Glycative Stress Research
Online edition : ISSN 2188-3610
Print edition : ISSN 2188-3602
Received : December 15, 2020
Accepted : January 18, 2021
Published online : March 31, 2021
doi:10.24659/gsr.8.1_29

Original article

Effects on skin by dewaxed brown rice: An open label test.
Yoshikazu Yonei 1), Shiori Uenaka 1), Masayuki Yagi 1), Ursula Pasandee Pabasara Wickramasinghe 1),
Marin Kawakami 2), Ryo Yamaguchi 2), Naoki Nishiyama 2), Keiji Saika 2, 3), Mari Ogura 1, 4)1) Anti-Aging Medical Research Center and Glycative Stress Research Center, Faculty of Life and Medical Sciences,
Doshisha University, Kyoto, Japan
2) Toyo Rice Co., Ltd. ,Tokyo, Japan
3) Research Institute for Agricultural and Life Sciences, Tokyo University of Agriculture, Tokyo, Japan4) Kyoto Bunkyo Junior College, Kyoto, Japan

Abstract

Purpose: In this study, we compared the subjective symptoms and changes in skin condition of university students andstaffs with brown rice from which the bran layer had been removed (dewaxed brown rice: DBR) for one month, in comparison
with the polished rice free intake group.
Methods: The 65 subjects in the analysis group consisted of 43 in the DBR group (25 males and 18 females 23.8 ± 8.8
years) and 22 in the control group (13 males and 9 females 22.0 ± 1.2 years). In the DBR group, a test meal of 150 g or more
was ingested once a day for one month, and in the control group, polished rice was usually taken freely. Before and after the
test, the questionnaire, skin condition (Clreo-Pro), and skin AGE fluorescence (by AGEs sensor) were evaluated.
Results: DBR intake compliance was at 87.5 %, and no adverse events due to dyspepsia were observed. Skin age, an index ofskin condition, was significantly improved in the DBR group compared to the control. There was no significant difference inskin AGE fluorescence. Gender analysis showed that wrinkles and porphyrin levels were significantly improved in the DBR
group in women.
Conclusion: It was suggested that DBR could contribute to health promotion including skin condition by reducing theindigestibility of brown rice and ensuring nutritional value, which facilitates continuous intake.

KEY WORDS: brown rice, dewaxed brown rice (DBR), advanced glycation endproducts (AGEs),		Introduction

skin AGE fluorescence, skin condition

It has been pointed out that whole grains, i.e. brown
rice, may be effective in preventing lifestyle-related diseases
such as obesity, type 2 diabetes (T2DM), and coronary arterydisease 1, 2). The brown rice diet is rich in vitamins, minerals
and dietary fiber, and is clearly nutritionally superior topolished rice. However, there are some problems with
continuous intake of brown rice. Problems include the needfor long-term water immersion on the cooking side, the timerequired for digestion on the physical side, and the need forsufficient chewing.
Various measures have been attempted to reduce thedisadvantage of indigestibility while utilizing the nutritional
advantages of brown rice. Brown rice from which the wax
bran layer has been removed is called dewaxed brown rice(DBR) and there are reports of ingredients 3), improvementof constipation 4) and amerioration of fatty liver 5) in animal
experiments. In this study, we investigated changes insubjective symptoms, skin condition, and the accumulationof advanced glycation end products (AGEs), which is anindex of glycation stress, when the test product DBR wasingested for one month in young people, and compared witha group that ingested polished rice.

Contact Address: Professor Yoshikazu Yonei, MD, PhD
Anti-Aging Medical Research Center, Graduate School of Life and Medical Sciences,
Doshisha University
1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0394 Japan
TEL & FAX: + 81-774-65- 6394 e-mail: yyonei@mail.doshisha.ac.jp
Co-authors: Uenaka S, ctud2025@mail4.doshisha.ac.jp;
Yagi M, myagi@mail.doshisha.ac.jp; Wickramasinghe UPP, cygb2502@mail.doshisha.ac.jp;
Kawakami M, kawakami-marin@toyo-rice.jp; Yamaguchi R, r-yamaguchi@toyo-rice. jp;
Nishiyama N, nishiyama@toyo-rice.jp; Saika K, somu@toyo-rice.jp;
Ogura M, m-ogura@po.kbu.ac.jp_ 29 _

Glycative Stress Research 2021; 8 (1) : 29-38(c) Society for Glycative Stress ResearchEffects of Dewaxed Brown Rice

MethodSubjects

The subjects were male and female students and staffs
from a university in Tokyo ( including Yokohama campus).
This study was conducted with 66 subjects who agreed toparticipate in this trial in advance in writing, who met the
selection criteria, did not conflict with the exclusion criteria,
and were judged to be appropriate to participate by theprincipal investigator. The subjects enrolled in this study
were randomly designated by the assigners to the DBR groupand the control group.
The selection criteria are shown below.
1) Men and women 18 to 60 years old at the time when theconsent for participation in the study was obtained.
2) Persons in good health without chronic physical illness,
including skin diseases.
3) Persons with the ability to give consent after receiving anadequate explanation of the purpose and content of thestudy, and who volunteered to participate of their own
accord after proper understanding and providing a writtenconsent to participate in this study.
4) Persons who could attend the designated examination dateto undergo examination.
5) Persons determined to be suitable as a subject of this study
by the principal investigator.
The exclusion criteria are shown below.
1) Persons who are currently receiving medication due toillness2) Persons with a history of, or currently suffering from
impaired glucose tolerance, mental illness, sleep disorders,
hypertension, diabetes mellitus, dyslipidemia, or a serious
illness.
3) Persons who have been taking drugs for the treatmentof a disease for the past one month (excluding thosewith a history of taking temporary-relief medication forheadaches, menstrual pain, and colds)

4) Persons with a history of, or currently suffering from asevere disease of the liver, kidney, heart, lungs, digestiveorgans, or a hematologic disease.
5) Persons with a history of, or currently suffering froma severe disease of the gastrointestinal tract, excluding
appendicitis.
6) Persons with a body mass index (BMI) of more than 30
kg/m 2.
7) Those who may have allergic reactions to the test food,and those who may have serious allergic reactions to otherfoods or drugs.
8) Pregnant women, lactating women,or women who may
possibly be pregnant.
9) Currently, and within the past three months, those whohave a habit of continuously ingesting functional foods
and health foods that claim to be related to skin quality
improvement, and those who plan to take them during
the test period (ingestion for the purpose of maintaining
health was permitted).
10)Persons with photosensitivity.
11) Persons who have been determined by the principal
investigator as not suitable to be a subject of this study.

Figure 1 shows the transition of the number of test
subjects. The breakdown of 65 subjects analyzed was 43 in
the DBR group (25 men and 18 women) and 22 in the control
group (13 men and 9 women). The DBR group includes 7
university staffs (5 men and 2 women). The average age ofeach group was 23.8 ± 8.8 years in the DBR group (men24.2 ± 8.8 years, women 23.1 ± 9.1 years) and 22.0 ± 1.2
years in the control group (men 22.4 ± 1.2 years, women
21.4 ± 1. 0 years). The control group was the same as in theprevious report 6).

Exam design
This study was an open label study between parallelgroups.
The DBR group ingested brown rice from which the

Subjects who have obtained consent,
conducted a preliminary inspection, andwere incorporated into this studyn = 66
Drop -offn = 1 (subject convenience)
Intention-to-treatn = 65 (38 males, 27 females)n = 43 (25 males, 18 females)
DBR
Control: n = 22 (13 males, 9 females)
Fig. 1. Changes in the number of test subjects.

_ 30 _Glycative Stress Research

wax layer had been removed, and a control group was set inwhich normal polished rice without DBR was ingested freely.
The DBR group always ingested the test product once a day
during the test period by any of the following methods.
• DBR was cooked in the on-campus cafeteria, weighed,served at 150 g or more, and ingested.
• Packaged DBR (150 g) was heated in the microwave andingested.
The test product was provided by Toyo Rice Co., Ltd.
(Wakayama, Japan). The subjects participated in the preingestion test 1 day, the ingestion period 33 days, and thepost-intake test 1 day.
Pre-intake tests for each group included a backgroundsurvey via questionare on lifestyle and skin condition,skin condition measurement via device Clreo-Pro ( Fujitex,
Shinjuku-ku, Tokyo), and skin AGEs score via AGEs sensor
device (RQ-AG01J: Sharp Life Sciences, present Air Water
Biodesign, Kobe, Hyogo, Japan). Post-ingestion tests included
a survey of lifestyle- related and skin conditions, skincondition measurement, and AGEs score. In both the preingestion test and the post-intake test, female subjects washedtheir face 20 minutes or more prior to the test to remove
cosmetics, and performed skin diagnostic measurements after
acclimation. The test period was from June 2019 to July 2019.

Dewaxed brown rice (DBR)
DBR is brown rice from which rice husks havebeen removed from whole rice that have been dried after
harvesting, and the wax bran layer that covers the surfaceof the brown rice has been removed by special processing( Fig. 2). The non-edible part of the rice husk, the wax layer,hinders water absorption, while the bran layer contains
various nutrients. The sub-glue powder layer is locatedbetween the starch layer and the bran layer, the nutritional
components of brown rice are concentrated, it has a uniqueflavor and sweetness, and the taste is also preferable. Subaleurone-remaining wash-free rice (SARFR) has a part of
the wax layer and the bran layer removed, but DBR only
removes the wax layer, thus being closer to brown rice.
The nutritional components in rice differ depending on
the amount of cultivated soil bacteria and the rice milling
process. In general, DBR is four times higher in vitamin B1,
fourteen times higher in vitamin E, and seven times higher in
dietary fiber than ordinary polished rice ( Table 1).
Brown rice is covered with a highly waterproof layer(wax layer) so that it does not germinate as seeds by absorbing
water until the growing conditions are met. The strong
waterproofing of the wax layer hinders water absorption,and the rice grains do not swell sufficiently, which can makethem difficult to eat. It usually takes about 20 hours to soak
before cooking rice. This time is longer than the immersionof polished rice for about 1 hour. Since the presence of the
wax layer hinders water absorption, the rice does not expand
sufficiently even when cooked, and the rice grains are hard.
Therefore, it has low digestibility even though it contains
high nutritional value. On the other hand, since DBR removes
the wax on the surface, water is easily absorbed during
soaking and cooking rice, as with polished rice. The starchof rice is pregelatinized and swells well when heated duringcooking, so the color is whitish like polished rice, and the rice
is cooked into plump rice with good digestion and absorption.

Evaluation item
Skin index

The skin indices included functions, skin age, overallskin health, pores, wrinkles, moisture, elasticity, skin tone,
pigmentation (epidermis layer, dermis layer), oil content,
and porphyrin, that were measured via Clreo-Pro as in theprevious report 6).

Germ
Base of germ
Wax layer
Bran layer(Deep layer:
Aleurone layer, etc.)

Sub-aleurone
layer

Starchy
endosperm

Sub-aleurone
layer
Starchy
endosperm

Rice-hulls (chaff)

DBR

Whole rice!"#$%'

Fig. 2. Structure of rice and DBR.

SARFR

DBR, dewaxed brown rice; SARFR, sub-aleurone-remaining wash-free rice.

_ 31 _

Effects of Dewaxed Brown Rice

Table 1. Ingredient composition of polished rice, brown rice and DBR.

Dietary fiber

Polished rice

Traditional brown rice

DBR

0. 5 g

3.0 g

3. 5 g0.08 mg

0.41 mg0.36 mg

Calcium

5 mg

Vitamin E (α-Tocopherol equivalent)

0.1 mgγ-oryzanol

0 mg

Vitamin B1
Niacin9 mg

1. 2 mg

1. 2 mg

6. 3 mg
46 mg

6 mg

1.4 mg
3.1 mg33 mg

Data are shown as nutrient content per 100 g. polished rice, traditional brown rice, data according to Standard Tables of Food Composition in Japan(value before rice washing); DBR, values after non-washing (according to the Food Environment Inspection Association); γ-oryzanol, survey by Japan
Food and Fat Inspection Association; diaetary fiber, there may be a difference since the content value differs depending on the brown rice used as theraw material; DBR, Kinme dewaxed brown rice.

AGEs measurement
The AGEs score was measured using AGEs sensors 10, 11).

caused by ingestion of the test product (Fig. 1). There were
no dropouts in the control group. The reason for dropping out
was due to personal reasons.

Subjective symptoms

Subjective symptoms

The contents of the questionnaire were questions aboutchanges in eating habits, lifestyle habits (exercise, sleep,bowel movements, drinking, smoking, and mental stress),and skin conditions. The average value of compliance (theintake rate of the test product) was calculated based on thequestionnaire.

No notable findings were found regarding lifestylerelated symptoms (exercise, sleep, bowel movements,
drinking, smoking, stress) and subjective symptoms related
to skin condition. No adverse symptoms were observed.

Statistical analysis

Table 2 shows the measurement results of the skinindex. The rejuvination in skin age (change amout) was
significantly greater in the DBR group than in the control,
and was improved in the DBR group (p = 0.023, Fig. 3-a).
Skin age was significantly improved in the DBR group in
women (p = 0.011, Fig. 3-c), but not significantly in men(Fig. 3-b).
There was a significant difference in the change ratein wrinkles between the groups, which was significantly
improved in the DBR group (p = 0.039, Fig. 4-a). No
significant difference was observed in males (Fig. 4-b), but
in females ( p = 0.049, Fig. 4-c). Regarding the change rate
in porphyrin, there was no significant difference between
the groups for men and women ( Fig. 5-a, b), but there was asignificant improvement for women in the DBR group (p =0.044, Fig. 5-c)

For analysis, a software SPSS (Statistics25: IBM Japan,
Chuo-ku, Tokyo, Japan) was used to perform paired-t test or
Wilcoxon signed rank test. A risk rate of less than 5% was
defined as a significant difference.

Ethical standards
This study was conducted in compliance with the
Declaration of Helsinki (revised at the 2013 WMA Fortaleza
General Assembly) and the ethical guidelines for humanbased medical research (notification by the Ministry of
Education, Culture, Sports, Science and Technology [MEXT]
and Ministry of Health, Labour and Welfare [MHLW]). This
research obtained the approval of the Ethical Committee of
the Society for Glycative Stress Research (GSE 2019-004),
which has discussed the ethics and validity of the study.
The clinical trial for this study was pre-registered (UMIN# 000037017).

Results

Intake compliance

The compliance of the DBR group was 87.5 %, 1 outof 45 patients (dropout rate 2.2 %), and no dropouts were

Skin index

Measurement of AGEs
There was no significant change in skin AGE
fluorescence intensity before and after the test in bothgroups, and there was no significant difference in the amountof change between the groups (Table 2).

SafetyNo adverse events thought to be caused by the test
product were observed during the observation period.

_ 32 _Glycative Stress Research

Table 2. Results of skin condition and AGE fluorescence.
Before ingestion

One month afteringestion

Comparison between
groups (by variation)

Mean ± SD

Mean ± SD

vs. control- 2.8 ± 11.9

0.885

1.4 ± 7.3

0.300

1.3 ± 4.4

0. 5334.6 ± 7.7

0.615

31.4 ± 7.7
32.8 ± 9.930.3 ± 6.4

0.393

62.6 ± 4.4

0.630

43.8 ± 4.9
42.7 ± 7.7

4 4.8 ± 5.0

0.973

50.5 ± 12.4

0.405

24.2 ± 9.2
22.2 ± 1.6

23.8 ± 8.8

0.023

0.46 ± 0.05

0.260

DBR

Age (year)

23.8 ± 8.7
22.0 ± 1.2

Control
DBR

Pores (%)

-0.3 ± 12.6
-2.0 ± 13.5

Control
DBR

WrinklesPigmentation (PL)stratum corneum (%)
Pigmentation (UV)
stratum corneum (%)
Porphyrin

3.5 ± 8.8
0.5 ± 6.1

Control
DBR

2.6 ± 4.7
1.9 ± 4.1

Control
DBR

6.2 ± 8.8
3.9 ± 5.3

Control
DBR

Control
DBR

Skin tone

61.8 ± 4.7
61.7 ± 4.7

Control

Elasticity (angle)
Skin health score

DBR

Control
DBR

45.0 ± 12.9
47.3 ± 9.6

Control
DBR

Skin age (year)

Control
DBR

AGE Score

0.44 ± 0.06
0.44 ± 0.21

Control- 4.6 ± 11.3

- 0.4 ± 4.9
0.8 ± 3.7

2.8 ± 5.0

30.1 ± 10.6

62.8 ± 4.8
43.6 ± 5.2

50.9 ± 10.0

22.0 ± 1.6

0.46 ± 0.05

DBR, dewaxed brown rice; AGE, advanced glycation endproduct; PL, polarized right; UV, ultraviolet; SD, standard deviation; skincondition measured by Clreo-Pro (Fujitex); AGE score measured by AGEs sensor (Sharp); DBR group, n = 43; the control group, n = 22;
Statistical analysis by Student’s t test.

a) Total

Skin age(year)

0.0b) MaleDBR

Control

- 0.1
- 0.2
- 0.3
- 0.4
- 0.5
- 0.6
- 0.7
- 0.8

p = 0.023

0.0c) Female
DBR

Control

0

- 0.1

- 0.1

- 0.2

- 0.2

- 0.3

- 0.3

- 0.4

- 0.4

- 0.5

- 0.5

- 0.6

- 0.6

- 0.7

- 0.7

- 0.8

- 0.8

DBR

Control

p = 0.011

Fig. 3. Change of skin age.
a) Total, DBR group, n = 43; the control group, n = 22. b) Male, DBR group, n = 25, the control group, n = 13. c) Female, DBR group,n = 18 the control group, n = 9. Skin age evaluated by Clreo-Pro (Fujitex). Results are expressed as mean ± SEM; Statistical analysis by
Wilcoxon signed rank test. DBR, dewaxed brown rice; SEM, standard error mean.

_ 33 _

Effects of Dewaxed Brown Rice

Wrinkle change (%)a) Totalb) Malec) Female

1.50

1.50

1.25

1.25

1.00

1.00

p = 0.049

1.50
p = 0.039

1.25
1.00
0.75
0.50

0.75

0.75

0.50

0.50

0.25

0.25

0.25

0.00

0.00

0.00

DBR

DBR

Control

DBR

Control

Control

Fig. 4. Change of wirinkles.
a) Total, DBR group, n = 43; the control group, n = 22. b) Male, DBR group, n = 25, the control group, n = 13. c) Female, DBR group,a) Totalb) Malec) FemalePorphyrin change (%)

n = 18 the control group, n = 9. Winkles are evaluated by Clreo-Pro (Fujitex). Results are expressed as mean ± SEM; Statistical analysis
by Wilcoxon signed rank test. DBR, dewaxed brown rice; SEM, standard error mean.

1.50

1.50

1.50

1.25

1.25

1.25

1.00

1.00

1.00

0.75

0.75

0.75

0.50

0.50

0.50

0.25

0.25

0.25

0.00

0.00

DBR

Control

p = 0.044

0.00

DBR

Control

DBR

Control

Fig. 5. Change of porphyrin.
a) Total, DBR group, n = 43; the control group, n = 22. b) Male, DBR group, n = 25, the control group, n = 13. c) Female, DBR group,n = 18 the control group, n = 9. Winkles are evaluated by Clreo-Pro (Fujitex). Results are expressed as mean ± SEM; Statistical analysis
by Wilcoxon signed rank test. DBR, dewaxed brown rice; SEM, standard error mean.

Discussion
Whole-grain brown rice contains a variety of nutrients.
When brown rice was the major staple food in Japan,
vitamins, i.e. vitamin B1, could be supplemented, however,during the Genroku era (1688-1704), beriberi became popularin Edo, where polished rice was prevalent, this caused what
was called "Edo illness." Later, from the Meiji era (18681912) to the Taisho era (1912 -1926), beriberi developed inso many people that it was said to be one of the two major
national diseases along with tuberculosis. In the Showa era(1926-1989), when the "Funpu Rice Milling Method" wasdeveloped in 1955, the "over-polished rice" began to spread,beriberi and other illnesses had then begun to be seen mainly
among young people with unbalanced diets and persons withchronic diseases. This method (Funpu meaning blasts) is a
modification of the conventional friction type rice millingmachine, which uses the high pressure inside the machine(200 to 300 g/cm 2) to increase the frictional force between
rice particles and polishes them, followed by blowing off theadhered bran and residues with a blast (30 m/sec or more).
Although brown rice contains various ingredients and isclearly superior to polished rice in terms of nutrition, it isdifficult to cook, has a taste and texture different from that ofpolished rice, and is difficult to digest. Brown rice has moved
away from its main staple food position.
At this time, we conducted a clinical trial for university
students using DBR, which was developed to reduce thedisadvantageous characteristics of brown rice and takeadvantage of it. In the group (4 3 subjects) who took DBR
150 g or more per day for 1 month, intake compliance wasmaintained as high as 87. 5 %, no adverse events wereobserved, and skin age, an index of skin condition, wasimproved significantly compared with the control (22subjects). These actions are due to the functional ingredientscontained in brown rice. Brown rice contains B vitamins
such as vitamins B1, B2, B6, nicotinic acid, patent acid,inositol, choline, and folic acid. Other components will be
described below.

_ 34 _Glycative Stress Research

The ingredients of brown rice
γ-Oryzanol

γ-Oryzanol is a combination of ferulic acid and foodsterols and is the main component of rice bran oil. Excessive
intake of animal fat causes ER stress in pancreatic β cells
and nerve cells in the hypothalamus, and γ-oryzanol has theeffect of relieving these ER stresses 9). As a result, it exerts acentral effect that helps improve tension, anxiety, depression,
and withdrawal from animal fat dependence. In the pancreas,
it enhances β- cell glucose-responsive insulin secretion
and reduces α-cell glucagon hypersecretion. These actions
lead to the reduction of glycation stress. It is known that the
intake of brown rice diet improves animal fat addiction, and
it is presumed that γ-oryzanol plays an important role inthis 10). Supplements containing γ-oryzanol have also beendeveloped 11).
Brown rice may contain unknown functional ingredients.
It has been reported that the triterpene alcohol and sterol
fractions (TASP) contained in the oil-soluble fractions
in rice bran have an effect of ameriorating postprandial
hyperglycemia 12) and an effect of suppressing high-fat
diet- dependent obesity 13). As its mechanism of action, it is
supposed that TASP suppresses the increase in postprandial
blood concentration of glucose-dependent Insulinotropic
polypeptide (GIP), a gastrointestinal hormone, and interfereswith the translocation of Sodium-dependent Glucose
Transporter 1 (SGLT1), a glucose transporter, onto the cell
membrane 14).

Ferulic acid
Ferulic acid has strong antioxidant power and weakcytotoxicity 15). It is experimentally known to have an effectof reducing amyloid β oligomers, and is expected to have ananti-dementia effect in humans 16, 17). Regarding glycative
stress, ferulic acid could not confirm the formation
inhibitory effect on AGEs in our laboratory, and the amountof fluorescent AGEs tends to increase 18). Further studies
are needed on the effects on AGEs other than fluorescent
AGEs.

Dietary fiber
Rice bran and germ are rich in dietary fiber. It is an
essential substance for "healthy intestinal-brain correlation"that contributes to the healthy growth of the intestinal flora
and the enhancement of brain mental function. It is an
essential substance for the healthy growth of the intestinal
flora and the homeostasis of the "gut-brain axis" that
contributes to the enhancement of brain mental function.
Dietary fiber acts as a probiotic to promote the growth ofbeneficial bacteria in the intestinal flora, and increases, inparticular, the number of bacteria that produce short-chain
fatty acids, i.e., acetic acid, butyric acid, and propionic acid.
Short-chain fatty acids promote body temperature elevation,
heart rate increase, lipolysis in adipose tissue via specificreceptors (i.e., GRP41), and have the effect of increasing basal
metabolism when overdosed 19). Dietary fiber has the effect ofsuppressing postprandial hyperglycemia 20). Both actions canbe expected to have the effect of reducing glycative stress.
GABA is contained in a trace amount in brown rice andacts as an inhibitory neurotransmitter in the body. It is related
to long-term object recognition memory and working memory,and it has been reported in animal experiments that it has aneffect of reducing mental and physical stress 21) and an effectof improving memory deterioration after head injury 22).
Human clinical trials have reported the antihypertensive
effect of GABA-containing koji amazake 23, 24).

Phytic acid
Phytic acid, also called inositol 6-phosphate, has anantioxidative effect, and is known to suppress the increasein plasma uric acid levels, prevent renal stone formation, andreduce serum cholesterol 25). In addition, it has been pointed
out that it may reduce the risk of carcinogenesis 26). Althoughphytic acid has a chelating effect, the content of brown rice
does not deplete the useful minerals.

Lipopolysaccharide (LPS)
Brown rice contains LPS. This is a component common
to the surface membranes of Escherichia coli and Salmonella,
however, LPS is not pathogenic. When a small amount of
LPS enters the intestinal tract together with brown rice, thebowel movement becomes active and activates macrophages
having a bacterial phagocytosis 27). LPS is known to increse
the secretion of mucus and bactericidal substances from theintestinal mucosa. As a result, innate immunity is strengthened.
Also, LPS prevents the onset of allergic diseases such aspollinosis and reduces the symptoms 28). It has been reported
that it stimulates microglial cells to stimulate the phagocytosisof amyloid β in the brain 29).

The mechanism and components involved in
improving skin condition
Next, we will discuss the mechanism and components
involved in improving skin condition observed by DBR
ingestion. In general, skin condition changes due to aging andvarious environmental factors. Among these factors, the effectof ultra violet (UV) exposure is the largest. This is called
photoaging, and the main mechanism is oxidative stress 30). As
menopause approaches, complaints of skin problems increase
as estrogen secretion decreases. However, since the subjects
this time are young people, the involvement of these factors
is small. It is presumed that the effect of glycative stress isgreater than these. When collagen and elatin that make up theskin are denatured by glycative stress, elasticity is reduced,
thus causing skin sagging. Accumulation of AGEs causes
yellowing in skin. Glycation of keratin and filaggrin (a natural
moisture factor) increases transepidermal water loss (TEWL)
and reduces the moisturizing function. A decrease in filaggrin
promotes the breakdown of the skin barrier and increases therisk of developing atopic dermatitis 31).
Effects known for brown rice (including processedbrown rice) include the amerioration of triglyceridenia andtotal cholesterolemia 32, 33), improvement of postprandial
hyperglycemia 34, 35), reduction of fasting blood glucose 36) andHbA1c 37, 38) and reduction of visceral fat in metabolic syndrome39), which are all actions that reduce glycative stress. Dietaryfiber is known to have an improving effect on the intestinal
flora 40, 41), and promotes basal metabolism via elevated_ 35 _

Effects of Dewaxed Brown Rice

production of short- chain fatty acids 19), thus contributing
to the reduction of glycative stress. The restoration of theintestinal flora leads to the improvement of skin condition
via improvement of bowel movement 42). In addition, forphotoaging 30), which is a major cause of skin disorders,antioxidants such as ferulic acid reduce oxidative stressassociated with UV exposure. As a result of these mechanisms
acting in an integrated manner, it is possible that they had afevorable effect on skin condition (Fig. 6 ).

years. There are many cases with a latent predisposition toeasily produce the IgE antibody, and it is expected that it willaffect the skin condition of young people in particular. It is
possible that the allergic symptom-reducing effect of LPS
in brown rice 28) had a positive effect on this problem. The
details of the action mechanism of LPS for allergy relief
remains unclear. Further research is needed in the future.

The effect of sntioxidant ferulic acid and dietaryfiber that regulates the intestinal environment

The test product (DBR) is processed from brown riceto
be easy to eat, leaving nutrients by removing only the wax
layer of the epidermis and the outer layer containing a large
amount of indigestible fiber.
In SARFR, the wax layer and part of the bran layer
are removed, while, in DBR, only the wax layer is removed,
which is closer to brown rice and rich in nutrients. Since
dietary fiber is contained in a slightly large amount, the effectvaries from person to person, and some people can accept
the positive effect, while others may exhibit discomfort due
to dietary fiber.
Comparing the previous report using SARFR 6) with thisstudy, there was no difference in intake compliance between
DBR and SARFR, and there was no safety problem in either
case.
Furthermore, both showed improvement in skin condition(skin age as an index), and there was no difference in themagnitude of the effect between the two. The feeding period
was one month in this study. If DBR was taken for a longer
period of several years or more, it might be more effective.
When individuals want to start a processed brown rice diet,they should choose DBR or SARFR according to their taste
and physical condition.

There are also some reports on the effects of DBR.
It contains about 100 times more LPS than polished rice,and LPS activates macrophages mainly via TLR4 3). LPS isderived from symbiotic bacteria and is also abundant in thebran layer. Animal experiments have shown that ingestion of
DBR powder into antibiotic-induced constipation model micesignificantly suppressed weight loss and improved bowel
movements compared to control mice to which antibiotics
alone were administered 4). In pollinosis model mice, ananti-allergic effect was observed by the supplemented feedof DBR subglue powder layer extract as compared with tothe control (mice administed with no additive feed) 28). In aclinical trial in humans, the cognitive ability evaluation scale,
HDS-R (Revised Hasegawa's Dementia Scale), improved asa result of ingesting DBR for six months in the elderly, wherean association was found between DVR intake and the scalescores 43). Brown rice, which is rich in LPS, is expected to be
useful as a staple food that helps maintain good health.
One of the causes of skin disorders is allergic disease.
Adult atopic dermatitis has been on the rise in the last 30
years, it is said that it has finally reached a plateau in recent
PPHG
TG LDL-C
Fat-dependence

LPS

Allergic
Reaction

Comparison of DBR and SARFR

Glycative
StressSkin

Ferulic acid

DBR

Collagen fiber

Yellowness

Dark spots

AGE deposit

Melanin

Oxidative
Stress

Keratinocyte

Glycation
Dietaryfiber

Filaggrin glycation
gene expression

Dysbiosis

Elasticity

Crosslinkformation

Fig. 6. The possible suppressive actions by DBR.

Moisture

DBR, dewxwd brown rice; AGEs, advanced glycation endproducts; PPHG, post-prandial hyperglycemia: TG, triglycemide, LDL-C, lowdesity lipoprotein-cholesterol; LPS, lpopolysaccharide;_ 36 _Glycative Stress Research

Conclusion

SafetyBrown rice, DBR, and polished rice are basically staple
foods. Therefore, they have abundant food uses and are fully
guaranteed for food safety. There was a time when pesticide
residues in brown rice were regarded as a problem, but all
recent test results are within the standard values ​​44, 45). Even if
a small amount of foreign matter adheres to the outer layer,
it will be scraped off by special rice milling, so no problem
will occur. No adverse events related to DBR have beenreported in this study or in past clinical studies 42). After all,it was judged that there was no problem with the safety of
DBR.
Abscisic acid is known as a phytohormone that regulates
plant growth and physiological activity, and is present in allplants including brown rice. It has an anti-inflammatory
effect and is a food ingredient expected for impaired glucose
tolerance and inflammatory bowel disease 46, 47). In a report 48)
that integrated information and evaluated the safety of theingestion of brown rice, indicating that the harm event was
not reported, it is considered that danger is hardly a problem
and the health effect is greater.

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As a result of ingesting a test meal (DBR) of 150 g ormore once a day for one month for university students andstaffs, no gastrointestinal symptoms were observed, intake
compliance was good, and a significant skin condition
improving effect was observed. It was suggested that DBR
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Conflict of interest declaration.
This research was supported by Toyo Rice Co., Ltd.

Acknowledgments
This research was supported by the unincorporated
association: Research Foundation of Crude Drug gained
from the same source of Medicine & Food.

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