Effectiveness of diet versus exercise intervention on weight reduction in local Japanese residents
Environ Health Prev Med
Effectiveness of diet versus exercise intervention on weight reduction in local Japanese residents
Chihiro Toji 0 1 2 3 4 5 6
Naoko Okamoto 0 1 2 3 4 5 6
Tomomi Kobayashi 0 1 2 3 4 5 6
Yoko Furukawa 0 1 2 3 4 5 6
Sanae Tanaka 0 1 2 3 4 5 6
Kayoko Ueji 0 1 2 3 4 5 6
Mitsuru Fukui 0 1 2 3 4 5 6
Chigusa Date 0 1 2 3 4 5 6
0 N. Okamoto Department of Nutrition, Faculty of Wellness, Shigakkan University , 55 Nadakayama Yokone-cho, Ohbu, Aichi 474-8561 , Japan
1 C. Toji T. Kobayashi S. Tanaka Human Environmental Sciences, Department of Food Science and Nutrition, Mukogawa Women's University , 6-46 Ikebiraki-cho, Nishinomiya, Hyogo 663-8558 , Japan
2 C. Toji (&) Department of Food and Nutritional Sciences, School of Natural Science and Ecological Awareness, Graduate School of Humanities and Sciences, Nara Women's University , Kitauoya-nishimachi, Nara 630-8506 , Japan
3 C. Date Department of Food Science and Nutrition, School of Human Science and Environment, University of Hyogo , 1-1-12 Shinzaike-Honcho, Himeji, Hyogo 670-0092 , Japan
4 M. Fukui Laboratory of Statistics, School of Medicine, Osaka City University , 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585 , Japan
5 K. Ueji Department of Health and Nutrition, Faculty of Health Science, Kio University , 4-2-2 Umami-naka Koryo-cho, Kitakatsuragi-gun, Nara 635-0832 , Japan
6 Y. Furukawa Department of Health and Nutrition, Faculty of Health Science, Kyoto Koka Women's University , 38 Kadono-Cho Nishikyougoku, Ukyo-ku, Kyoto 615-0882 , Japan
Objective To evaluate the effect of diet versus exercise intervention on weight reduction. Methods Participants were randomly divided by gender, age, and living area into four groups: group DE (diet and exercise, n = 16), group D (diet only, n = 15), group E (exercise only, n = 15), and group C (control, n = 16). This study ultimately aimed to help participants reduce their body mass index (BMI) by 7% of baseline value. Subjects were 62 residents (men and women ranging in age from 40 to 69 years) of two residential areas in Nara Prefecture, Japan, who participated in annual health checkups in 2006. BMI of the participants was C24 and \28 kg/m2 at baseline examination. All participants agreed to undergo a 6-month intervention between January 2007 and September 2007.
Diet and exercise education; Diet only education; Exercise only education; Weight reduction; Japanese residents
The 2006 National Health and Nutrition Survey conducted
in Japan showed that 1 out of every 2 men and 5 women
aged between 40 and 74 years were strongly suspected to
be either experiencing or at the risk of developing
metabolic syndrome [
]. Obesity is an important contributing
factor of metabolic syndrome, and preventive measures are
needed to counteract it. Studies conducted in China,
Australia, Holland, Finland, and the USA have shown that
incidence of diabetes may be lessened or prevented
altogether by weight reduction through diet and exercise
], and meta-analysis was performed to
confirm the weight-reducing effect , with results
suggesting that significant weight reduction could be attained
with combined education about diet and exercise.
Although body mass index (BMI) of Asians is lower
compared with Europeans and Americans, Asians are more
likely to develop abdominal obesity, type 2 diabetes
mellitus, and high blood pressure [
]. However, to date, few
reports in Japan have examined the effectiveness of diet and
exercise education on weight reduction among
neighborhood residents with an established control group [
In Japan, no research team has made comparative
studies of effective weight loss intervention methods, such
as with differing educational methods. These intervention
procedures include combined education of diet and
exercise, diet education alone, and exercise education alone.
Here, we investigated the effect of combined diet and
exercise education on achieving weight loss among local
Japanese residents with BMI between 24 and 28 kg/m2
with an established control group.
Materials and methods
Cases and samples
Our study was conducted among residents of Kashiba City and
Kammaki Town in Nara Prefecture, two residential areas near
major cities. The subjects were men and women aged from 40
to 69 years who had received an annual health checkup in 2006
and whose BMI was from 24 to 28 kg/m2. They confirmed
during an oral consultation that they had no history of
treatment, nor were they currently being treated for diabetes, heart
disease, or stroke. A total of 896 residents satisfied the above
conditions (701 city residents and 195 town residents). We sent
them a letter requesting their participation in our intervention
study targeted at weight loss. Details were explained at an
explanatory meeting, after which 80 residents agreed to give
their written informed consent to participate (62 city residents
and 18 town residents). However, two residents subsequently
declined participation, leaving 78 residents enrolled at baseline
examination. A further 15 were excluded later for failing to
meet the eligibility criteria at baseline examination, and a
further 1 declined participation. This study ultimately enrolled
62 subjects (47 city residents and 15 town residents). The flow
of participants through the trial is shown in Fig. 1.
Study subjects were divided into four groups after stratified
random allocation by area of residence, sex, and age. The
combined diet and exercise education group (group DE)
included 16 participants, the diet education-only group
(group D) included 15 participants, the exercise
educationonly group (group E) included 15 participants, and the
control group (group C) included 16 participants.
We set a 6-month intervention period. During this period,
groups DE, D, and E received intervention after baseline
examination, whereas participants in group C managed
their weight on their own, with no intervention. Group C
received health leaflets through the mail once a month (five
times total). However, the leaflets were not related to weight
loss, but rather concerned other health-related matters such
as influenza, vegetable selection, ultraviolet (UV) radiation,
and preventing food poisoning and heart attacks.
A final examination measuring the same parameters
assessed at baseline was conducted 6 months after baseline
examination. The effects of intervention were assessed by
examining the difference in measurements taken at
baseline and final examinations.
This study was conducted from January 2007 to July
2007 in Kashiba City and from March 2007 to September
2007 in Kammaki Town, Nara Prefecture, Japan.
The goal for participants assigned to receive intensive
lifestyle intervention was to achieve and maintain weight
reduction of at least 7% of initial BMI. The target weight
reduction over 6 months was set at 7% of BMI at baseline
examination, with target monthly weight reduction of
1–2 kg. Given these values, we approximated the energy
which should be reduced per day to be 1046–2094 kJ. In
group DE, we split this energy reduction into two parts:
intake energy and expended energy. Specifically, we
instructed the subjects to decrease their daily intake energy
by 523–1046 kJ, and increase their daily energy
expenditure by 523–1046 kJ through walking exercises. Group D
was instructed to decrease their daily energy intake by
1046–2094 kJ, while group E was instructed to increase
daily energy expenditure by 1046–2094 kJ through
walking exercises. Registered dietitians (RDs) and health fitness
programmers (HFPs) issued instructions seven times: four
Subjects were male and female residents of Kashiba City and Kammaki Town in
Nara Prefecture aged 40-69 years who participated in annual health check-ups in
2006 and had a BMI 24 kg/m2 but <28 kg/m2. Subjects who had undergone or
were currently undergoing treatment for diabetes mellitus or heart disease were
Attended the explanatory meeting and
gave informed written consent (n=80)
Baseline examination (n=78)
Study participants (n=62)
Diet + Exercise education
times in the first half of the 6-month intervention period,
and once a month in the second half.
The duration of 2 h per contact session was set for each
of group DE, group D, and group E; more specifically,
group DE received 2 h of diet- and exercise-related
education (1 h each), while group D received 2 h of diet
education and group E received 2 h of exercise education.
With regard to diet education, RDs initially spoke with
each subject in groups DE and D individually, thereafter
giving lectures to the groups as a whole. Meal
improvement targets were set for each subject by the RD during the
first contact session. These targets were determined by the
RD after consulting with the subject and were aimed at
resolving problems in dietary intake which the RDs
informed them of based on the results of a food frequency
questionnaire (FFQ). The FFQ was administered before the
Final examination (at 6 months)
intervention, and the RDs described the subject’s dietary
pattern using the Japanese Food Guide Spinning Top [
The subjects kept a weight diary which was used as a
teaching material. During the individual session at the first
meeting, the subject recorded meal targets; they were
instructed to mark an ‘‘s’’ for any achieved targets and an
‘‘9’’ otherwise. Daily weight measurements were also
recorded in the diary.
RDs conducted group education by giving lectures on
‘‘balanced diet,’’ ‘‘relationship between diet and obesity,’’
‘‘how to include vegetables in the diet,’’ ‘‘how to eat
between meals,’’ and ‘‘sugar and salt.’’
With regard to the target of the exercise group, ‘‘the target
number of walking steps to be increased’’ was set by the
RDs. This number was meant to be the target which each
subject deemed achievable, judging from the number of
walking steps recorded at baseline examination. The HFPs
were in charge of group exercise education and gave
specific instructions regarding walking, stretching, and
myodynamic resistance exercises. The subjects kept a weight
and walking steps diary to be used as a teaching material.
They entered in the diary their exercise targets set during
their individual session and marked an ‘‘s’’ if the target
was achieved and an ‘‘9’’ if it was not. They also recorded
their daily weight measurements and the number of steps
walked as measured by a pedometer (Digi-Walker; Yamasa
Tokeikeiki Co. Ltd., Tokyo, Japan).
Anthropometric measurements consisted of weight, height,
and abdominal circumference. Weight was measured in
100-g units, and height in millimeters. BMI was calculated
by the following formula: BMI = weight (kg)/height (m)2.
Measurements were taken by staff who had received
sufficient training in measuring abdominal circumference
based on the method used in the Physical Condition
Assessment of the National Health and Nutrition
Examination Survey (conducted by the National Institute of
Health and Nutrition of Japan). They measured each
subject’s abdominal circumference to the nearest 0.5 cm at the
level of the navel with the subject in standing position.
Biochemical blood parameters used as evaluation
indices were blood glucose, hemoglobin A1c (HbA1c),
albumin/globulin (A/G) ratio, total cholesterol, high-density
lipoprotein (HDL) cholesterol, and triglycerides.
Approximately 12 ml blood was collected from an antecubital vein
at least 5 h after a meal.
Blood pressure was measured twice, with the subject in
seated position, using a blood pressure monitor (HM-701;
ELK Corporation, Osaka, Japan). The mean of the two
values was used for analysis.
Habitual energy and nutrient intake were estimated
using the self-administered FFQ developed by Date et al.,
which includes 76 food items. The subjects recorded their
intake amount and frequency for each item over the
previous 1-year period. To estimate the portion size for each
item, we used a life-size color food photograph collection
prepared specifically for use in the FFQ. Energy and
nutrient intake per day were computed using original
software based on the Standard Tables of Food
Composition in Japan (5th revised and enlarged edition).
Biochemical blood analyses were conducted by Japan
Medical Laboratory Co. Ltd., Osaka, Japan.
National Health and Nutrition Examination Survey conducted
in Japan [
], we estimated the mean baseline BMI to be
25.5 kg/m2. We assumed the drop in BMI after at least one
type of intervention to be an average of 7% (BMI decrease of
1.8 kg/m2, standard deviation 1.5 kg/m2). We also assumed
no change in the control group, which did not receive any
education at all. The study was designed to have 80% power to
detect a 1.8 kg/m2 difference in BMI over 6 months. Values
were considered statistically significant for p \ 0.05, and a
15% dropout rate was assumed. These assumptions
necessitated enrollment of at least 15 subjects per group.
Stratified randomization was carried out at Nara Women’s
University. The primary analysis was conducted by applying
intention-to-treat methods, with baseline values carried
forward for missing values. A paired t test was used to measure the
effect of 6 months’ intervention on anthropometric
measurements, physiological measurements, results of blood chemistry
tests, dietary intake, and the number of steps walked per day
within each group. One-way factorial analysis of variance
(ANOVA) was performed to compare groups at baseline and
after intervention for variables of interest. If significant
differences were noted, intervention groups were compared with
the control group (as a reference group) using Dunnett’s
multiple comparison test. Differences between groups in
baseline values were assessed by analysis of variance.
SPSS (17.0) statistical analysis software (SPSS Inc.,
Chicago, IL, USA) was used in the present study. Values
were considered statistically significant at p \ 0.05, and
two-sided significance levels are quoted.
Our study plan was reviewed and approved by the Research
Ethics Screening Committee of Nara Women’s University.
All enrolled subjects gave their written informed consent.
The subjects were assured that they were free to
discontinue participation at any point if they so wished, even if they
had already consented to participate in the study. Data were
made anonymous to protect subjects’ personal privacy.
During the 6 months following the final examination,
group C received diet education to provide them with an
opportunity to reduce their weight, but a new control group
was not established, and thus we did not take into
consideration the effect of intervention on group C.
The end point for this study was BMI value after 6-month
intervention. Referring to the BMI distribution obtained in the
DE diet ? exercise, D diet, E exercise, C control, SD standard deviation
* One-way factorial ANOVA was performed to compare the four groups
a Calculated as weight in kilograms divided by the square of the height in meters
E (n = 15)
groups. With regard to analysis of variance, no significant
difference between the groups was observed. With regard
to subject participation, 89% of the subjects who
underwent the baseline examination participated in the final
Changes in BMI at final examination compared with
baseline are presented in Fig. 2 and Table 2. Mean change
in BMI from baseline to final examination was as follows:
group DE mean BMI decreased from 25.7 to 24.0 kg/m2
(-6.6%), group D mean BMI decreased from 25.4 to
24.1 kg/m2 (-5.3%), group E mean BMI decreased from
25.5 to 24.9 kg/m2 (-2.3%), and group C mean BMI
decreased from 25.8 to 24.8 kg/m2 (-2.2%). In all groups,
the reduction in BMI from baseline to final examination
was significant (DE, p \ 0.001; D, p \ 0.001; E,
p = 0.009; C, p = 0.019). Taking into account group C’s
2.2% reduction in BMI, the net weight loss effects of the
intervention were 4.3% for group DE, 3.1% for group D,
and 0.1% for group E. Comparing the decrease in BMI, the
decreases observed in groups DE and D were
significantly greater than that in group C (DE, p = 0.002; D,
p = 0.041). However, the decrease in BMI observed in
group E was not significant compared with that in group C
(p = 1.000).
Mean values and standard deviations for anthropometric
measurements physiological measurements, blood
chemical tests, dietary intake, and number of steps walked per
day at baseline and final examination for each group are
presented in Table 2. Mean change in body weight from
baseline to final examination was as follows: group DE
mean body weight decreased from 61.5 to 57.4 kg
(-4.1 kg), group D mean body weight decreased from 62.4
to 58.9 kg (-3.5 kg), group E mean body weight
decreased from 62.4 to 61.0 kg (-1.4 kg), and group C
mean body weight decreased from 61.9 to 60.4 kg
(-1.5 kg). Reduction in body weight from baseline to final
examination was significant in all groups (DE, p \ 0.001;
D, p \ 0.001; E, p = 0.010; C, p = 0.027; data not shown
in table). Significant decrease was observed in all groups
for mean abdominal circumference value at final
examination compared with that at baseline. Systolic blood
pressure values fell significantly in groups DE and D, but
diastolic blood pressure values were significantly decreased
only in group D. With regard to blood chemical tests,
blood glucose values were significantly reduced only in
group DE (mean decrease 0.19 mmol/l). HbA1c increased
significantly in group C. With regard to A/G ratio, no
significant drop was observed in any group. Serum total
cholesterol was significantly reduced only in group D
(mean decrease 0.3 mmol/l), while HDL cholesterol fell
significantly only in groups DE and C. Serum triglyceride
levels were significantly increased in group C.
DE diet ? exercise, D diet, E exercise, C control, SD standard deviation
Baseline, baseline examination; Final, final examination (at 6 months); Blood glucose, 5-h glucose; A/G ratio, albumin/globulin
* Within-group changes from baseline, significance of paired t test
One-way factorial ANOVA and Dunnett’s multiple comparison test were performed to compare the four groups
Significant difference between diet ? exercise and exercise (unpaired t test)
a Control different from diet ? exercise (p \ 0.05)
b Control different from diet (p \ 0.05)
c Control different from exercise (p \ 0.05)
Comparing mean values for energy, protein, and
carbohydrate intake at final examination with those at baseline
in each group, a significant decrease was observed only in
group D. However, no significant decrease in fat intake
was observed in any group. Comparing mean values for
number of walking steps at final examination with that at
baseline for groups DE and E, both groups showed a
significant increase (mean increase 1559 steps for group DE
and 3714 steps for group E).
In the present study, we examined the effect of lifestyle
improvement on weight reduction among local residents of
one city and one town in Nara Prefecture, Japan. After
6 months of intervention the mean BMI change was
-6.6% among those receiving diet and exercise education,
-5.3% in those receiving only diet education, -2.3% in
those receiving only exercise education, and -2.2% in
those in the control group. In comparison of the control
group with the intervention groups, significant weight loss
was observed in the diet and exercise education group
(p = 0.002) and in the diet-only group (p = 0.041).
Multi-institutional research regarding whether diet or
exercise education can better prevent occurrence of
diabetes has been performed on glucose-tolerance-impaired
patients or impaired glycemia patients in China [
], Holland [
], Finland [
], and the USA .
Research conducted in the USA found that diabetes
prevention was more effectively achieved by reduction of
caloric intake and increase of energy expenditure than by
drugs, highlighting the importance of lifestyle
improvement in preventing onset of diabetes.
However, comparisons between Japan and the
abovementioned countries has shown stark differences with
regard to eating habits, overall physique, and race make-up,
among other such characteristics, and for this reason we
cannot easily deliver the same diet and exercise education
to Japanese people as to peoples of other countries.
Lifestyle improvement techniques adapted specifically to Japan
are necessary. Combined education on diet and exercise
has been suggested to be effective in preventing obesity
], and several randomized clinical trials (RCTs)
have compared the effectiveness of combined education
with education on diet or exercise alone [
most of these studies lacked a control group and therefore
were unable to provide sufficient proof of effectiveness.
Few studies in Japan have scientifically demonstrated by
comparison with a control group the effect of diet
education and exercise education on weight reduction targeting
local residents judged to have BMI slightly higher than
normal or to be slightly obese. In 2007–2008, Tanaka et al.
investigated the effectiveness of intervention in improving
metabolic syndrome and visceral fat [
they failed to establish control groups. We established
control groups and investigated the effect of intervention
by comparing the effects of combined education on diet
and exercise with effects of diet or exercise education only,
thereby offering new information.
Persons with BMI C24 but \28 kg/m2 were chosen as
subjects in the present study. Given that persons with
weights falling in the upper end of the normal range were
anticipated to be at high risk of becoming obese, we chose
those with BMI C24 kg/m2 as subjects. While the World
Health Organization (WHO) criterion for obesity is BMI
C30 kg/m2, the proportion of individuals with BMI
C30 kg/m2 is lower in Japan than in Western countries. As
no persons in the local area had BMI C28 kg/m2, we instead
chose subjects with BMI \28 kg/m2 for the present study.
Given that a number of studies have reported a possible
6-month BMI of between 3% and 10%, we set a target BMI
decrease of 7% by 6 months after baseline examination
]. In study by the Diabetes Prevention
Program Research Group as well, weight loss of 7% was
]. In the present study, 44% (n = 7/16) of subjects
in group DE, 27% (n = 4/15) in group D, 13% (n = 2/15)
in group E, and 13% (n = 2/16) in group C experienced
BMI decrease of 7% or more. The education given to the
study participants also suggested that, in addition to body
weight, abdominal circumference may be reduced.
With regard to blood test values such as blood glucose,
no significant change was seen in comparison of the
intervention groups with the control group. Given that the blood
glucose level of those in the intervention group was already
relatively low before the start of the study, their blood
glucose levels may not have been able to fall any further.
Further, given that the evaluation criteria assessed in the
present study were derived from pre-existing BMI, blood
pressure, and hematological data, no new findings were
feasible. However, given the present paucity of studies in
Japan assessing diet and exercise depletion, we believe the
results of this present study conducted in Japan to be of
We need to look at the results of this study with a little
reservation for the following reasons. First, this study was
targeted at local residents living in the suburbs, mainly
women. We therefore cannot be sure whether the same
results may be obtained among urban residents. Second,
although we invited 896 residents with BMI between 24 and
28 kg/m2 to participate in the study by posted mail, only 62
of them were ultimately enrolled. It is likely that they may
have been particularly eager to receive education and
improve their lifestyle. Third, exercise habits were evaluated
by change in the number of walked steps. The reason we
adopted walking in our exercise education is that this was a
physical activity which subjects could accomplish every day
with reasonable safety and without any special equipment or
the aid of trainers. Only groups DE and E were fitted with
pedometers, and therefore the change in the number of steps
for groups D and C was not analyzed. If the level of physical
activity had been analyzed using a structured questionnaire,
results may have been easier to interpret. Fourth, to evaluate
the quantity of energy intake, the FFQ was conducted in all
subjects in this study, and their response to it might have
raised their awareness of their poor dietary habits without
diet education. After the intervention period, based on the
results of the FFQ, we advised the subjects without diet
education, though comments both oral and written, regarding
how to change their diet contents.
The number of walked steps significantly increased among
participants who received exercise education. However,
because they did not receive any diet education, no significant
change occurred in their diet intake. Overall, group E subjects
had higher numbers of steps walked but a lower proportion of
members achieving the target step numbers than in group DE.
This seemed to be the reason why group E failed to burn the
target calorie amount through walking. In addition, group E,
which received no diet education, exhibited no beneficial
effects from walking on weight reduction, in contrast to
group DE, which did receive diet education.
Intervention with both diet and exercise education
appears to be incorporated more easily and routinely
among subjects and is believed to motivate the subjects
more than intervention with either alone. We therefore
believed that group E would show similar change in BMI
to the control group.
Results from the present study showed that
exerciseonly education was not effective in achieving weight
reduction, at least among a group of Japanese adults with
BMI [24 and B28 kg/m2 whose average age was 62 years.
Whether the same results may be found among the younger
generation or those with higher BMIs, or among other
racial groups, remains unclear.
Acknowledgments This work was supported by a Research Fund
for Health Science from the Ministry of Health, Labor, and Welfare in
Japan. The authors express their thanks to the Public Health Bureaus
of Kashiba City and Kammaki Town for their cooperation. The
authors also thank Ms Hiromi Shinno (HFP), Ms Yuriko Kawaguchi
(HFP), and Ms Hideko Shinohara (RD) for their cooperation.
Conflict of interest The authors declare they have no conflict of
1. Office for Life-Style Related Diseases Control General Affairs Division Health Service Bureau Ministry of Health, Labour and Welfare . The National Health and Nutrition Survey in Japan 2006 . Tokyo: Dai-ichi Shuppan; 2009 . p. 77 - 8 (in Japanese).
2. Pan XR , Li GW , Hu YH , Wang JX , Yang WY , An ZX , et al. Effects of diet and exercise in preventing NIDDM in people with impaired glucose tolerance . The Da Qing IGT and Diabetes Study. Diabetes Care . 1997 ; 20 : 537 - 44 .
3. Dunstan DW , Zimmet PZ , Welborn TA , Cameron AJ , Shaw J , de Courten M , et al. The Australian Diabetes, Obesity and Lifestyle Study (AusDiab)-methods and response rates . Diabetes Res Clin Pract . 2002 ; 57 : 119 - 29 .
4. Mensink M , Corpeleijn E , Feskens EJ , Kruijshoop M , Saris WH , de Bruin TW , et al. Study on lifestyle intervention and impaired glucose tolerance Maastricht (SLIM): design and screening results . Diabetes Res Clin Pract . 2003 ; 61 : 49 - 58 .
5. Tuomilehto J , Lindstro¨m J , Eriksson JG , Valle TT , Ha¨ma¨la¨inen H, Ilanne-Parikka P , et al. Prevention of type 2 diabetes mellitus by changes in lifestyle among subjects with impaired glucose tolerance . N Engl J Med . 2001 ; 344 : 1343 - 50 .
6. Lindstro¨ m J , Louheranta A , Mannelin M , Rastas M , Salminen V , Eriksson J , et al. The Finnish diabetes prevention study (DPS): lifestyle intervention and 3-year results on diet and physical activity . Diabetes Care . 2003 ; 26 : 3230 - 6 .
7. Knowler WC , Barrett-Connor E , Fowler SE , Hamman RF , Lachin JM , Walker EA , et al. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin . N Engl J Med . 2002 ; 346 : 393 - 403 .
8. Franz MJ , Van Wormer JJ , Crain AL , Boucher JL , Histon T , Caplan W , et al. Weight-loss outcomes: a systematic review and meta-analysis of weight-loss clinical trials with a minimum 1-year follow-up . JADA . 2007 ; 107 : 1755 - 67 .
9. James WP . The epidemiology of obesity: the size of the problem . J Intern Med . 2008 ; 263 : 336 - 52 .
10. Ishida S , Ito C , Murakami F , Horikawa C , Gennai N , Katayama M , et al. Prevention of type 2 diabetes mellitus by changing lifestyles among high risk persons: the diabetes prevention program of Hiroshima (DPPH). Design and one-year interim report on feasibility . J Jpn Diabetes Soc . 2004 ; 47 : 707 - 13 (in Japanese).
11. Murakami F , Ito C , Ishida S . Prevention of type 2 diabetes mellitus by changing lifestyles among high risk persons . J Soc Met Clin Nutr . 2004 ; 7 : 27 - 34 (in Japanese).
12. Sakane N , Sato J , Tsushita K , Tsujii S , Kotani K , Tsuzaki K , et al. Prevention of type 2 diabetes in a primary healthcare setting: three-year results of lifestyle intervention in Japanese subjects with impaired glucose tolerance . BMC Public Health . 2011 ; 17 : 11 - 40 .
13. Sasai H , Katayama Y , Numao S , Nakata Y , Tanaka K. Effects of exercise on visceral fat in obese middle-aged men: comparison to dietary modification . Jpn. J. Phys. Fitness Sports Med . 2008 ; 57 : 89 - 100 (in Japanese).
14. Okura T , Nakata Y , Ohkawara K , Numao S , Katayama Y , Matsuo T , et al. Effects of aerobic exercise on metabolic syndrome improvement in response to weight reduction . Obesity . 2007 ; 15 : 2478 - 84 .
15. Takemi Y , Yoshiike N , editors. The Japanese food guide spinning top ''manual'' . Tokyo: Dai-ichi Shuppan Publishers; 2005 (in Japanese).
16. Office for Life-Style Related Diseases Control General Affairs Division Health Service Bureau Ministry of Health, Labour and Welfare. The National Health and Nutrition Survey in Japan . Tokyo: Dai-ichi Shuppan Publishers; 2006 . p. 147 - 8 (in Japanese).
17. Carels RA , Darby L , Cacciapaglia HM , Douglass OM , Harper J , Kaplar ME , et al. Applying a stepped-care approach to the treatment of obesity . J Psychosom Res . 2005 ; 59 : 375 - 83 .
18. Koebnick C , Plank-Habibi S , Wirsam B , Gruendel S , Hahn A , Meyer-Kleine C , et al. Double-blind, randomized feedback control fails to improve the hypocholesterolemic effect of a plantbased low-fat diet in patients with moderately elevated total cholesterol levels . Eur J Clin Nutr . 2004 ; 58 : 1402 - 9 .
19. Cox KL , Burke V , Morton AR , Beilin LJ , Puddey IB . The independent and combined effects of 16 weeks of vigorous exercise and energy restriction on body mass and composition in free-living overweight men-a randomized controlled trial . Metabolism . 2003 ; 52 : 107 - 15 .
20. Mensink M , Feskens EJ , Saris WH , De Bruin TW , Blaak EE . Study on lifestyle intervention and impaired glucose tolerance Maastricht (SLIM): preliminary results after one year . Int J Obes . 2003 ; 27 : 377 - 84 .
21. Delahanty LM , Hayden D , Ammerman A , Nathan DM . Medical nutrition therapy for hypercholesterolemia positively affects patient satisfaction and quality of life outcomes . Ann Behav Med . 2002 ; 24 : 269 - 78 .
22. Liao D , Asberry PJ , Shofer JB , Callahan H , Matthys C , Boyko EJ , et al. Improvement of BMI, body composition, and body fat distribution with lifestyle modification in Japanese Americans with impaired glucose tolerance . Diabetes Care . 2002 ; 25 : 1504 - 10 .
23. Thomson RL , Buckley JD , Lim SS , Noakes M , Clifton PM , Norman RJ . Lifestyle management improves quality of life and depression in overweight and obese women with polycystic ovary syndrome . Fertil Steril . 2010 ; 94 : 1812 - 6 .
24. Christiansen T , Paulsen SK , Bruun JM , Pedersen SB , Richelsen B . Exercise training versus diet-induced weight-loss on metabolic risk factors and inflammatory markers in obese subjects: a 12-week randomized intervention study . Am J Physiol Endocrinol Metab . 2010 ; 298 : E824 - 31 .
25. Molenaar EA , van Ameijden EJ , Vergouwe Y , Grobbee DE , Numans ME . Effect of nutritional counselling and nutritional plus exercise counselling in overweight adults: a randomized trial in multidisciplinary primary care practice . Fam Pract . 2010 ; 27 : 143 - 50 .
26. Coker RH , Williams RH , Yeo SE , Kortebein PM , Bodenner DL , Kern PA , et al. The impact of exercise training compared to caloric restriction on hepatic and peripheral insulin resistance in obesity . J Clin Endocrinol Metab . 2009 ; 94 : 4258 - 66 .
27. Christiansen T , Paulsen SK , Bruun JM , Overgaard K , Ringgaard S , Pedersen SB , et al. Comparable reduction of the visceral adipose tissue depot after a diet-induced weight loss with or without aerobic exercise in obese subjects: a 12-week randomized intervention study . Eur J Endocrinol . 2009 ; 160 : 759 - 67 .
28. Volpe SL , Kobusingye H , Bailur S , Stanek E . Effect of diet and exercise on body composition, energy intake and leptin levels in overweight women and men . J Am Coll Nutr . 2008 ; 27 : 195 - 208 .
29. Anderssen SA , Carroll S , Urdal P , Holme I. Combined diet and exercise intervention reverses the metabolic syndrome in middleaged males: results from the Oslo Diet and Exercise Study . Scand J Med Sci Sports . 2007 ; 17 : 687 - 95 .
30. Cook NR , Kumanyika SK , Cutler JA , Whelton PK . Doseresponse of sodium excretion and blood pressure change among overweight, nonhypertensive adults in a 3-year diet intervention study . J Hum Hypertens . 2005 ; 19 : 47 - 54 .
31. Kennedy BM , Paeratakul S , Champagne CM , Ryan DH , Harsha DW , McGee B , et al. A pilot church-based weight loss program for African-American adults using church members as health educators: a comparison of individual and group intervention . Ethn Dis . 2005 ; 15 : 373 - 8 .
32. Waller SM , Vander Wal JS , Klurfeld DM , McBurney MI , Cho S , Bijlani S , et al. Evening ready-to-eat cereal consumption contributes to weight management . J Am Coll Nutr . 2004 ; 23 : 316 - 21 .
33. Burke V , Giangiulio N , Gillam HF , Beilin LJ , Houghton S. Physical activity and nutrition programs for couples: a randomized controlled trial . J Clin Epidemiol . 2003 ; 56 : 421 - 32 .
34. Xiao Y , Zhang ZT , Wang JB , Zhu WL , Zhao Y , Yan SF , et al. Effects of diet intervention on hyperlipidemia in eight communities of Beijing, China . Biomed Environ Sci . 2003 ; 16 : 112 - 8 .
35. James AP , Watts GF , Barrett PH , Smith D , Pal S , Chan DC , et al. Effect of weight loss on postprandial lipemia and low-density lipoprotein receptor binding in overweight men . Metabolism . 2003 ; 52 : 136 - 41 .
36. Lantz H , Peltonen M , Torogerson LJ . A Diet and behavioral programme for the treatment of obesity. A 4-year clinical trial and a long-term post treatment follow-up . J Intern Med . 2003 ; 254 : 272 - 9 .
37. Lindstrom J , Eriksson JG , Valle TT , Aunola S , Cepaitis Z , Hakumaki M , et al. Prevention of diabetes mellitus in subjects with impaired glucose tolerance in the Finnish diabetes prevention study: results from a randomized clinical trial . J Am Soc Nephrol . 2003 ; 14 : S108 - 13 .
38. McManus K , Antinoro L , Sacks F. A randomized controlled trial of a moderate-fat, low-energy diet compared with a low fat, lowenergy diet for weight loss in overweight adults . Int J Obes . 2001 ; 25 : 1503 - 11 .
39. Ramirez EM , Rosen JC . A comparison of weight control and weight control ? body image therapy for obese men and women . J Consult Clin Psychol . 2001 ; 69 : 440 - 6 .
40. Dzator JA , Hendrie D , Burke V , Gianguilio N , Gillam HF , Beilin LJ , Houghton S. A randomized trial of interactive group sessions achieved greater improvements in nutrition and physical activity at a tiny increase in cost . J Clin Epidemiol . 2004 ; 57 : 610 - 9 .