HEALTH AND NUTRITION NEWSNo. 15
March 15, 2006

Table of Contents

Prefatory Note
Development of applied nutrition for human health………………………...………………Teiji Nakamura

CURRENT RESEARCH PROJECTS
Laboratory of Informatics on Health and Nutrition…….. ……..……………………….……Kouichi Hirota

THOUGHTS ON HEALTH AND NUTRITION RESEARCH
Reference Exercise and Physical Activity Quantity (REPAQ) for Health Promotion ~Physical activity,
exercise and fitness~………………………………………………………………………........ Izumi Tabata

RESEARCH FINDINGS
Evaluation of the correlation between amount of Curcumin intake and its physiologicaleffects…………………………………………..………………………………………………Junichi Nagata
Effect of Dietary Factors on Incidence of Type 2 Diabetes: A systematic reviews of cohort
studies………………………………………………………..…..……Kentaro Murakami, Satoshi Sasaki
Association between Histidine intake and energy intake………....……Hitomi Okubo, Satoshi Sasaki
Puerariae radix prevents bone loss in castrated male mice…………….…………….….Yoshiko Ishimi© National Institute of Health and Nutrition

Prefatory Note

Development of applied nutrition for human health
Teiji Nakamura, PhD, RD.
Chair, School of Nutrition & Dietetics, Faculty of Health and Social Work,
Kanagawa University of Human Services.
President, The Japan Dietetic Association
original purposes of “for human beings”. On theother hand, other Schools would accumulate thestudies on the methods to relieve the pains anddisease burdens of injured/sick persons in orderto theorize them. None of these Schools has amaterial like “nutrients”, and they would totallytarget humans. Although these fields are notneatly systematized as the nutrition sciences,
they never turn from humans.
On the other hand, in the field of nutrition
sciences, the association between foods/nutrientsand human life behavior are theorized, and then,the systematized principles are applied in theclinical field. The priorities of nutritional specialists
are the principles of nutrition sciences, and thus,
the basic researches to explore them are wellemphasized, whereas the practical researches toseek for the methodologies to solve the actual
contradictions/problems tend to be neglected. In
the education for dietitians/registered dietitians,
they are trained to apply the nutrition sciences in
the practical field, following the principles strictly.
However, when we treat the injured/sick persons
individually, we often get embarrassed to see thecomplexity and variability of humans. This could
be more complex, when we take into account of,
not only the health and nutritional status of eachpatient, but also his/her view of life and daily life.
With the revision of long-term care insurance
system in Japan, the registered dietitians are now
able to meet and work directly with each patient at
bed side. I expect that, from now on, the nutrition
researches that reflect the opinions from the field
will be enhanced.
The NIHN has been historically a core of thenutrition researches in Japan, as well as a basefor the nutritionists. In order to respond to thenutritional/dietary problems among human beings,
I expect that the collaboration and partnership
between the NIHN and dietitians would further
develop hereafter.

“How should we choose foods, and how much
can we take them, so that we can have healthy
and happy life?” This is a simple question, but isan origin of nutrition sciences and still a base of
research objectives. Fortunately, humans beings
discovered “nutrients” and have explored themethods to investigate the associations between
diets and vital activities scientifically. In addition,
the roles of nutrients and recommended intakes
were explored and some nutrients weresynthesized. Now, it is possible not only toprovidethescientificallyacknowledged
appropriate diet, but also to supply our bodies
directly with each nutrient.
Some time ago, I listened to the performanceby a pianist whose intestine had been resected
due to the Crohn’s disease, and that he has nottaken any foods by mouth for about 10 years.
Now, it is possible to take necessary energy andall the nutrients, beyond the limits of appetite andcapacity of taking foods. Yet, from ourexperiences, we know that the patients became
lively and talkative with more smiles, once they
restart to take foods by mouth, even very small
amount only. Neither their nutritional intake reachthe required amounts nor the results of physicalexamination are improved, but apparently, thepatients become better.
I used to work for a hospital and am now
engaged in education and research at a university
from 3 years ago. At the present university, there
are four Schools; School of Nutrition & Dietetics,
School of Nursing, School of Social Welfare andSchool of Rehabilitation. Our mission is to carryon the human services in collaboration with these
Schools, by removing barriers among them. I
have been seeking what the nutrition sciences
should be, by discussing with staffs of other
Schools. Since the nutrition sciences have theuniversal materials called “nutrients”, it isscientifically well systematized. I am anxious,
however, that this may make us to disregard the2* The original Japanese version was translated by
Office for International Collaboration, NIHN

Current Research Projects
Laboratory of Informatics on Health and Nutrition
Kouichi Hirota
Division of Health Informatics and Education
Now, it is quite easy to search information on the

The search sites, like Google, are now moreweb, mainly due to the improvement of algorithm

user-friendly than the past ones in 20th century.

used in the program of search sites. I guess

Yet, it must be noted that the basis of this search

everybody has heard of the search site “Google”

algorithm is a kind of popularity polls. So, the sites(http://www.google.co.jp). The algorithm used inwith more access are higher in the search rank.

this

which

However, we can not say that the popular sites

dramatically changed the internet search. It

have fewer mistakes than unpopular ones. It isshould be difficult to imagine, but the site searchpossible that they might be popular by the false

before 1998 was literally “mountain in labor”

information written in their sites.

site

was

developed

in

1998,

accompanying lots of efforts with little outcomes.

While our survey found that there is a definite

Here, our Laboratory works on the researches torelation between the standard of site reliability

search and organize the health and nutrition

and the scientific reliability of nutrition information,

information effectively on the web.

there are also some exceptional cases. The mostI myself have been involved in these researches

accurate evaluation method of site reliability is tosince 1995, before the present Laboratory was

be checked by the experts, though it is notestablished.

unrealistic with respect to the scale of websites

Since

the

internet

searchenvironment was poor at that time, the main focus

and speed of development.

was to develop the algorithm to search the usefulsites.

In

2001

only

reliableestablished, however, it was no longer important

we have been working on the development of

to search just useful information because theweb systems in collaboration with other Divisions“Google” had been launched some years before.

at the NIHN (e.g. Information system on safety

In

internationaland effectiveness for health foods). There are

academic journals established the system toalso other tools like the nutrition education tool ofbrowse the PDF version of articles. We therefore“Self-learning system for improving lifestyle

started the researches on the system to collecthabits” and “Nutrition Kids” for children. Since

and browse the latest research findings from thethese tools are currently under development, wescientific information sites. Later, the following

expect to introduce them more in details later on.

websites

Laboratorytransmitting

information could improve the reliability of website,

the

this

that

was

addition,

when

Assuming

offunctions were added to the above system;
machinetranslation

system,automated

information collection from France, Germany, Italy,
Spain, Korea and China, and daily automatedcollection of the latest articles on health foodsfrom the database of National Library of Medicine.
The outputs of this system can be seen in our
website: http://humpty.nih.go.jp (Japanese only)
In addition, we also undertake the researches on
the reliability of internet information.

3

Thoughts on Health and Nutrition Research
Reference Exercise and Physical Activity Quantity (REPAQ) for Health Promotion~ Physical activity, exercise and fitness ~Izumi Tabata
Division of Health Promotion and Exercise
Ministry of Health, Welfare and Labour reviewed

significantly

the “Recommended exercise Allowances fordiabetes,

health promotion” in 2005, after 16 years of

diseases.

reducethehypertension

risk
and

of

developing

ischemic

heart

the

As for Vo2 max (an index of the endurance), the“Reference Exercise and Physical Activity

average values in Japanese were employed as

Quantity (REPAQ) for Health Promotion ~the standard ones. In addition, the qualitative

Physical activity, exercise and fitness~” for the

standard was used for muscle strength, that is,nations“approximate

enactment

in

aged

1989,

20-69

and

years

establishedtodefinetheaveragevalues”.

“Exerciserecommended physical activity/exercise level. As

guidelines for health promotion” for the nations as

described below, the recommended levels arewell as the guidebook for the instructors were

now set as1)“23 METs ⋅ hour per week” foralso prepared, which will be used for the trainings

1)on physical activity and exercise as a part ofphysical activity and “4 METs ⋅ hour per week”

health activities in the next five years.

for exercise.

And, the educational activities for the nations are

In order to establish these values, a systematic
review of the international/domestic articles wasgoing to be implemented from this year.

done to identify the physical activity/exercise level1) For each activity/exercise, time for 1 unit is defined, andand physical fitness (Vo2 max) that would

the target units are shown as the total sum during a week

Reference Exercise and Physical Activity Quantity (REPAQ) for Health Promotion~ Physical activity, exercise and fitness~(Summary draft)
Office for Lifestyle-related Diseases Control
General Affairs Division, Health Service Bureau
Ministry of Health, Welfare and Labour
We reviewed the “Recommended exercise allowances for health promotion, and defined
the ideal levels of the physical activity and exercises for the nations aged 20-69 years.
For the persons who attempt for health promotion mainly by the physical activity, the target
should be 8,000-10,000 steps daily, and for those who attempt for it mainly by exercise,running or tennis for 35 min/week or quick walking for one hour can be recommended.
1.

2.

3.

4.

5.

This report was made by the preparation panel for the recommended exercise allowance and exercise guideline
established on 8 August 2005, with the basis of the “Recommended exercise allowances for health promotion (1989)”
to which the presently available scientific evidences were added.
The main differences from the previous “Recommended exercise allowances for health promotion (1989)” are; 1)
standard values are shown for each of physical activity/exercise level and physical power (Vo2 max) based on thesystematic review of international/domestic articles, 2) associations between the lifestyle-related diseases control andphysical fitness (including muscle strength) were also investigated.
The newly defined standard values of physical activity/exercise level for health promotion are;a. For physical activity: 23 METs ⋅ hour/week (Activities with intensity ≥ 3METs should be done for 60 minutes/day.
If most of the activities are related to walking, the corresponding level is about 8,000-10,000 steps daily)b. For exercise: 4 METs ⋅ hour /week (e.g. quick walking for about 60 minutes, running/tennis for 35 minutes).
Standard values of Vo2 max (ml/kg/min) for health promotion, according to gender and age group.
20-29 years
30-39 years
40-49 years
50-59 years
60-69 years
Male
40
38
37
34
33
Female
33
32
31
29
28
This report briefs the associations between health and physical activity/fitness based on the scientific evidences. In
order to accumulate new knowledge, it is necessary to promote the related researches to revise the report regularly.

4

Latest Research
Correlation between amount of Curcumin intake and its Physiological effects.
Junichi Nagata (Division of Food Science)
Termeric is at the top in sales rank of so-called health foods in Japan, and is well known as one of therepresentative health foods. It is a kind of Zingiberacea, a perennial plant, and grows in tropic and subtropic
regions, centering on the southeast Asia. It is said that there are about 50 species of termeric in the world. Of
which, Curcuma longa (ukon), Curcuma aromatica (kyouou) and Curcuma zedoaria (gajyutsu) are therepresentative ones in Japan (Figure 1). The root tuber and rootstock are the foods related to “ishoku dogen(=taking foods in a healthy way for better health)”, which have been used as a dyestuff, spice, Chinese herbal
medicine and ancient Indian medicine since the ancient times. They came first to Ryukyu (=Okinawa) from
China during the Heian period (795-1185), and spread gradually across the country. Since then, many
experiences on the effects of termetic have been orally handed down to the generations, including theimproved liver function, maintenance of stomach and increased bile acid secretion.
Termeric consists of various components such as minerals (P, Fe, Ca, K, Mg), dietary fiber, curcumin(turmeric), curcumen, azulene, camphor and cineole. In particular, the curcumin content of Curcuma longa
was 3-5%. Curcumin was deemed to be the representative active component that would contribute to the
antioxidative function and improvement/maintenance of liver function.
In this study, focusing on curcumin, we investigated the associations between amount of curcumin intake
and its effectiveness and safety on rats. Male Wistar rats were fed the experimental diets containing 0.5mg(x1), 5mg (x10), 50mg (x100) curcumin per 100g body weight for 28 days, while the control group received
the curcumin-fee diets. The basal daily amount of curcumin in rats was estimated by weight conversion basedon the recommended daily intake for humans. And, the physiological effects on indices of liver function,
serum and liver lipid profiles and other biochemical parameters were examined.
Serum HLD-cholesterol concentrations of rats fed curcumin diets were significantly higher (p < 0.05) thanthat of control group. As for serum TG concentration, it decreased significantly in a curcumin dose-dependent
manner (Figure 2). On the other hand, there was no significant effect on growth and indices of liver function.
In conclusion, this study explored that curcumin was the component that would effectively improve the serum
lipid profiles.
Since turmeric consists of various other components, it is still unclear how much of the physiological effectsof turmeric are actually derived from curcumin. There remain lots to be investigated on the effectiveness andsafety of turmeric, and further studied will be necessary to investigate these mechanisms hereafter too.

controlx1 curcumin dietx10 curcumin dietx100 curcumin diet

Total chol.
Figure 1. Curcuma longa (left), Curcuma
aromatica (center) and Curcuma zedoaria (right)

HDL-chol.

TG

Figure 2. Serum lipid profiles ofmaintained on different curcumin diets

rats

Evaluation of the Correlation Between Amount of Curcumin Intake and its
Physiological Effects in Rats
Food science and technology research. 2005;11(2):157-160.
Nagata J and Saito M
Division of Food Science, National Institute of Health and Nutrition, Tokyo, Japan.

Abstract:
We examined the correlation between amount of curcumin intake and its physiological effects
on indices of liver function, serum and liver lipid profiles in rats. Animals were fed diets containing 0.5, 5 and50mg curcumin per 100g body weight for 28 days.
HDL-cholesterol concentrations of rats fed curcumin diets were significantly higher (p < 0.05) than those of
the control group, and serum TG concentration of rats fed the x100 curcumin diets was significantly lower (p< 0.05) than that of the x1 curcumin group. Serum TG concentration of rats fed curcumin diets tended todecrease in a curcumin dose-dependent manner. These results indicate that curcumin intake can improve
serum lipid profiles effectively.
5

Latest Research
Effect of dietary factors on incidence of type 2 diabetes: a systematic review of cohort studies.
Kentaro Murakami, Satoshi Sasaki (Project of Scientific Evaluation of Dietary Reference Intakes)
Now, it is estimated that there are at least 6.8 million people with type 2 diabetes in Japan. Since it is quite difficult to treat
diabetes completely, the primary prevention of the disease is of significant public health importance. Although many lifestyle
related factors are associated with the development of type 2 diabetes, food and nutrition may also play an important role inits cause. We, therefore, systematically reviewed the published cohort studies examining the effects of dietary factors on theincidence of type 2 diabetes, so as to compile the currently available scientific evidences.
The MEDLINE (PubMed) was used to search the articles. The following keywords were used; (“diet” OR “dietary” OR“nutrient” OR “consumption” OR “intake”) AND (“diabetes” OR “diabetic”) AND (“prospective” OR “follow-up”). Of theretrieved articles and their reference lists, only articles that met all the following criteria were identified: 1) the endpoint was
the incidence of diabetes; 2) follow-up procedure and length and the definition of the incidence of diabetes were clearly
documented; 3) quantitative (including consumption frequency) assessment of food and/or nutrient was conducted; 4) results
were shown using the relative risk (RR) (and 95% confidence interval (CI)); and 5) factors used when calculating multivariate
RR were clearly indicated.
As a result, 15 individual cohort studies (31 articles) were retrieved, all of which were carried out in Western Countries (10studies in USA, 3 in Finland, 1 in Netherlands and 1 in Sweden). The
Table 1. Summary table of 15 cohort studies:
nutrient and food with preventive/promoting effects number of subjects (n=895-85,060), follow-up length (5.9-23 years), theTotal number
Significant
number of diabetes cases (n=74-4,085), dietary assessment instrumentof study
association
used (simple food questionnaire, food frequency questionnaire, foodPreventive factor
frequency interview, diet history interview and 24-h recall methods),
a. Nutrient
procedures for ascertaining of the incidence of diabetes (questionnaire,oral glucose tolerance test, fasting glucose level, death certificate,
Vegetable fat
63
Polyunsaturated
nationwide registry) varied among articles. A total of 99 dietary factors
62
fatty acid
were examined in the 31 articles.
Table 1 shows the nutrients and foods/food groups for which theDietary fiber
6
3
preventive or promoting effects of type 2 diabetes were shown in more
Cereal fiber
8
6
than 2 articles.
Magnesium
84
For the evidence-based primary care and treatment of type 2 diabetes,
Caffeine2
2
a systematic collection of the previous scientific papers on humanb. Food and food groupstudies, and its efficient application are essential. This study, therefore,
Grain
3
3
employed the systematic review to collect and evaluate the articles
Whole grain
43
systematically, where the inclusion criteria were developed to avoid an
Coffee85biased collection of relevant articles. The systematic review is very
Promoting factor
useful, because a review article enables us to objectively understand thea. Nutrient
concerned field to some extent, though its usefulness is not yet wellacknowledged in Japan.
Trans fatty acid4
2
The present systematic review revealed that the available cohort studies
Heme iron22
on the association between dietary factors and type 2 diabetes were
Glycemic index
32quite limited. While it can be pointed that some nutrients/foods are
Glycemic load
42
associated with the development of diabetes, its scientific evidence isb. Food and food groupstill insufficient. In addition, all 15 studies reviewed in this paper were
Processed meat2
2
conducted in Western countries; thus, it is important to examine dietaryfactors in relation to type 2 diabetes among Japanese populations.

Effect of dietary factors on incidence of type 2 diabetes: a systematic review of cohort studies.
Journal of Nutritional Science and Vitaminology. 2005;51: 292-310
Murakami K 1), Okubo H 2) and Sasaki S 2).
1) Department of Food and Nutritional Sciences, Graduate School of Nutritional and Environmental Sciences, University of
Shizuoka, Shizuoka, Japan
2) Project of Scientific Evaluation of Dietary Reference Intakes, National Institute of Health and Nutrition, Tokyo, Japan

Abstract: We systematically reviewed cohort studies on the effect of nutrient and food intake (except foralcohol) on the incidence of type 2 diabetes, which had been published in English as of May 2004. Using the
MEDLINE (PubMed) database as well as reference lists of searched papers, 15 individual cohort studies (a totalof 31 papers) were identified. The number of subjects (n= 895-85,060), follow-up length (5.9-23 y), the numberof diabetes cases (n= 74-4,085), dietary assessment method used (simple food questionnaire, food frequency
questionnaire, food frequency interview, diet history interview, and 24-h recall), and method of caseascertainment (questionnaire, oral glucose tolerance test, fasting glucose level, death certificate, and nationwide
registry) varied among studies. For nutrients, intakes of vegetable fat, polyunsaturated fatty acid, dietary fiber(particularly cereal fiber), magnesium, and caffeine were significantly inversely correlated and intakes of transfatty acid and heme-iron, glycemic index, and glycemic load were significantly positively correlated with theincidence of type 2 diabetes in several papers. For foods and food groups, several papers showed significantly
decreased risk for type 2 diabetes with the higher consumption of grain (particularly whole grain) and coffee, andsignificantly increased risk with processed meat consumption. Because all the studies were carried out inWestern countries, however, research in non-Western countries including Japan is needed.
6Latest Research
An association between Histidine intake and energy intake: a cross-sectional study inJapanese female students aged 18 years.
Hitomi Okubo, Satoshi Sasaki (Project of Scientific Evaluation of Dietary Reference Intakes)

Correlation Coefficient

Correlation Coefficient

Many people would like to know the answer of “What kind of foods should we take to suppress appetite, so that
we can lose weight?”. Well, histamine can be a candidate substance to suppress appetite. Recently, it has been
hypothesized that L-histidine (histidine), an essential amino acid, might also control food intake. Although theavailable evidence in animal studies strongly suggests the effect of histidine on food intake, few human studies
have been undertaken so far.
This study therefore examined the association between dietary histidine and energy intake among 1,689
Japanese female students aged 18 years, who entered dietetic courses in April 1997. Two questionnaires wereused in this study; one is a self-administered diet history questionnaire (DHQ) to assess dietary habits in theprevious one month, and the other is the questionnaire designed to assess the lifestyle variables. In order toassess the effects of daily histidine intake on energy intake, the multiple regression analysis was performed.
Here, we must be cautious that gender, body height, body weight and physical activity level could also affectenergy intake. In this analysis, therefore, we adjusted for these confounding factors, in order to examine theassociation between daily histidine intake and energy intake more precisely.
Firstly, a simple regression and correlation analysis was performed, which showed the positive correlation
between histidine intake and energy intake (Model 1, Figure A). Next, it was adjusted for non-dietary factors
such as body height, body weight, physical activity level, rate of eating, and this Model also showed the positive
correlation (Model 2, Figure A). However, after additional adjustment for dietary factors, such as total dietaryfiber and protein excluding histidine, histidine intake turned to show a negative correlation with energy intake(Model 3, Figure A). Similar trend was observed when histidine/protein ratio was used for the analysis, insteadof crude histidine intake (Figure B). In conclusion, our findings from a large and homogeneous sample
suggested that dietary histidine might have a suppressive effect on energy intake in human.
Yet, our message from
Figure. Association between histidine intake and energy intake
this study is that, rather
than the findings itself, the(A) Histigine(mg/d) and energy(MJ/d)(B) Histidine/protein(mg/d) and energy(MJ/d)effects of confounding
factors in human studies
are such a significant,enough to reverse theobserved results. This isbecause that, contrary to
animal studies, it is quite
Model1Model2Model1Model2difficult to undertake theModel3
human studies under the
Model3equal conditions. Future
epidemiologic studies with
better study designs are
Model1: Simple correlation. Model2: Correlation adjusted for body height, body weight, sports club activity, and rate ofwarranted to examine theeating. Model3: correlation additionally, adjusted for intake of dietary fiber and protein (excluding histidine for (A)).
role of dietary histidine inenergy intake in human.

Histidine intake may negatively correlate with energy intake in human: across-sectional study in Japanese female students aged 18 years.
Journal of Nutrition Science and Vitaminology. 2005;51:329-334
Okubo H and Sasaki S
Project of Scientific Evaluation of Dietary Reference Intakes, National Institute of Health and Nutrition, Tokyo, Japan.

Abstract: L-Histidine (histidine), a precursor of neuronal histamine, has recently been hypothesized tosuppress food intake. The association between dietary histidine and energy intake was examined among 1,689
Japanese female students of dietetic courses aged 18 y. Nutrient intakes were assessed over a 1-mo period witha validated, self-administered, diet history questionnaire. Both intake of histidine and the ratio of histidine toprotein (histidine/ protein) statistically and positively correlated with energy intake. After adjustment for potential
non-dietary confounding factors, including body height, body weight, physical activity level, and rate of eating,both the histidine intake and histidine/protein ratio statistically and positively correlated with energy intake(Pearson's correlation coefficient, r=0.62 and 0.12, respectively, p<0.001). Moreover, when protein or protein
excluding histidine was additionally included into the covariates in order to minimize the effect of dietary factors
and other amino acids, both histidine intake and histidine/protein ratio turned out to show a statistically negative
correlation with energy intake (r=-0.22 and -0.23, respectively, p<0.001). Considering the influence of
unavoidable various covariates, we found an inverse association between histidine/protein ratio and energy
intake among the young female Japanese students.
7

Latest Research
Puerariae radix prevents bone loss in castrated male mice
Yoshiko Ishimi (Division of Applied Food Research)
With advent of the aging society, the increased prevalence of osteoporosis became a significant public healthproblem. Osteoporosis is a skeletal disorder characterized by compromised bone strength, in terms of both bonemineral density and bone quality, which predisposes a person to the increased risk of fracture. It is reported thatabout half the Japanese women experience the bone fracture associated with osteoporosis in their lifetime.
Likewise, male also suffer from this disorder, due to the reduction of androgen secretion and aging. According toan epidemiological study, about 20% of males aged over 75 years develop osteoporosis. While the sex hormone
regulating bone turnover of adult males is mainly androgen, a recent study explored that estrogen also played
an important role in regulating the male skeleton. For example, men with genetic defect of estrogen receptor, as
well as those with defect of enzyme necessary to produce estrogen from androgen, would develop osteoporosis.
We have been working on the nutritional researches on the prevention of osteoporosis. In previous studies, wehave reported that soybeans isoflavones (genistein) prevented bone loss caused by androgen deficiency inmale osteoporotic animal models. Isoflavonoids are also included in Puerariae radix (PR) (its root is classified as“medicine” and its seeds, leaves, flower and kudzu starch are classified as “food”). Isoflavone content in PR was
10mg/g, five times as high as the one in soybeans. In Japan, PR is commonly taken as herbal medicine to treat
the common cold etc., though little is known about the effects on bone. In this study, therefore, we investigatedthe effects of PR on the bone metabolism in osteoporotic model mice, and the results of male mice are as below;
Firstly, male mice were orchidectomized (ORX) and fed a diet containing 5% to 20% of PR for 4 weeks, after
which bone mineral density (BMD) of femurs were analyzed by DXA. The whole femoral BMD was significantly
lower in ORX mice, though its decrease in BMD was completely prevented by intake of the diet with 5% PR. It isnotable that the BMD in the PR group was obviously higher compared with the sham-operated group, and thisvalue was the same level as in the E2 group. When the site-specific effect of PR was examined, the effect wasmost strongly observed in the distal region, which consists of trabecular bone (Figure). On the other hand, there
was no significant effect on the bodyweight or on other organs. In
Total Femur
Distal Femur
conclusion, this study explored thatthe intake of PR would prevent boneloss in ORX mice. Now, we expectthat you could consider your own
bone health and the prevention of
osteoporosis,
when
you
take
kudzu-mochi (a kind of Japanese
sweets made of kudzu) or kudzu-yu(hot drink with kudzu powder).
Please contact us if you would like tohave the information on the above
patent application.

Puerariae radix prevents bone loss in castrated male mice.
Metabolism, 2005; 54:1536-1541
Wang X, Wu J, Chiba H, Yamada K and Ishimi Y.
Division of Applied Food Research, National Institute of Health and Nutrition, Tokyo, Japan

Abstract: Puerariae radix (PR) is one of the earliest and most important crude herbs used in Chinese medicine
for various medicinal purposes. PR contains a high amount of isoflavonoids, such as daidzein and genistein,which are known to prevent bone loss induced by estrogen deficiency. We have demonstrated that PR not only
completely prevents bone loss but also significantly increases the bone mass at high doses in ovariectomized
mice without exhibiting estrogenic action in the uterus. In this study, we examined whether PR exhibits effects onbone loss in androgen-deficient male mice similar to estrogen-deficient female mice. Male mice wereorchidectomized (ORX) and fed a diet containing low, middle, and high doses (5%, 10%, and 20% of diet,respectively) of PR or normal diet with subcutaneous administration of 17beta-estradiol (E(2), 0.03 microg/d;Sigma, St Louis, Mo), for 4 weeks. In ORX mice, the seminal vesicle weight decreased markedly, and it was notaffected by the administration of any doses of PR and E(2). The bone mineral density (BMD) of the whole femur
was significantly decreased by ORX, and the decrease in BMD was completely prevented by intake of the dietwith the low dose of PR. Intake of the diet with the middle dose of PR further normalized BMD in ORX mice.
Furthermore, the high dose of PR administration (PR20) significantly increased BMD in ORX mice, and thepotency was similar to that of E(2). Morphometric analysis of the femoral metaphysis showed that intake of thediet with the low dose of PR completely prevented the decrease in bone volume/tissue volume and trabecularnumber and restored the increase in trabecular separation in ORX mice. In addition, intake of the diet with thehigh dose of PR further increased bone volume/tissue volume and trabecular number and decreased trabecularseparation in ORX mice. These results propose the possibility that estrogenic Chinese herbs such as PR can beone of the candidates for the treatment or prevention of osteoporosis in elderly men with hypogonadism.
8