietary fiber" include:

-   Should the definition include physiological effects commonly
    associated with dietary fiber? Dow believes that the definition
    should include such physiological effects, but should also
    recognize, as many definitions do, that each component of dietary
    fiber will not necessarily have all of those effects.

-   How should those physiological effects be established? Dow believes
    that physiological effects are analogous to structure/function
    claims and should be established in the same manner as
    structure/function claims are established (i.e., substantiation
    should required as indicated in FDA guidance for substantiating
    structure/function claims, including clinical studies, but FDA
    should not need to review the evidence).

-   How should the components of dietary fiber be quantified? Dow
    believes that the AOAC methods should be used. Some further work may
    be required to deal with the potential for double-counting where
    several methods are used to account for all the dietary fiber
    components in a food.

    []{#__RefHeading___Toc197220671 .anchor}**C. [FDA Should Adopt a
    Definition Based on Physiological Effects]{.underline}**

    []{#__RefHeading___Toc197220672 .anchor}**1. [Such a Definition
    Would Reflect Current Scientific Thinking]{.underline}**

FDA should adopt a definition of "dietary fiber" based on the
physiological effects of food components. This would reflect the trend
in scientific thinking on this issue:

> Physiological properties of dietary fibre determine its importance in
> the human body and its requirement in the human diet. Therefore, most
> scientists now agree that the definition of dietary fibre should be
> physiologically based.[^48]
>
> Clearly, a physiological basis for the definition of dietary fiber is
> necessary. If it were not for the physiological effects of dietary
> fiber, there would be no interest in the subject on the part of either
> researchers, consumers, regulators, and manufacturers .... Inclusion
> of these key physiological properties in the definition of dietary
> fiber is not only prudent, but it would be scientifically short-sided
> to exclude health effects that the body of scientific evidence
> supports.[^49]

The IOM proposed definition would limit consideration of physiological
effects to "functional fiber", which would be excluded from the term
"dietary fiber". If FDA adopts a definition of "dietary fiber" based on
physiological effects, there would be no need to adopt a supplemental
definition such as "functional fiber". Instead, all dietary fiber would
be functional.[^50]

[]{#__RefHeading___Toc197220673 .anchor}**2. [Types of Physiological
Effects Commonly Associated With Dietary Fiber]{.underline}**

Many of the definitions in the Appendix to these comments (or the
reports in which those definitions appear) identify physiological
effects that should be considered to be relevant for determination of
whether a food component is a dietary fiber. Of these,

> Non-digestibility in the small intestine is a key physiological
> characteristic of dietary fibre.[^51]

In addition to this essential physiological characteristic, other
effects have been identified repeatedly. For example:

> The interest of defining and quantifying dietary fibre in foods lies
> in the physiological effects that are associated with the consumption
> of that dietary component, which include decreased intestinal transit
> time and increased stools bulk, reducing blood and/or LDL cholesterol
> levels, and reducing post-prandial blood glucose and/or insulin
> levels, among others .... These physiological effects of dietary fibre
> are distinct from those of digestible carbohydrates.[^52]
>
> Research over recent decades has identified the following main
> physiological effects of dietary fibre: improvements in large bowel
> function, lowering of blood cholesterol, and attenuation of
> post-prandial blood glucose and insulin levels. These physiological
> effects have been incorporated into recent definitions of dietary
> fibre.[^53]
>
> Dietary fiber is the edible parts of plants or analogous carbohydrates
> that are resistant to digestion and absorption in the small intestine
> with complete or partial fermentation in the large intestine ....
> Dietary fibers promote beneficial physiological effects including
> laxation, and/or blood cholesterol attenuation, and/or blood glucose
> attenuation.[^54]
>
> Dietary fibre generally has properties such as:

-   Decrease intestinal transit time and increase stools bulk

-   Fermentable by colonic microflora

-   Reduce blood total and/or LDL cholesterol levels

-   Reduce post-prandial blood glucose and/or insulin levels.[^55]

> \[Dietary fibre\] has at least one of the following properties:

-   Increase stools production

-   Stimulate colonic fermentation

-   Reduce pre-prandial cholesterol levels

-   Reduce post-prandial blood sugar and/or insulin levels[^56]

> In general, specific types of dietary fiber have one or more of the
> following physiological effects: they accelerate the transit of food
> through the gastrointestinal tract; they increase the amount of stool;
> they favourably affect fermentation in the colon; they reduce blood
> LDL cholesterol levels; they help improve blood glucose and blood
> insulin levels.[^57]

As can be seen, there is substantial overlap in these lists of
physiological effects commonly associated with dietary fiber.

[]{#__RefHeading___Toc197220674 .anchor}**3. [Not All Dietary Fiber
Components Should Have to Have All the Physiological
Effects]{.underline}**

Of note, however, is that most definitions based on physiological
effects do not insist that a particular dietary fiber have all of the
listed effects, as is evident from terms such as "generally", "and/or",
and "at least one of". Some insist that a definition of "dietary fiber"
should not require all listed effects to be manifested by each
component:

> Therefore, it is not appropriate to state that fibre has a single all
> encompassing physiological property as these effects are dependent on
> the type of fibre in the diet.[^58]

In particular, fermentation in the colon need not be an essential
physiological effect for a food component to qualify as a dietary fiber:

> At this stage, we did not mention the colonic fermentation (complete
> or partial) of dietary fibre as mentioned in several recently proposed
> definitions (AACC, 2001; ANZFA, 2001). We consider, contrary to what
> is stated in other definitions, that a fibre (as defined above) which
> has one of the physiological effects mentioned in the definition but
> which is not fermented in the colon should not in theory be excluded
> from the definition of dietary fibre.[^59]

[]{#__RefHeading___Toc197220675 .anchor}**4. [Methylcellulose and HPMC
Have Physiological Effects Commonly Associated With Dietary
Fiber]{.underline}**

Methylcellulose and HPMC have many of the physiological effects commonly
associated with dietary fiber. Taking HPMC as an example, it:

-   Is indigestible in the small intestine[^60]

-   Lowers blood cholesterol levels in humans[^61]

-   Lowers post-prandial glucose and insulin responses in humans[^62]

-   Increases laxation and other bowel parameters[^63]

But HPMC is not fermentable in the large intestine.[^64] Nevertheless,
some expert groups explicitly consider methylcellulose and HPMC as
components of dietary fiber,[^65] or else methylcellulose and HPMC would
qualify as dietary fiber under their definitions.

Accordingly, the FDA definition should require dietary fiber components
to have at least some listed physiological effects, but not necessarily
all of them.

[]{#__RefHeading___Toc197220676 .anchor}**D. [FDA Should Rely on Its
Existing Guidance for Substantiation of Structure/Function Claims to
Establish the Physiological Effects of Dietary Fiber
Components]{.underline}**

In the official discussions of the proposed Codex definition, the United
States has expressed concern about the implications of a
physiologically-based definition on health claims and the methods for
establishing those physiological effects:

> The Delegation of the United States ... expressed its concern with the
> listing of physiological properties as such properties were not
> usually listed in the definition of nutrients and they might be
> interpreted as a justification for claims; and physiological effects
> should not be mentioned without appropriate methods to evaluate those
> effects.[^66]

Congress has addressed this issue in the NLEA. There it directed FDA to
provide for nutritional content labeling (specifically including the
level of dietary fiber) under Section 403(q) of the FFDCA, and it
required health claims to go through rulemaking under Section 403(r)(3).
These are different kinds of claims, so that nutritional content
labeling of dietary fiber, even with a physiologically-based definition,
is not a health claim.

Section 403(r)(1)(B) defines a health claim as one which:

> characterizes the relationship of any nutrient which is of the type
> required by paragraph (q)(1) \[i.e., including dietary fiber\] ... to
> be in the label or labeling of the food to a disease or a
> health-related condition ....

The NLEA legislative history gives an example of a health claim: "fiber
helps to prevent cancer". But in the very next sentence, it states:

> Although a content claim (such as "low sodium") ... may be relevant to
> a particular disease, such a claim is not a disease claim within
> 403(r)(1)(B) and therefore is not subject to 403(r)(3).[^67]

If a claim which [characterizes]{.underline} the amount of a nutrient is
not a disease (or health) claim, then clearly a statement
[of]{.underline} the amount of a nutrient in a food is not a disease (or
health) claim either.

At most, the physiological effects identified in a definition of dietary
fiber are analogous to implicit structure/function claims, which are
covered not by Section 403(r)(3), but by Section 403(r)(6). That
provision defines a structure/function claim in part as a statement
that:

> describes the role of a nutrient or dietary ingredient intended to
> affect the structure or function in humans, characterizes the
> documented mechanism by which a nutrient or dietary ingredient acts to
> maintain such structure or function, or describes general well-being
> from consumption of a nutrient or dietary ingredient.

FDA's regulation on structure/function claims reflects the same
distinction between disease (health) claims and structure/function
claims.[^68] The distinction is between maintaining normal function and
treatment or prevention of abnormal function. Dietary fiber's
physiological effects relate to maintaining normal function. If any
dietary fiber claims are made that go beyond maintaining normal
function, they would be health claims subject to Section 403(r)(3) and
FDA's health claim regulations.[^69] FDA has already determined that a
health claim relating dietary fiber to cardiovascular disease is not an
authorized health claim,[^70] and it has authorized some other health
claims related to particular dietary fiber components.[^71]

FDA has expressed concern about how physiological effects will be
established:

> Currently, there are no universally accepted methods that quantify
> such effects. Appropriate standards and controls will need to be
> agreed upon, as well as conditions under which such functions can be
> defined. *In vitro* systems will need to be developed that accurately
> reflect rate and extent of fiber fermentation. Questions of whether
> such procedures should be applied to the fiber alone or to the food
> product to which the fiber is added, and of the relationship of such
> measurements to *in vivo* effects must also be addressed.[^72]

FDA has provided guidance on the level of substantiation needed to
support a structure/function claim.[^73] That same level of
substantiation should be enough to support a claim that a food component
has some or all of the effects identified in a physiologically-based
definition of "dietary fiber". The guidance does not prescribe
particular analytical methods for establishing structure/function
claims, but relies on performance standards. The same approach would be
appropriate for establishing dietary fiber-related physiological
effects.

Just as FDA does not review the evidence for a structure/function claim,
so FDA should not have to review the evidence that a food component has
some or all of the effects identified in a physiologically-based
definition of "dietary fiber". This should limit the resource demands on
FDA. Persons claiming that a particular food component has physiological
effects listed in an official definition of "dietary fiber" or commonly
associated with dietary fiber would be subject to the FFDCA's
prohibition on misbranding.

[]{#__RefHeading___Toc197220677 .anchor}**E. [Dietary Fiber Components
Should Be Measured Primarily Through AOAC Methods, Although Some
Additional Work May Be Needed]{.underline}**

FDA and the United States have offered some comments critical of
proposed definitions which rely on physiological effects rather than
analytical methods. A key concern has been about analytical methods to
detect all the materials that have those effects:

> Specifically, the U.S. notes that currently there is no single AOAC
> method to measure total fiber content based on the proposed
> definitions. Moreover, for the draft definition in Appendix III
> \[i.e., the proposed Codex definition\], there currently is no
> validated procedure to combine methods to estimate total fiber that
> would be consistent with this definition. For example, AOAC method
> 985.29 generally excludes small molecular weight compounds and some
> resistant starches, while other methods are specific to a fraction or
> certain food matrices. Thus, the Committee may wish to consider the
> implications of not having an agreed upon validated method or a
> validated procedure for combining methods for the proposed definitions
> in determining whether, when, and how the current Codex definition
> should be revised.[^74]

This is an important issue, but FDA should recognize that the problem is
with us already. There is now widespread acceptance that some materials
qualify as dietary fiber even though they are not detectable through
ethanol-based analytical methods.

The General Referee for Dietary Fibre and Complex Carbohydrates of the
AOAC has taken the approach that specific methods could be developed for
the specific food components in question and that amounts detected
through those methods could be added to the dietary fiber value
determined by using the standard AOAC method for dietary fiber -- in
other words, an additive approach.[^75] As FDA has recognized, more
analytical development may be needed to resolve issues raised by an
additive approach. Nevertheless, this appears to be a manageable task.
ILSI Europe has suggested:

> If there is agreement that a) dietary fibre is the sum of non-starch
> polysaccharides, resistant starch and non-digestible oligosaccharides
> and that b) three (or possibly more) methods are required for complete
> analysis of these components, then it is important to ensure that
> there is no overlap in quantification among these methods .... In
> order to validate labelling declarations and claims, it may be
> necessary to specify different methods for measurement of the dietary
> fibre content in different foods.[^76]

This work cannot begin until a definition has been agreed to, but with
the definition in hand, the analytical development work likely could
progress fairly rapidly.

FDA has already set the stage for this approach through its 1993
rulemaking, which required analysis by specified AOAC methods "or, if no
AOAC method is available or appropriate, by other reliable and
appropriate analytical procedures."[^77] This provision recognizes that
there may be a need for development of new analytical methods to address
new situations. FDA has already engaged in work to help develop such
methods.[^78] Now the question before FDA is what the analytical methods
should accurately measure.

The FAO/WHO expert group has advocated that limiting the definition to
plant-made materials only would support reliance on the Englyst (also
called the NSP (Non-Starch Polysaccharides)) analytical methods.[^79]
The Englyst methods have been criticized as having possibly low
reproducibility.[^80] The Codex Committee on Nutrition and Foods for
Special Dietary Uses ("CCNFSDU") has explained:

> The Englyst method, which is not used world-wide, is complicated and
> may therefore be less suitable for routine analysis \[than AOAC
> methods\].

The Agence Française de Securité Sanitaire des Aliments ("AFSSA") agrees
with this assessment and adds:

> The **NSP** (Non-Starch Polysaccharides) method (Englyst *et al.*
> 1994) measures only the polysaccharides precipitated by 80% ethanol
> (approximately PD≥ 12), following total elimination of starch ....
>
> The highest fibre content is obtained with the AOAC method, the lowest
> with the NSP method ....
>
> The NSP method requires a lot of equipment (CPG or HPLC) and is not
> very compatible with routine analysis. It is, however, more
> satisfactory for research purposes.[^81]

In contrast, the CCNFSDU has said of AOAC methods for dietary fiber:

> These methods have the advantage of being used world-wide as well as
> being easily used in routine analysis.[^82]

Similarly, the AFSSA declares:

> The AOAC method of analyzing dietary fibre is by far the most commonly
> used in the world.[^83]

Thus, in addition to differences in ease of use, adoption of the Englyst
method by FDA would further narrow what is considered dietary fiber at a
time when Americans need to consume more dietary fiber, with the result
that fewer food materials would be considered to be dietary fiber than
under even the current FDA approach.

The Englyst methods are mainly for analysis of plant-made materials
only. If, as Dow recommends, FDA adopts a definition of "dietary fiber"
which is not limited to plant-made materials, it will have no reason to
adopt the Englyst methods.

[]{#__RefHeading___Toc197220678 .anchor}**[CONCLUSION]{.underline}**

FDA should adopt a definition of "dietary fiber" based on the
physiological effects commonly associated with dietary fiber. Such a
definition would:

-   Free FDA from having outdated restrictions on allowable analytical
    methods.

-   Avoid the need to spend FDA resources updating its restrictions on
    allowable analytical methods.

-   Be in accordance with the global trend in addressing dietary fiber
    on the basis of physiological effects.

-   Provide consumers with more, rather than less, information that can
    permit healthy food choices, particularly with respect to processed
    foods.

-   Be flexible enough to encompass new scientific findings about the
    physiological effects of dietary fiber.

-   Help assure consumer protection.

**[APPENDIX]{.underline}**

**[Recent Proposed or Official Definitions of "Dietary
Fiber"]{.underline}**

**1. [The IOM Definition]{.underline}**

In 2001, the Food and Nutrition Board of the Institute of Medicine
proposed the following definitions:

1.  *Dietary Fiber* consists of nondigestible carbohydrates and lignin
    that are intrinsic and intact in plants.

2.  *Added Fiber* consists of isolated, nondigestible carbohydrates that
    have beneficial physiological effects in humans.

> *Total Fiber* is the total of *Dietary Fiber* and *Added Fiber*.[^84]

In 2002, IOM renamed "added fiber" as "functional fiber".[^85]

These proposed definitions would limit dietary fiber to plant-based
materials such as cellulose, thereby excluding processed materials such
as modified celluloses. Physiological effects would only have to be
established for added fiber. The definition does not identify specific
physiological effects.

**2. [The AACC Definition]{.underline}**

Also in 2001, the American Association of Cereal Chemists (now AACC
International) presented its definition:

> Dietary fiber is the edible parts of plants or analogous carbohydrates
> that are resistant to digestion and absorption in the human small
> intestine with complete or partial fermentation in the large
> intestine. Dietary fiber includes polysaccharides, oligosaccharides,
> lignin, and associated plant substances. Dietary fibers promote
> beneficial physiological effects including laxation, and/or blood
> cholesterol attenuation, and/or blood glucose attenuation.[^86]

This definition is not limited to plant-based materials. It identifies
specific physiological effects.

**3. [The Codex Proposed Definition]{.underline}**

In 2005, the Codex Alimentarius Commission Committee on Nutrition and
Foods for Special Dietary Uses proposed the following:[^87]

> **Definition and properties of dietary fibre:**
>
> **Definition:**
>
> Dietary fibre means carbohydrate polymers[^88] with a degree of
> polymerization (DP) not lower than 3, which are neither digested nor
> absorbed in the small intestine. A degree of polymerization not lower
> than 3 is intended to excluded mono- and disaccharides. It is not
> intended to reflect the average DP of a mixture. Dietary fibre
> consists of one or more of:

-   Edible carbohydrate polymers naturally occurring in the food as
    consumed,

-   Carbohydrate polymers, which have been obtained from food raw
    material by physical, enzymatic or chemical means,

-   Synthetic carbohydrate polymers.

> **Properties:**
>
> Dietary fibre generally has properties such as:

-   Decrease intestinal transit time and increase stools bulk

-   Fermentable by colonic microflora

-   Reduce blood total and/or LDL cholesterol levels

-   Reduce post-prandial blood glucose and/or insulin levels.

> With the exception of non-digestible edible carbohydrate polymers
> naturally occurring in foods as consumed where a declaration or claim
> is made with respect to dietary fibre, a physiological effect should
> be scientifically demonstrated by clinical studies and other studies
> as appropriate. The establishment of criteria to quantify
> physiological effects is left to national authorities.

This definition is based on physiological effects and includes synthetic
materials. It is currently under review.[^89]

**4. [The FAO/WHO Expert Working Group Proposed
Definition]{.underline}**

In 2006, an expert working group within FAO/WHO proposed a very
different definition of "dietary fibre":

> Dietary fibre consists of intrinsic plant cell wall
> polysaccharides.[^90]

This proposed definition is based on chemical structure, not
physiological effects, and excludes synthetic materials. This proposed
definition has attracted many adverse comments.[^91]

**5. [The European Food Safety Authority Proposed
Definition]{.underline}**

While the EU has not adopted a formal definition of "dietary fiber", in
2007 the European Food Safety Authority's Scientific Panel on Dietetic
Products, Nutrition and Allergies proposed the following:

> Therefore, for the purposes of this statement, dietary fibre is
> defined as non-digestible carbohydrates plus lignin. The Panel
> considers that the main types of total dietary fibre are:

-   Non-starch polysaccharides -- cellulose, hemicelluloses, pectins,
    hydrocolloids (i.e., gums, mucilages, β-glucans).

-   Resistant oligosaccharides -- fructo-oligosaccharides (FOS),
    galacto-oligosaccharides (GOS), other resistant oligosaccharides.

-   Resistant starch -- consisting of physically enclosed starch, some
    types of raw starch granules, retrograded amylose, chemically and/or
    physically modified starches.

-   Lignin naturally associated with the dietary fibre polysaccharides.

The recommendation notes that this definition is similar to the Codex
proposed definition.[^92]

**6. [The Health Council of the Netherlands Proposed
Definition]{.underline}**

In 2006, the Health Council of the Netherlands Committee on Dietary
Fibre proposed this definition:

> The Committee uses the term 'dietary fibre' in this advisory report on
> account
>
> of its recognisability and international use. It defines dietary fibre
> as 'carbohydrates, compounds analogous to carbohydrates, and lignin
> and related substances that are not digested or absorbed in the human
> small intestine'. The substances that conform to the definition of
> dietary fibre are extremely diverse in character. By way of
> illustration, a number of substances that satisfy the definition are
> listed in Table 1.[^93]

Table 1 has the following groups: polysaccharides other than starch, and
indigestible oligosaccharides; compounds analogous to carbohydrates;
lignin; and substances that occur in products containing lignin or
polysaccharides other than starch. Methylcellulose and HPMC are among
the compounds analogous to carbohydrates that are listed.

**7. [The Agence Française]{.underline}** **[de Securité Sanitaire des
Aliments Proposed Definition]{.underline}**

In 2002, the Agence Française de Securité Sanitaire des Aliments
Specialist Expert Committee on Human Nutrition issued its proposed
definition:

> Dietary fibre consists of:

-   Carbohydrate polymers (Polymerization Degree (PD)
    [\>]{.underline} 3) of plant origin, which may or may not be
    associated in the plant with lignin or other non-carbohydrate
    components (polyphenols, waxes, saponins, cutin, phytates,
    phytosterols, etc.).

> [OR]{.underline}

-   Carbohydrate polymers (PD [\>]{.underline} 3), processed (by
    physical, enzymatic or chemical means) or synthetic, included in the
    attached list whose contents may change on the basis of AFSSA
    recommendations.

> [IN ADDITION]{.underline} dietary fibre is neither digested nor
> absorbed in the small intestine. It has at least one of the following
> properties:

-   Increase stools production

-   Stimulate colonic fermentation

-   Reduce pre-prandial cholesterol levels

-   Reduce post-prandial blood sugar and/or insulin levels[^94]

The list referred to in the definition did not specifically identify
either methylcellulose or HPMC, but the report mentioned that the
polymers suggested for inclusion on the positive list include
"Chemically modified fibre of plant origin (including cellulose and
modified starch currently permitted as ingredients or additives)"; that
description includes methylcellulose and HPMC.

**8. [The Food Standards Australia New Zealand Definition]{.underline}**

In 2001, the Food Standards Australia New Zealand (an independent
statutory agency in the two countries) adopted the following definition:

::: Definition
**dietary fibre** means that fraction of the edible part of plants or
their extracts, or synthetic analogues that --
:::

\(a\) are resistant to the digestion and absorption in the small
intestine, usually with complete or partial fermentation in the large
intestine; and

\(b\) promote one or more of the following beneficial physiological
effects --

\(i\) laxation;

\(ii\) reduction in blood cholesterol;

\(iii\) modulation of blood glucose;

::: Definition
> and includes polysaccharides, oligosaccharides (degree of
> polymerisation \> 2) and lignins.[^95]
:::

This definition explicitly includes synthetic analogues of plant-made
materials.

[^1]: With annual sales of \$54 billion and 46,000 employees worldwide,
    Dow is a diversified chemical company that combines the power of
    science and technology with the \"Human Element" to constantly
    improve what is essential to human progress. The Company delivers a
    broad range of products and services to customers in around 160
    countries, connecting chemistry and innovation with the principles
    of sustainability to help provide everything from fresh water, food
    and pharmaceuticals to paints, packaging and personal care products.
    References to "Dow" or the "Company" mean The Dow Chemical Company
    and its consolidated subsidiaries unless otherwise expressly noted.
    More information about Dow can be found at
    [www.dow.com](../../../../../../../../C:%5CDocuments%20and%20Settings%5Cu645589%5CDesktop%5Cwww.dow.com).

[^2]: 72 Fed. Reg. 62149 (Nov. 2, 2007). The deadline for submitting
    comments was extended to April 30, 2008. 73 Fed. Reg. 4765 (Jan. 28,
    2008).

[^3]: Methylcellulose is generally recognized as safe ("GRAS") under a
    wide variety of conditions of use, as is HPMC. See 21 CFR § 182.1490
    (methylcellulose); GRAS Notice No. GRN 00213 (FDA response letter
    Mar. 27, 2007), available at
    <http://www.cfsan.fda.gov/~rdb/opa-g213.html> (HPMC).

[^4]: Food and Nutrition Board, Institute of Medicine, "Dietary
    Reference Intakes Proposed Definition of Dietary Fiber: A Report of
    the Panel on the Definition of Dietary Fiber and the Standing
    Committee on the Scientific Evaluation of Dietary Reference Intakes,
    Food and Nutrition Board, Institute of Medicine" (2001), available
    at <http://www.nap.edu/catalog.php?record_id=10161>.

[^5]: 52 Fed. Reg. 28690 (Aug. 3, 1987), revising 21 CFR § 101.9(c)(3).

[^6]: Pub. L. 101-535, § 2(a), adding Section 403(q) to the Federal
    Food, Drug, and Cosmetic Act ("FFDCA").

[^7]: 21 CFR § 101.9(c)(6)(i).

[^8]: Thus, the ANPR is in error in stating without qualification that
    "Because there is not a formal definition of dietary fiber \[in FDA
    regulations\], dietary fiber is the material isolated using AOAC
    INTERNATIONAL Enzymatic-Gravimetric Method 985.29 (Ref. 12)." 72
    Fed. Reg. 62149, 62166 (Nov. 2, 2007).

[^9]: 21 CFR § 101.9(g)(2).

[^10]: 58 Fed. Reg. 2079, 2112 (Jan. 6, 1993).

[^11]: [Id]{.underline}\...

[^12]: See
    [www.aoac.org/oma/oma_18th_rev2.pdf](http://www.aoac.org/oma/oma_18th_rev2.pdf),

[^13]: This history is discussed in detail in Prosky, L., "What is
    fibre? Current controversies", Trends in Food Science & Technology
    10:271-275 (1999).

[^14]: 21 CFR § 101.81(c)(2)(ii)((B)(*2*) (determination of the amount
    of soluble fiber in psyllium husk for purposes of making a health
    claim).

[^15]: Dow studies using official AOAC enzymatic-gravimetric methods
    found recoveries of different grades of methylcellulose and HPMC
    ranging from 101% down to 5%, with most values less than 50%.

[^16]: American Association of Cereal Chemists, "The Definition of
    Dietary Fiber, Report of the Dietary Fiber Definition Committee to
    the Board of Directors of the American Association of Cereal
    Chemists", Cereal Foods World 46:112-126 (2001), available at
    [www.aaccnet.org/news/pdfs/DFDef.pdf](http://www.aaccnet.org/news/pdfs/DFDef.pdf).

[^17]: Food and Nutrition Board, Institute of Medicine, "Dietary
    Reference Intakes Proposed Definition of Dietary Fiber: A Report of
    the Panel on the Definition of Dietary Fiber and the Standing
    Committee on the Scientific Evaluation of Dietary Reference Intakes,
    Food and Nutrition Board, Institute of Medicine" (2001), available
    at <http://www.nap.edu/catalog.php?record_id=10161>.

[^18]: Turowski, M., et al., "A method for determination of soluble
    dietary fiber in methylcellulose and hydroxypropyl methylcellulose
    food gums", J. Food Comp. Anal. 20:420-429 (Aug. 2007); Harfmann,
    R., et al., "Determination of Methylcellulose and Hydroxypropyl
    Methylcellulose Food Gums in Food and Food Products: Collaborative
    Study", J. AOAC Int'l, 90:786-793 (2007); Deshmuth, B., et al.,
    "Validation of a size exclusion liquid chromatographic method for
    determination of methylcellulose and hydroxypropyl methylcellulose
    food gums as soluble dietary fiber in food and food product", Food
    Chem. 104:852-857 (2007).

[^19]: See AOAC, "OAM 18^th^ Ed. (Current Through Revision 2, 2007)",
    available at
    [www.aoac.org/oma/oma_18th_rev2.pdf](http://www.aoac.org/oma/oma_18th_rev2.pdf).
    Method 2006.08 is classified there as Section 32.1.42, covering
    "Cereal Foods", and within that category, "Wheat Flour".

[^20]: Gordon, D., "Dietary Fiber Definitions at Risk", Cereal Foods
    World 52:112-123 (2007), available at
    <http://www.aaccnet.org/cerealfoodsworld/tablescontents2007.asp>;
    Dietary Fibre Workshop (2006), available at
    <http://www.svs.fi/DFW06/>.

[^21]: 21 CFR § 101.9(g)(2).

[^22]: 55 Fed. Reg. 29487 (July 19, 1990).

[^23]: Food and Nutrition Board, Institute of Medicine, "Dietary
    Reference Intakes Proposed Definition of Dietary Fiber: A Report of
    the Panel on the Definition of Dietary Fiber and the Standing
    Committee on the Scientific Evaluation of Dietary Reference Intakes,
    Food and Nutrition Board, Institute of Medicine" (2001), available
    at <http://www.nap.edu/catalog.php?record_id=10161>.

[^24]: Ku, Y. et al., "An approach to modifying AOAC total dietary fiber
    Method 985.29 to better fit a physiologic definition of dietary
    fiber", abstract, 2001 AACC Annual Meeting, Charlotte, NC (Oct.
    14-18, 2001), available at
    <http://www.aaccnet.org/meetings/2001/Abstracts/a01ma363.htm>
    (emphasis added).

[^25]: Englyst, K., et al., "Nutritional characterization and
    measurement of dietary carbohydrates", European J. of Clinical
    Nutrition, 61 (Suppl 1), S19-S39 (2007).

[^26]: 21 CFR § 101.9(c)(6)(iv).

[^27]: Food and Nutrition Board, Institute of Medicine, "Dietary
    Reference Intakes Proposed Definition of Dietary Fiber: A Report of
    the Panel on the Definition of Dietary Fiber and the Standing
    Committee on the Scientific Evaluation of Dietary Reference Intakes,
    Food and Nutrition Board, Institute of Medicine" (2001), available
    at <http://www.nap.edu/catalog.php?record_id=10161>.

[^28]: Food and Nutrition Board, Institute of Medicine, "Dietary,
    functional, and total fiber", in [Dietary Reference Intakes: Energy,
    Carbohydrates, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and
    Amino Acids (Macronutrients)]{.underline} (2002), available at
    <http://www.nap.edu/catalog.php?record_id=10490>.

[^29]: See, e.g., FDA, "Bulking Up Fiber's Healthful Reputation", FDA
    Consumer (July-Aug. 1997, rev. 1998), available at
    <http://www.cfsan.fda.gov/~dms/fdafiber.html>, where FDA itself
    attributed the benefits of "fiber" exclusively to "dietary fiber"
    and made no reference to "other carbohydrates".

[^30]: British Nutrition Association, "Response to the proposed
    definition of fibre" (June 2007), available at
    [www.nutrition.org.uk/home.asp?siteId=43&sectionId=1495&subSectionId=1479&parentSection=304](http://www.nutrition.org.uk/home.asp?siteId=43&sectionId=1495&subSectionId=1479&parentSection=304)\....

[^31]: International Life Sciences Institute Europe, "Dietary Fibre:
    Definition, Analysis, Physiology & Health" at 5, IILSI Europe
    Concise Monograph Series (2006), available at
    <http://europe.ilsi.org/NR/rdonlyres/0603B318-9329-4F54-9029-F7D27AEF3272/0/DietaryFibre.pdf>.

[^32]: Englyst, K., et al., "Nutritional characterization and
    measurement of dietary carbohydrates", Eur. J. of Clin. Nutr., 61
    (Suppl 1), S19-S39 (2007).

[^33]: American Association of Cereal Chemists, "The Definition of
    Dietary Fiber, Report of the Dietary Fiber Definition Committee to
    the Board of Directors of the American Association of Cereal
    Chemists", Cereal Foods World 46:112-126 (2001), available at
    [www.aaccnet.org/news/pdfs/DFDef.pdf](http://www.aaccnet.org/news/pdfs/DFDef.pdf).

[^34]: H.R. Rep. No. 101-538, at 14 (1990), *as reprinted in* 1990
    U.S.C.C.A.N. 3336, 3343-44 (emphasis added).

[^35]: Food and Nutrition Board, Institute of Medicine, "Dietary
    Reference Intakes Proposed Definition of Dietary Fiber: A Report of
    the Panel on the Definition of Dietary Fiber and the Standing
    Committee on the Scientific Evaluation of Dietary Reference Intakes,
    Food and Nutrition Board, Institute of Medicine" (2001), available
    at <http://www.nap.edu/catalog.php?record_id=10161>.

[^36]: Id.

[^37]: This definition appeared in CRD 19, which is not itself available
    on the Codex Alimentarius Commission ("Codex") website. The text
    appears as an appendix in Codex Committee on Nutrition and Foods for
    Special Dietary Uses Circular Letter, "Guidelines for the Use of
    Nutrition Claims: Draft Table of Conditions for Nutrient Contents
    (Part B Containing Provisions on Dietary Fibre) at Step 6", CL
    2007/3-NFSDU (Jan. 2007), available at
    <http://www.codexalimentarius.net/web/circular.jsphttp://www.codexalimentarius.net/web/circular.jsp>.

[^38]: Codex Committee on Nutrition and Foods for Special Dietary Uses,
    29^th^ Session, "Guidelines for the Use of Nutrition Claims: Draft
    Table of Conditions for Nutrient Contents (Part B Containing
    Provision on Dietary Fibre) -- Comments at Step 6 of Procedure",
    CX/NFSDU 07/29/3 (Nov. 2007), available at
    <ftp://ftp.fao.org/codex/ccnfsdu29/nf29_03e.pdf>.

[^39]: Comments of Japan in Codex Committee on Nutrition and Foods for
    Special Dietary Uses, 29^th^ Session, "Guidelines for the Use of
    Nutrition Claims: Draft Table of Conditions for Nutrient Contents
    (Part B Containing Provision on Dietary Fibre) -- Comments at Step 6
    of Procedure", CX/NFSDU 07/29/3 (Nov. 2007), available at
    <ftp://ftp.fao.org/codex/ccnfsdu29/nf29_03e.pdf>.

[^40]: Comments of Institute of Food Technologies in Codex Committee on
    Nutrition and Foods for Special Dietary Uses, 29^th^ Session,
    "Guidelines for the Use of Nutrition Claims: Draft Table of
    Conditions for Nutrient Contents (Part B Containing Provision on
    Dietary Fibre) -- Comments at Step 6 of Procedure", CX/NFSDU 07/29/3
    (Nov. 2007), available at
    <ftp://ftp.fao.org/codex/ccnfsdu29/nf29_03e.pdf>.

[^41]: Food and Nutrition Board, Institute of Medicine, "Dietary,
    functional, and total fiber", in [Dietary Reference Intakes: Energy,
    Carbohydrates, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and
    Amino Acids (Macronutrients)]{.underline}, (2002/2005), at 339,
    available at <http://www.nap.edu/catalog.php?record_id=10490>.

[^42]: Comments of International Council of Grocery Manufacturer
    Associations in Codex Committee on Nutrition and Foods for Special
    Dietary Uses, 29^th^ Session, "Guidelines for the Use of Nutrition
    Claims: Draft Table of Conditions for Nutrient Contents (Part B
    Containing Provision on Dietary Fibre) -- Comments at Step 6 of
    Procedure", CX/NFSDU 07/29/3 (Nov. 2007), available at
    <ftp://ftp.fao.org/codex/ccnfsdu29/nf29_03e.pdf>

[^43]: See, e.g., Gordon, D., "Dietary Fiber Definitions at Risk",
    Cereal Foods World 52:112-123 (2007), available at
    <http://www.aaccnet.org/cerealfoodsworld/tablescontents2007.asp>.

[^44]: International Life Sciences Institute Europe, "Dietary Fibre:
    Definition, Analysis, Physiology & Health" at 5, ILSI Europe Concise
    Monograph Series (2006), available at
    <http://europe.ilsi.org/NR/rdonlyres/0603B318-9329-4F54-9029-F7D27AEF3272/0/DietaryFibre.pdf>.

[^45]: European Food Safety Authority, "Statement of the Panel on
    Dietetic Products, Nutrition and Allergies on a request from the
    Commission related to dietary fibre (Request N° DFSA-Q-2007-121)"
    (2007), available at
    <http://www.efsa.eu.int/EFSA/efsa_locale-1178620753812_1178630797984.htm>.

[^46]: American Association of Cereal Chemists, "All Dietary Fiber Is
    Fundamentally Functional", Report of by the AACC Dietary Fiber
    Technical Committee, Cereal Foods World 48:128-131 (2003) (citation
    omitted), available at
    [www.aaccnet.org/news/pdfs/DFreport.pdf](http://www.aaccnet.org/news/pdfs/DFreport.pdf).

[^47]: Comments of Japan in Codex Committee on Nutrition and Foods for
    Special Dietary Uses, 29^th^ Session, "Guidelines for the Use of
    Nutrition Claims: Draft Table of Conditions for Nutrient Contents
    (Part B Containing Provision on Dietary Fibre) -- Comments at Step 6
    of Procedure", CX/NFSDU 07/29/3 (Nov. 2007), available at
    <ftp://ftp.fao.org/codex/ccnfsdu29/nf29_03e.pdf>.

[^48]: International Life Sciences Institute Europe, "Dietary Fibre:
    Definition, Analysis, Physiology & Health" at 5, ILSI Europe Concise
    Monograph Series (2006), available at
    <http://europe.ilsi.org/NR/rdonlyres/0603B318-9329-4F54-9029-F7D27AEF3272/0/DietaryFibre.pdf>.

[^49]: American Association of Cereal Chemists, "The Definition of
    Dietary Fiber, Report of the Dietary Fiber Definition Committee to
    the Board of Directors of the American Association of Cereal
    Chemists", Cereal Foods World 46:112-126 (2001), available at
    [www.aaccnet.org/news/pdfs/DFDef.pdf](http://www.aaccnet.org/news/pdfs/DFDef.pdf).

[^50]: See American Association of Cereal Chemists, "All Dietary Fiber
    Is Fundamentally Functional", Report by the AACC Dietary Fiber
    Technical Committee, Cereal Foods World 48:128-131 (2003), available
    at
    [www.aaccnet.org/news/pdfs/DFreport.pdf](http://www.aaccnet.org/news/pdfs/DFreport.pdf).

[^51]: International Life Sciences Institute Europe, "Dietary Fibre:
    Definition, Analysis, Physiology & Health" at 5, ILSI Europe Concise
    Monograph Series (2006), available at
    <http://europe.ilsi.org/NR/rdonlyres/0603B318-9329-4F54-9029-F7D27AEF3272/0/DietaryFibre.pdf>.

[^52]: European Food Safety Authority, "Statement of the Panel on
    Dietetic Products, Nutrition and Allergies on a request from the
    Commission related to dietary fibre (Request N° DFSA-Q-2007-121)"
    (2007), available at
    <http://www.efsa.eu.int/EFSA/efsa_locale-1178620753812_1178630797984.htm>.

[^53]: International Life Sciences Institute Europe, "Dietary Fibre:
    Definition, Analysis, Physiology & Health" at 5, ILSI Europe Concise
    Monograph Series (2006), available at
    <http://europe.ilsi.org/NR/rdonlyres/0603B318-9329-4F54-9029-F7D27AEF3272/0/DietaryFibre.pdf>

[^54]: American Association of Cereal Chemists, "The Definition of
    Dietary Fiber", Report of the Dietary Fiber Definition Committee to
    the Board of Directors of the American Association of Cereal
    Chemists, Cereal Foods World 46:112-126 (2001), available at
    [www.aaccnet.org/news/pdfs/DFDef.pdf](http://www.aaccnet.org/news/pdfs/DFDef.pdf).

[^55]: Codex Committee on Nutrition and Foods for Special Dietary Uses,
    "Report of the 27^th^ Session of the Codex Committee on Nutrition
    and Foods for Special Dietary Uses", ALINORM 06/29/26 (2006),
    available at
    [www.ccnfsdu.de/fileadmin/user_upload/PDF/ReportCCNFSDU2005.pdf](http://www.ccnfsdu.de/fileadmin/user_upload/PDF/ReportCCNFSDU2005.pdf).

[^56]: Agence Française de Securité Sanitaire des Aliments, "Dietary
    fibre: definitions, analysis and nutrition claims -- Report of the
    Specialist Expert Committee on Human Nutrition" (2002), available in
    French and English at
    <http://www.bdsp.tm.fr/FullText/Show.asp?Ref=332233>.

[^57]: Health Council of the Netherlands, "Guideline for dietary fibre
    intake", No. 2006/03E (2006), available in English at
    <http://europa.eu/sinapse/sinapse/index.cfm?fuseaction=lib.attachment&lib_id=1A2E0904-C09F-3EDB-B3FEF1B1D95D5>\.....

[^58]: British Nutrition Association, "Response to the proposed
    definition of fibre" (June 2007), available at
    [www.nutrition.org.uk/home.asp?siteId=43&sectionId=1495&subSectionId=1479&parentSection=304](http://www.nutrition.org.uk/home.asp?siteId=43&sectionId=1495&subSectionId=1479&parentSection=304)\....

[^59]: Agence Française de Securité Sanitaire des Aliments, "Dietary
    fibre: definitions, analysis and nutrition claims -- Report of the
    Specialist Expert Committee on Human Nutrition" (2002), available in
    French and English at
    <http://www.bdsp.tm.fr/FullText/Show.asp?Ref=332233>.

[^60]: The following refer to methylcellulose, which is closely related
    to HPMC: Yokoyama, W., et al., "Stability of ingested
    methylcellulose in the rat determined by polymer molar mass
    measurements by light scattering", J. Agric. Food Chem. 50:7726-7730
    (2002); Braun, W., et al., "The lack of significant absorption of
    methylcellulose, viscosity 3300 cp, from the intestinal tract
    following single and multiple oral doses in the rat", Food Cosmet.
    Toxicol. 12:373-376 (1974); Machle, W., "The fate of methylcellulose
    in the human digestive tract", J. Biol. Chem. 153:551-559 (1944).

[^61]: Reppas, C., et al., "Hydroxypropylmethylcellulose significantly
    lowers blood cholesterol in mildly hypercholesterolemic human
    subjects", Eur. J. Clin. Nutr., advance online publication 19 Sept.
    2007; doi:10.1038/sj.ejcn.1602903; Maki, K., "High-Molecular-Weight
    Hydroxypropylmethylcellulose Taken with or between Meals Is
    Hypocholesterolemic in Adult Men", J. Nutr. 130:1705-1710 (2000);
    Maki, K., "Cholesterol Lowering With High Viscosity
    Hydroxypropylmethylcellulose", Am. J. Cardiol. 84:1198-1203 (1999);
    Swidan, S., "Ability of two comestible formulations of
    hydroxypropylmethylcellulose to lower serum cholesterol
    concentrations", Eur. J. Pharm. Sci. 4:239-245 (1996); Dressman, J.,
    et al., "High-Molecular-Weight Hydroxypropylmethylcellulose -- A
    Cholesterol-Lowering Agent", Arch. Int. Med. 153:1345-1353 (1993).

[^62]: Maki, K., et al., "Hydroxypropylmethylcellulose and
    Methylcellulose Consumption Reduce Postprandial Insulinemia in
    Overweight and Obese Men and Women", J. Nutr. 138:292-296 (2008);
    Maki, K, et al., "High Viscosity Hydroxypropylmethylcellulose Blunts
    Postprandial Glucose and Insulin Responses", Diabetes Care
    30:1039-1043 (2007); Reppas, C., et al., "High viscosity
    hydroxypropylmethylcellulose reduces postprandial blood glucose
    concentrations in NIDDM patients", Diabetes Res. Clin. Pract.
    22:61-69 (1993).

[^63]: Reppas, C., et al., "Hydroxypropylmethylcellulose significantly
    lowers blood cholesterol in mildly hypercholesterolemic human
    subjects", Eur. J. Clin. Nutr., advance online publication 19 Sept.
    2007; doi:10.1038/sj.ejcn.1602903; Swidan, S., "Ability of two
    comestible formulations of hydroxypropylmethylcellulose to lower
    serum cholesterol concentrations", Eur. J. Pharm. Sci. 4:239-245
    (1996); Dressman, J., et al., "High-Molecular-Weight
    Hydroxypropylmethylcellulose -- A Cholesterol-Lowering Agent", Arch.
    Int. Med. 153:1345-1353 (1993).

[^64]: Wyatt, G., et al., "Intestinal microflora and gastrointestinal
    adaptation in the rat in response to non-digestible dietary
    polysaccharides", Brit. J. Nutr. 60:197-207 (1988).

[^65]: See, e.g., Health Council of the Netherlands, "Guideline for
    dietary fibre intake", No. 2006/03E (Mar. 2006), available in
    English at
    <http://europa.eu/sinapse/sinapse/index.cfm?fuseaction=lib.attachment&lib_id=1A2E0904-C09F-3EDB-B3FEF1B1D95D5>\.....

[^66]: Comments of the United States in Codex Committee on Nutrition and
    Foods for Special Dietary Uses, "Report of the 29^th^ Session of the
    Codex Committee on Nutrition and Foods for Special Dietary Use",
    ALINORM 08/31/26 (Nov. 2007), available at
    <http://www.codexalimentarius.net/web/archives.jsp?lang=en>.

[^67]: H.R. Rep. No. 101-538, at 19 (1990), *as reprinted in* 1990
    U.S.C.C.A.N. 3336, 3349.

[^68]: 21 CFR § 101.93.

[^69]: 21 CFR Part 101, Subpart E.

[^70]: 21 CFR § 101.71(a).

[^71]: E.g., 21 CFR § 101.81.

[^72]: Rader, J., and Ku, Y., "FDA's perspective on recent
    recommendations for definitions of dietary fiber: potential
    consequences for health claims and analysis", abstract, 2001 AACC
    Annual Meeting, Charlotte, NC (Oct. 14-18, 2001), available at
    <http://www.aaccnet.org/meetings/2001/Abstracts/a01ma127.htm>.

[^73]:
    #  FDA, "Substantiation for Dietary Supplement Claims Made Under Section 403(r) (6) of the Federal Food, Drug, and Cosmetic Act" (Draft guidance 2004), available at [**http://www.cfsan.fda.gov/\~dms/dsclmgui.html**](http://www.cfsan.fda.gov/~dms/dsclmgui.html). 

[^74]: Comments of the United States in Codex Committee on Nutrition and
    Foods for Special Dietary Uses, 29^th^ Session, "Guidelines for the
    Use of Nutrition Claims: Draft Table of Conditions for Nutrient
    Contents (Part B Containing Provision on Dietary Fibre) -- Comments
    at Step 6 of Procedure", CX/NFSDU 07/29/3 (Nov. 2007), available at
    <ftp://ftp.fao.org/codex/ccnfsdu29/nf29_03e.pdf>

[^75]: See Prosky, L., "What is fibre? Current controversies", Trends in
    Food Science & Technology 10:271-275 (1999).

[^76]: International Life Sciences Institute Europe, "Dietary Fibre:
    Definition, Analysis, Physiology & Health" at 6, ILSI Europe Concise
    Monograph Series (2006), available at
    <http://europe.ilsi.org/NR/rdonlyres/0603B318-9329-4F54-9029-F7D27AEF3272/0/DietaryFibre.pdf>.

[^77]: 21 CFR § 101.9(g)(2).

[^78]: See, e.g., Ku, Y. et al., "An approach to modifying AOAC total
    dietary fiber Method 985.29 to better fit a physiologic definition
    of dietary fiber", abstract, 2001 AACC Annual Meeting, Charlotte, NC
    (Oct. 14-18, 2001), available at
    <http://www.aaccnet.org/meetings/2001/Abstracts/a01ma363.htm>.

[^79]: See Appendix II to CRD 19 as reproduced in Codex Circular Letter,
    "Guidelines for the Use of Nutrition Claims: Draft Table of
    Conditions for Nutrient Contents (Part B Containing Provisions on
    Dietary Fibre) at Step 6", CL 2007/3-NFSDU (Jan. 2007), available at
    <http://www.codexalimentarius.net/web/circular.jsphttp://www.codexalimentarius.net/web/circular.jsp>.

[^80]: International Life Sciences Institute Europe, "Dietary Fibre:
    Definition, Analysis, Physiology & Health" at 5, ILSI Europe Concise
    Monograph Series (2006), available at
    <http://europe.ilsi.org/NR/rdonlyres/0603B318-9329-4F54-9029-F7D27AEF3272/0/DietaryFibre.pdf>.

[^81]: Agence Française de Securité Sanitaire des Aliments, "Dietary
    fibre: definitions, analysis and nutrition claims -- Report of the
    Specialist Expert Committee on Human Nutrition" (2002), available in
    French and English at
    <http://www.bdsp.tm.fr/FullText/Show.asp?Ref=332233>.

[^82]: Codex Committee on Nutrition and Foods for Special Dietary Uses,
    "Report of the 27^th^ Session of the Codex Committee on Nutrition
    and Foods for Special Dietary Uses", ALINORM 06/29/26 (2006),
    Appendix III, available at
    [www.ccnfsdu.de/fileadmin/user_upload/PDF/ReportCCNFSDU2005.pdf](http://www.ccnfsdu.de/fileadmin/user_upload/PDF/ReportCCNFSDU2005.pdf),
    and reproduced in Codex Committee on Nutrition and Foods for Special
    Dietary Uses Circular Letter, "Guidelines for the Use of Nutrition
    Claims: Draft Table of Conditions for Nutrient Contents (Part B
    Containing Provisions on Dietary Fibre) at Step 6", CL 2007/3-NFSDU
    (Jan. 2007), available at
    <http://www.codexalimentarius.net/web/circular.jsphttp://www.codexalimentarius.net/web/circular.jsp>

[^83]: Agence Française de Securité Sanitaire des Aliments, "Dietary
    fibre: definitions, analysis and nutrition claims -- Report of the
    Specialist Expert Committee on Human Nutrition" (2002), available in
    French and English at
    <http://www.bdsp.tm.fr/FullText/Show.asp?Ref=332233>.

[^84]: Food and Nutrition Board, Institute of Medicine, "Dietary
    Reference Intakes Proposed Definition of Dietary Fiber: A Report of
    the Panel on the Definition of Dietary Fiber and the Standing
    Committee on the Scientific Evaluation of Dietary Reference Intakes,
    Food and Nutrition Board, Institute of Medicine" (2001), available
    at <http://www.nap.edu/catalog.php?record_id=10161>.

[^85]: Food and Nutrition Board, Institute of Medicine, "Dietary,
    functional, and total fiber", in [Dietary Reference Intakes: Energy,
    Carbohydrates, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and
    Amino Acids (Macronutrients)]{.underline} (2002/2005), at 339,
    available at <http://www.nap.edu/catalog.php?record_id=10490>.

[^86]: American Association of Cereal Chemists, "The Definition of
    Dietary Fiber, Report of the Dietary Fiber Definition Committee to
    the Board of Directors of the American Association of Cereal
    Chemists", Cereal Foods World 46:112-126 (2001), available at
    [www.aaccnet.org/news/pdfs/DFDef.pdf](http://www.aaccnet.org/news/pdfs/DFDef.pdf).

[^87]: Codex Committee on Nutrition and Foods for Special Dietary Uses,
    "Report of the 27^th^ Session of the Codex Committee on Nutrition
    and Foods for Special Dietary Uses", ALINORM 06/29/26 (2006),
    available at
    [www.ccnfsdu.de/fileadmin/user_upload/PDF/ReportCCNFSDU2005.pdf](http://www.ccnfsdu.de/fileadmin/user_upload/PDF/ReportCCNFSDU2005.pdf).

[^88]: The definition includes the following footnote: "When derived
    from a plant origin, dietary fibre may include fractions of lignin
    and/or other compounds when associated with polysaccharides in the
    plant cell walls and if these compounds are quantified by the AOAC
    gravimetric analytical method for dietary fibre analysis: Fractions
    of lignin and the other compounds (proteic fractions, phenolic
    compounds, waxes, saponins, pytates, cutin, phytosterols, etc.)
    intimately 'associated' with plant polysaccharides are often
    extracted with the polysaccharides in the AOAC 991.43 method. These
    substances are included in the definition of fibre insofar as they
    are actually associated with the poly- or oligo- saccharidic
    fraction of fibre. However, when extracted or even re-introduced
    into a food containing non digestible polysaccharides, they cannot
    be defined as dietary fibre. When combined with polysaccharides,
    these associated substances may provide additional benefits."

[^89]: Comments in the latest round of comments on this proposed
    definition were due 1 April 2008. See Codex Committee on Nutrition
    and Foods for Special Dietary Uses, "Report of the 29^th^ Session of
    the Codex Committee on Nutrition and Foods for Special Dietary Use",
    ALINORM 08/31/26 (Nov. 2007), available at
    <http://www.codexalimentarius.net/web/archives.jsp?lang=en>.

[^90]: This definition appeared in CRD 19, which is not itself available
    on the Codex website,
    <http://www.codexalimentarius.net/web/index_en.jsp>. Some details of
    its consideration appear in Codex Committee on Nutrition and Foods
    for Special Dietary Uses Circular Letter, "Report of the 28^th^
    Session of the Codex Committee on Nutrition and Foods for Special
    Dietary Uses", ALINORM 07/30/26-Rev. (Nov. 2006), available at
    <http://www.codexalimentarius.net/web/archives.jsp?year=07>. The
    text appears as an appendix in a Codex Committee on Nutrition and
    Foods for Special Dietary Uses Circular Letter, "Guidelines for the
    Use of Nutrition Claims: Draft Table of Conditions for Nutrient
    Contents (Part B Containing Provisions on Dietary Fibre) at Step 6",
    CL 2007/3-NFSDU (Jan. 2007), available at
    <http://www.codexalimentarius.net/web/circular.jsphttp://www.codexalimentarius.net/web/circular.jsp>.

[^91]: Comments on the proposed definition appear in Codex Committee on
    Nutrition and Foods for Special Dietary Uses Circular Letter,
    "Guidelines for the Use of Nutrition Claims: Draft Table of
    Conditions for Nutrient Contents (Part B Containing Provision on
    Dietary Fibre) -- Comments at Step 6 of the Procedure", CX/NFSDU
    07/29/3 (Nov. 2007), available at
    <ftp://ftp.fao.org/codex/ccnfsdu29/nf29_03e.pdf>.

[^92]: European Health Standards Authority, "Statement of the Panel on
    Dietetic Products, Nutrition and Allergies on a request from the
    Commission related to dietary fibre (Request N° DFSA-Q-2007-121)" (6
    July 2007), available at
    <http://www.efsa.eu.int/EFSA/efsa_locale-1178620753812_1178630797984.htm>.

[^93]: Health Council of the Netherlands, "Guideline for dietary fibre
    intake", No. 2006/03E (Mar. 2006), available in English at
    <http://europa.eu/sinapse/sinapse/index.cfm?fuseaction=lib.attachment&lib_id=1A2E0904-C09F-3EDB-B3FEF1B1D95D5>\.....

[^94]: Agence Française de Securité Sanitaire des Aliments, "Dietary
    fibre: definitions, analysis and nutrition claims -- Report of the
    Specialist Expert Committee on Human Nutrition" (2002), available in
    French and English at
    <http://www.bdsp.tm.fr/FullText/Show.asp?Ref=332233>.

[^95]: Food Standards Australia New Zealand, Food Standards Code,
    Standard 1.2.8, "Nutrition Information Requirements", available at
    <http://www.foodstandards.gov.au/thecode/foodstandardscode.cfm#_one>.