Obese Japanese Adults Research Articles

Relationship of work-related and leisure-based screen time with obesity: a cross-sectional study on adults including older adults.

The relationship between screen time (ST) and obesity has been demonstrated; however, few studies have differentiated between work-related and leisure-based use in Japanese adults, including older adults. This study aimed to examine the relationship between both work-related and leisure-based ST and obesity in adults. This cross-sectional study was based on a questionnaire survey conducted in 2018. Overall, 9947 adults were invited; 3161 participants (31.8%) returned the questionnaire. Finally, 2488 participants (597 younger men (YM), 792 younger women (YW), 542 older men (OM), 557 older women (OW)) were included. The main exposures were work-related, leisure-based, and total ST. The outcome was obesity (body mass index ≥ 25 kg/m2). Log-binomial regression analysis was used to calculate prevalence ratios (PRs) and confidence intervals (CIs) for obesity with 1-h increments of each ST. Analyses were conducted in all participants and subgroups comprising YM, YW, OM, and OW. Total ST was significantly associated with obesity in all participants (PR (95% CI) 1.07 (1.04-1.10), YM (1.05 (1.01-1.10)), OM (1.13 (1.05-1.22)), and OW (1.13 (1.02-1.26)). Work-related ST was significantly associated with obesity in all participants (1.08 (1.04-1.12)), YM (1.06 (1.00-1.12)), and OM (1.24 (1.08-1.42)). Leisure-based ST was significantly associated with obesity in all participants (1.09 (1.04-1.14)), YM (1.09 (1.00-1.18)), and YW (1.10 (1.01-1.20)). ST is associated with obesity in Japanese adults including older adults; particularly, work-related ST is associated with obesity in men, and leisure-based ST, in younger individuals.

Effect of Intake of Bifidobacteria and Dietary Fiber on Resting Energy Expenditure: A Randomized, Placebo-Controlled, Double-Blind, Parallel-Group Comparison Study.

Bifidobacterium animalis subsp. lactis GCL2505 in combination with inulin has been shown to have several health benefits, including an improvement in the intestinal microbiota and a reduction in human visceral fat. Previous studies have suggested that the visceral fat reduction of GCL2505 and inulin may be achieved by improving daily energy expenditure. This parallel, placebo-controlled, randomized, double-blind study was conducted to evaluate the effects of GCL2505 and inulin on resting energy expenditure (REE) in overweight or mildly obese Japanese adults (n = 44). Participants ingested 1 × 1010 colony forming units of GCL2505 and 5.0 g of inulin daily for 4 weeks. REE score at week 4 was set as the primary endpoint. At week 4, the REE score of the GCL2505 and inulin group was significantly higher than that of the placebo group, with a difference of 84.4 kcal/day. In addition, fecal bifidobacteria counts were significantly increased in the GCL2505 and inulin group. Our results indicated that the intake of GCL2505 and inulin improves energy balance, which is known to be a major factor of obesity, by modulating the microbiota in the gut. This is the first report to demonstrate the effects of probiotics and dietary fiber on REE in humans.

Effects of substituting sedentary time with physical activity on body mass index in Japanese adults with Down syndrome: A cross-sectional study

Objectiveand Rationale: Obesity is a health challenge for adults with Down syndrome. Therefore, a physical activity promotion program is required to prevent or reduce obesity in adults with this condition. However, there is a lack of evidence of useful risk reduction initiatives. The objective of this study was to suggest a rationale for behaviors that should replace time of inactivity to reduce obesity in Japanese adults with Down syndrome. MethodsThe participants were adults with Down syndrome, aged 18–48 years, living in Japan. The snowball sampling method was used. To detect an effect size of 0.20 for body mass index using an F-test, 80 participants were required, generating a statistical power of 0.8 and a risk level of 0.05. Survey items included sex, age, height, weight, body mass index, and physical activity (min/d). Physical activity was categorized by intensity and further divided into ambulatory and non-ambulatory activities. The body mass index categories were compared using analysis of covariance. An isotemporal substitution model was used to confirm the interdependence of behaviors. ResultsHalf of the participants were obese, with a body mass index of 25 kg/m2 or higher. The obese group had significantly fewer light physical activity, moderate-to-vigorous physical activity, and ambulatory moderate-to-vigorous physical activity times than the non-obese group. Replacing 10 min of sedentary behavior with ambulatory moderate-to-vigorous physical activity was significantly associated with a lower body mass index. ConclusionsThis study suggests a rationale for behaviors that should replace time of inactivity to reduce obesity in adults with Down syndrome. Specifically, replacing 10 min of sedentary behavior with ambulatory moderate-to-vigorous physical activity time may contribute to obesity reduction.

Coffee and metabolic phenotypes: A cross-sectional analysis of the Japan multi-institutional collaborative cohort (J-MICC) study

Background and aimsTo date, the relationship between coffee consumption and metabolic phenotypes has hardly been investigated and remains controversial. Therefore, the aim of this cross-sectional study is to examine the associations between coffee consumption and metabolic phenotypes in a Japanese population. Methods and resultsWe analyzed the data of 26,363 subjects (aged 35–69 years) in the baseline survey of the Japan Multi-Institutional Collaborative Cohort Study. Coffee consumption was assessed using a questionnaire. Metabolic Syndrome (MetS) was defined according to the Joint Interim Statement Criteria of 2009, using body mass index (BMI) instead of waist circumference. Subjects stratified by the presence or absence of obesity (normal weight: BMI <25 kg/m2; obesity: BMI ≥25 kg/m2) were classified by the number of MetS components (metabolically healthy: no components; metabolically unhealthy: one or more components) other than BMI.In multiple logistic regression analyses adjusted for sex, age, and other potential confounders, high coffee consumption (≥3 cups/day) was associated with a lower prevalence of MetS and metabolically unhealthy phenotypes both in normal weight (OR 0.83, 95% CI 0.76–0.90) and obese subjects (OR 0.83, 95% CI 0.69–0.99). Filtered/instant coffee consumption was inversely associated with the prevalence of MetS and metabolically unhealthy phenotypes, whereas canned/bottled/packed coffee consumption was not. ConclusionThe present results suggest that high coffee consumption, particularly filtered/instant coffee, is inversely associated with the prevalence of metabolically unhealthy phenotypes in both normal weight and obese Japanese adults.

Effects of paramylon-rich Euglena gracilisEOD-1 powder on visceral fat obesity in moderately obese Japanese adults: A randomized, double-blind, placebo-controlled, parallel-group trial.

To investigate whether supplementation of paramylon (PM)-rich Euglena gracilis EOD-1 powder (EOD-1) reduces visceral fat obesity in moderately obese Japanese subjects. A randomized, double-blind, placebo-controlled intervention study was conducted involving 36 Japanese adults with a body mass index (BMI) ≥25 and <30 kg/m2. Subjects were randomly assigned into two groups to consume EOD-1 capsules (EOD-1 group, 2.6g PM/day) or cellulose capsules (placebo group) for a 12-week period. Anthropometric measurements including visceral fat area (VFA) and blood samples were measured at baseline and throughout the trial. There was no significant difference in VFA between the two groups, although subgroup analysis by gender showed a significant decrease in VFA in the male EOD-1 group compared with the placebo group. Serum adiponectin levels in all subjects from the EOD-1 group were significantly higher than in the placebo group. By comparison with the placebo group, the subjects in the EOD-1 group showed a significant reduction in serum HbA1c levels. EOD-1 intake led to a significant reduction in VFA in male subjects with moderate obesity (BMI 25-30 kg/m2). PM in EOD-1 may contribute to preventing visceral fat obesity in male Japanese subjects. Moreover, PM may also contribute to improving glucose homeostasis in moderately obese Japanese adults.

The effect of age on the association between daily gait speed and abdominal obesity in Japanese adults

The aim of this work was to investigate the effect of age on the association between daily gait speed (DGS) and abdominal obesity defined by visceral fat area (VFA). A cross-sectional study was performed using data from an annual community-based health check-up. A total of 699 participants aged 20–88 years were enrolled in this analysis. DGS was assessed using tri-axial accelerometers worn for ≥ 7 days with at least 10 measuring hours each day. VFA was measured using a visceral fat meter. Since DGS differed significantly with age, the participants were divided into two groups: younger adults (YA), aged 20–49 years, and older adults (OA), aged 50–88 years. The association between DGS and VFA differed significantly with age (r = 0.099 for YA and r = − 0.080 for OA; test for difference between correlation coefficients, P = 0.023). In OA, the adjusted odds ratio of abdominal obesity (VFA ≥ 100 cm2) was 0.40 (95% confidence interval 0.18, 0.88, P = 0.022) for the highest DGS quartile (DGS ≥ 1.37 m/s) compared to that for the lowest quartile (DGS < 1.11 m/s), whereas no significant association was found in YA. These data could aid in raising awareness of the self-management of obesity via DGS monitoring, especially in OA.

Weight loss reduces the incidence of dipstick proteinuria: a cohort study from the Japanese general population.

Though elimination of obesity is one of main therapeutic goal for lifestyle-related diseases, the impact of appropriate weight loss on reduction of the incidence of proteinuria in the general population is still unclear. The study cohort was based on a general population of 9,33,490 from 40 to 74years of age who had undergone annual specific health checkups. The subjects who were finally included were the 2,74,598 people for whom all the data necessary for this study were available. The incidence of proteinuria in this study was defined as negative proteinuria at the primary and secondary survey years, and newly developed proteinuria during subsequent follow-up years. Whereas people with rapidly decreased weight tended to have a high incidence of proteinuria in the underweight (BMI < 18.5kg/m2) and normal weight (18.5-24.9kg/m2) groups, the obese group (≥ 25.0kg/m2) with rapidly decreased weight had a lower incidence compared to those with stable weight. In the obese population, a rapid decline of BMI (-1 to -5kg/m2 per year) was associated with a reduced risk (hazard ratio [95% confidence interval]; 0.89 [0.80-0.98], P = 0.02) of proteinuria. Weight reduction can lead to a risk reduction of 11% in the incidence of proteinuria in obese Japanese adults. This is the first study to report the effects of weight reduction on the early phase of chronic kidney disease in obesity relevant to the characteristics of the Japanese general population. The present findings might have a role in renal health promotion in Japan.

Trends in Energy Imbalance Gap and Body Weight Status in the Japanese Adult Population: A System Dynamics Approach.

BackgroundThe double burden of malnutrition is a growing public health problem in Japan. We estimated the dynamics of the energy imbalance gap (EIG) (average daily difference between energy intake and expenditure) to explain trends in the prevalence of underweight, overweight, and obese Japanese adults.MethodsWe used individual-level data on body height and weight from the National Health and Nutrition Surveys from 1975 to 2015. We calibrated a validated system dynamics model to estimate the EIG for Japanese adults aged 20 to 74 years by survey year, sex, and weight status classified by the body mass index (BMI).ResultsThe overall EIG for men increased from 2.3 kcal/day in 1975 to 4.7 kcal/day in 1987 and then decreased to 2.3 kcal/day in 2015. The overall EIG for women consistently decreased from 4.3 kcal/day in 1975 to −0.5 kcal/day in 2015. By BMI class, the EIG for men with a BMI of <30 kg/m2 began to decrease around 1990, indicating a deceleration in the prevalence of overweight and obese men. The EIG consistently decreased for women with a BMI of <25 kg/m2 and reached negative values from the late 2000s to early 2010s, indicating a gradual decrease in the prevalence of overweight and obese women.ConclusionsThe dynamics of the EIG were different across sex and weight groups. Public health interventions should target a further decrease in the EIG for normal-weight, overweight, and obese men and a stop in the decreasing trends of the EIG in underweight and normal-weight women.

768-P: Efficacy and Safety of Low-Carb Diet of 50g/Day and 120g/Day in Obese Patients

Objective: Nutrition therapy is indispensable in the management of obesity. Low-carb diet is one of the recommended diets. On the other hand, there is little evidence on Low-carb diet in Japan. Besides, we don’t know the optimum amount of carbohydrate. So, we tried to ellucidate the efficacy and safeness of Low-carb diet, and to compare two amounts of Low-carb diet: 50g (LC50g) or 120g carb/day (LC120g). Research Design and Methods: 42 Overweight or obese Japanese adults with one or more metabolic disorders (such as diabetes, hyperlipidemia, hypertension) were randomly assigned to a 3-month Low-Carb diet intervension (50g or 120g carb/day). All food was provided, and patients were assigned to report what they ate every day to the registered dietitian via mail, so that we could check compliance. Total calorie was calculated based on the ideal body weight and physical activity index. Every month, body weight, body composition (measured by multi-frequency BIA) were checked. Blood pressure, HbA1c, FPG, serum ketone body, kidney and liver function and lipid profile, serum C-peptide, urinary albumin, PWV/ABI were checked. We used T test for statistic analysis. Results: No one dropped out. Median age and BMI were 43 and 28.5. Change in BW was -8.5kg in LC50g, -7.2kg in LC120g, there was no significant difference. AST, ALT, γGTP, LDH, Cre decreased after intervention in both groups. LDH, Cre significantly decreased in LC50g. Acetoacetic acid and EPA significantly increased in LC50g. Baseline analysis showed, BW at age 20, early rising, dinner time and exercise habits were related to susceptibility to losing weight. A questionnaires survey revealed patients felt more stressful in LC50g. Conclusion: In this study, both amount of carb restriction was effective and safe, and there was no significant difference in losing weight, diabetes, lipid and hypertension control. LC120g was easy to carry out. Finally, this study is the one and only because it achieved high compliance by food offering and on time follow-up. Disclosure T. Kikuchi: None.

Professional dietary coaching within a group chat using a smartphone application for weight loss: a randomized controlled trial.

PurposeTo test the effectiveness of professional dietary coaching via group chat using a smartphone application (app) for weight loss.MethodsThis study was a 12-week, assessor-blind, parallel-group, waitlist-controlled randomized trial that included a 4-week follow-up period (trial registration, UMIN000025340). Data were collected between October 2016 and May 2017 and were analyzed between July 2017 and January 2018. Participants were 112 overweight, obese, or abdominally obese Japanese adults, aged 20 to 64 years, with at least one cardiometabolic risk factor. Participants were randomized to the coaching group (n=75) or control group (n=37), with a ratio of 2:1. The coaching group received a commercial weight loss program characterizing dietary coaching by a certified nutrition professional via group chat delivered on a smartphone app. Participants posted photos of every meal into the group chat, and the certified professional gave immediate direct feedback and encouragement. The primary outcome was an 8-week weight change. Secondary outcomes included 8-week changes in cardiometabolic risk factors. The frequency of meal photo uploads was recorded as a measure of adherence.ResultsOf the 112 randomized participants, 93 (83.0%) and 81 (72.3%) completed 8-week and 12-week visits, respectively. Intention-to-treat analysis demonstrated significantly larger 8-week weight loss in the coaching group (−1.4 kg; 95% confidence interval [CI]: −2.0, −0.8 kg) than that in the control group (−0.1 kg; 95% CI: −0.6, 0.4 kg). Significantly larger improvements in triglyceride and glycated hemoglobin A1c levels were also obtained in the coaching group. These benefits, except for the triglyceride level, were maintained until week 12. The frequent upload of meal photos was associated with a larger 8-week weight loss in a dose–response fashion (P-value for trend <0.001).ConclusionThis smartphone-delivered commercial weight loss program characterized as dietary coaching via group chat resulted in modest but significant weight loss. Facilitating participants’ active involvement in the program is necessary to achieve greater health benefits.

Does Weight Reduction Affect Foot Structure and the Strength of the Muscles That Move the Ankle in Obese Japanese Adults?

Obesity is considered a major influential factor of foot structure and function. It has been reported to result in detrimental alterations of foot structure indicators and a decrease in muscle strength, which can lower the quality of life and increase the morbidity of obesity. The purpose of the present study was to determine the effect of weight reduction on foot structure and the strength of the muscles that move the ankle in obese adults. A total of 33 obese Japanese participants (mean body mass index 28.49 ± 2.87 kg/m2) without an exercise habit participated in a 12-week dietary modification program. Their foot structure indicators were measured using a 3-dimensional foot scanner, and the strength of the muscles that move the ankle was assessed using a dynamometer. After the dietary modification, the mean body weight reduction was 7.49 ± 4.10 kg (9.38%; 77.82 ± 13.26 kg before and 70.33 ± 11.37 kg after; p < .001). The wide foot indicators, including the forefoot girth, rearfoot width, and instep girth, had decreased significantly (p < .05), and the decreases correlated positively with the weight reduction. Regarding the strength of the muscles that move the ankle, except for dorsiflexion, all the measured peak torque values per body weight had increased significantly (p < .01). These results suggest that the weight reduction induced by a 12-week dietary modification results in thinner feet and increased strength of the muscles that move the ankle.

Reduction of HbA1c levels by fucoxanthin-enriched akamoku oil possibly involves the thrifty allele of uncoupling protein 1 (UCP1): a randomised controlled trial in normal-weight and obese Japanese adults.

Lifestyle-related problems are becoming a major health threat in East Asian countries. Therefore, finding an efficacious nutraceutical for this population is important. One candidate is fucoxanthin (Fx), a carotenoid abundantly found in edible brown seaweed that has been associated with a number of valuable health-promoting benefits. Unfortunately, clinical studies of Fx are limited. In the present study, we aimed to evaluate the effects of Fx on obesity-related parameters in Japanese subjects harbouring an SNP associated with lifestyle-related problems. In all, sixty normal-weight and obese Japanese adults with BMI over 22kg/m2 were single-blinded and randomly assigned to three Fx-dose cohorts and administered Fx-enriched akamoku oil containing Fx at 0, 1 or 2mg/d for 8 weeks (n 20 per group). Parameters relating to obesity and serum Fx metabolites were measured before and after intervention, but no significant differences were observed between and within the groups. Despite no changes in visceral fat areas and resting energy expenditures after intervention, we observed a significant decline in HbA1c levels in the 2mg/d Fx group compared with that in the 0mg/d group (P<0·05), which was correlated with an increase in serum fucoxanthinol (Fx metabolite) levels. In addition, HbA1c levels declined more significantly in subjects with G/G alleles of the uncoupling protein 1 (UCP1) gene than in those with the A/A and A/G alleles (P<0·05). We conclude that although Fx supplementation does not affect visceral fat areas, it may reduce HbA1c levels in those harbouring the thrifty allele of UCP1-3826A/G.

Effect of Bifidobacterium animalis ssp. lactis GCL2505 on visceral fat accumulation in healthy Japanese adults: a randomized controlled trial.

Bifidobacterium animalis ssp. lactis GCL2505 (B. lactis GCL2505) is able to survive passage through the intestine and then proliferate, leading to an increase in the amount of gut bifidobacteria. In the present study, we evaluated the impact of B. lactis GCL2505 on abdominal visceral fat storage in overweight and mildly obese Japanese adults. This clinical study was a double-blind, randomized, placebo-controlled, parallel-group comparative trial performed for 12 weeks. Healthy Japanese subjects (N=137) with body mass indices ranging from 23 to 30 kg/m2 consumed either fermented milk containing B. lactis GCL2505 or a placebo every day, and then visceral and subcutaneous abdominal fat areas were measured by computed tomography as the primary endpoints. The number of fecal bifidobacteria was also measured. Visceral fat area, but not subcutaneous fat area, was significantly reduced from baseline at 8 and 12 weeks in the GCL2505 group, compared with the placebo group. The total number of fecal bifidobacteria was significantly increased in the GCL2505 group. These results indicate that B. lactis GCL2505 reduces abdominal visceral fat, a key factor associated with metabolic disorders. This finding suggests that this probiotic strain can potentially serve as a specific functional food to achieve visceral fat reduction in overweight or mildly obese individuals.

Independent association of liver fat accumulation with insulin resistance

To examine the association of intrahepatic fat with homeostasis model assessment-insulin resistance (HOMA-IR), a marker of insulin resistance, in Japanese adults, and whether intrahepatic fat is associated with insulin resistance independent of waist circumference and other measures of obesity. Fifty-three individuals aged 37-69 were studied. Spectrum obtained using a 3-T magnetic resonance imager was analysed with LCModel to quantify intrahepatic fat. Blood levels of insulin, glucose and other biochemical markers were obtained after 8h or more fasting. Percent body fat was estimated by a bioelectrical impedance analyzer. HOMA-IR and intrahepatic fat content were log-transformed in the analysis. We found a positive correlation between intrahepatic fat and HOMA-IR, which was independent of the anthropometric measures of obesity. In contrast, significant and positive correlations of body mass index, percent body fat, and waist circumference with HOMA-IR were largely explained by their associations with intrahepatic fat. Intrahepatic fat was positively associated with alanine transaminase and triglycerides even after adjustment for HOMA-IR. Intrahepatic fat was associated with insulin resistance independent of age, sex, and measures of obesity in Japanese adults. Hypertriglyceridemia and liver injury may directly occur subsequent to intrahepatic fat accumulation.

Effect of a dietary supplement containing kurozu (a Japanese traditional health drink) concentrate on several obesity-related parameters in obese Japanese adults: a randomized, double-blind, placebo-controlled trial

Objective: This study was undertaken to examine the Kurozu concentrate (KC) based dietary supplement on several obesity-related parameters in obese Japanese male and female adults.Background: Kurozu, which is a specific type of rice vinegar produced by fermentation of unpolished brown rice, has long been used as a traditional health food and folk medicine in Japan. A recent animal study and our preliminary human study suggest that the KC supplement has potential for use in the management of obesity.Materials and Methods: A 12-week, randomized, double-blind, placebo-controlled trial was conducted involving 48 Japanese adult subjects (28 males and 20 females) with obesity. Subjects were either assigned to the group consuming the KC supplement for 12 weeks (870mg/day; 480 mg/day as KC) (n=24; 14 males and 10 females) or the placebo group (n=24; 14 males and 10 females). All test participants were assessed using several obesity-related parameters, including body weight, BMI, waist circumference, and abdominal fat computed tomography (CT) sections. These measurements took place at baseline and at week 12. Results: At week 12, a significant decrease in body weight (P&lt;0.043) and nearly significant decreased values of BMI (P=0.052) were observed in the KC group compared to the placebo group. The reduction in waist circumference at week 12 within the KC group was not significantly greater than the placebo group. Examination of abdominal CT sections around the navel indicated that, although most of the values of the total fat area, subcutaneous fat area, and visceral fat area for both of the placebo and KC groups significantly increased during the 12-week intervention, the magnitude of increase in the total fat area for all subjects and that of the total fat area, subcutaneous fat area, and visceral fat area for females on one or more of three CT sections were significantly lower in the KC group than the placebo group (P&lt;0.05).Conclusion: Although the results are not definitive, KC supplementation may have potential for improving some obesity-related parameters in obese subjects, particularly females.Key words: Kurozu concentrate (KC), KC-based dietary supplement (KC supplement), abdominal obesity-related parameters, body mass index (BMI), computed tomography (CT), abdominal fat

Reduced masticatory function in non-elderly obese Japanese adults

Abnormal eating behaviors such as compulsive overeating, eating fast, chewing less, palatable soft food preferences and avoiding hard food are often observed in obese individuals, and these behaviors may affect their masticatory function, but little information of masticatory function in obese subjects are available at present. The present study investigated masticatory function in non-elderly obese Japanese adults and explored the relationships between obesity and masticatory function. Seventy-five obese subjects (BMI ≥ 25; male: 34, female: 41) and 98 subjects with normal weight (BMI 18.5-25; male: 63, female: 35) aged 25-40 years old were enrolled in the present study. The status of masticatory function was determined using a chewing gum mixing method, a direct method of examining masticatory function, and the numbers of present teeth, untreated decayed teeth, missing teeth, and filled teeth were also examined. Masticatory function was significantly lower in the obese subjects both in male and female, whereas the numbers of present teeth, decayed teeth, missing teeth and filled teeth did not differ significantly between the obese subjects and the controls both in male and female. Multiple regression analysis revealed a significant correlation between obesity and reduced masticatory function after adjustment for gender, age, and numbers of decayed teeth, missing teeth, and filled teeth. Significantly reduced masticatory function was found in male and female non-elderly obese adults based on direct measurement of masticatory function. Multiple regression analysis suggested that obesity might induce reduced masticatory function.

Obese Japanese Adults with Type 2 Diabetes Have Higher Basal Metabolic Rates than Non-Diabetic Adults

Several cross-sectional studies in Pima Indians and Caucasians have indicated that obese individuals with type 2 diabetes have a higher basal metabolic rate (BMR) than healthy, obese individuals. However, no study has investigated this comparison in Japanese subjects, who are known to be susceptible to type 2 diabetes due to genetic characteristics. Thirty obese Japanese adults with pre-type 2 diabetes (n=7) or type 2 diabetes (n=13) or without diabetes (n=10) participated in this study. BMR was measured using indirect calorimetry. The relationships between residual BMR (calculated as measured BMR minus BMR adjusted for fat-free mass, fat mass, age, and sex) and biomarkers including fasting glucose, glycosylated hemoglobin (HbA(1c)), fasting insulin, homeostasis model assessment of insulin resistance (HOMA-R), triglycerides, and free fatty acids were examined using Pearson's correlation. BMR in diabetic subjects adjusted for fat-free mass, fat mass, age, and sex was 7.1% higher than in non-diabetic subjects. BMR in diabetic subjects was also significantly (p<0.05) higher than in non-diabetic subjects. There was a significant correlation between residual BMR and fasting glucose (r=0.391, p=0.032). These results indicate that in the Japanese population, obese subjects with type 2 diabetes have higher BMR compared with obese non-diabetic subjects. The fasting glucose level may contribute to these differences.

High prevalence of periodontitis in non-elderly obese Japanese adults

Several recent reports have indicated a high prevalence of periodontitis in obese subjects, but the results have not been consistent. This study was performed to investigate the prevalence of periodontitis in non-elderly obese Japanese adults and to explore the relationship between obesity and periodontitis. Ninety-five obese subjects (BMI ≥ 25; males: 44, females: 51) and 102 subjects with normal weight (BMI 18.5-25; males: 66, females: 36) were enrolled from April 1997 to March 1999 in the study. All subjects were aged 25-40 years old. The status of periodontitis was evaluated based on the intraoral community periodontal index (CPI) codes of the WHO, and the numbers of present teeth, untreated decayed teeth, missing teeth, and filled teeth were also examined. The prevalence of periodontitis was significantly higher in obese subjects, and particularly in females, compared to controls, whereas the numbers of present teeth, decayed teeth, missing teeth and filled teeth did not differ significantly between the obese subjects and the controls for both males and females. Multiple logistic regression analysis revealed that obesity was significantly related to periodontitis. A high prevalence of periodontitis was found in non-elderly Japanese obese subjects, and particularly in obese female adults. Correlation analysis also suggested that obesity carries a high risk for development of periodontitis.

Nonlinear relationships between visceral fat area and percent regional fat mass in the trunk and the lower limbs in Japanese adults

The present study aimed to examine the relationship between visceral fat area (VFA) and regional fat mass (RFM) or its distribution characteristics and to compare these characteristics between normal and visceral obesity Japanese adults. Nonobese and nonvisceral obese Japanese adults (control group (CG): 44 men and 47 women), obese but nonvisceral obese (obesity group (OG): 15 men and 21 women) and visceral obese group (VOG, 80 men and 17 women). Obesity and visceral obesity were defined as body mass index > or = 25 kg m(-2) and VFA > or = 100 cm(2), respectively, based on the criteria of the examination committee of criteria for obesity disease in Japan. RFM of the both arms, trunk and both legs were measured by DEXA, and we calculated the percent RFM (%RFM). The VFA and subcutaneous fat area were measured at the umbilicus level using CT scans. We examined the relationship between VFA and RFM or %RFM in the Japanese adult population. Although linear relationships were found between VFA and each RFM, nonlinear relationships were found between VFA and each %RFM. In CG, %RFM of the trunk increases and %RFM of the leg decreases with accumulating VFA, but these relationships declined in VOG. These results may suggest that the relationship between %RFM and VFA changes between different visceral obese levels, and for Japanese adults this is found at reaching a 100 cm(2) VFA, which corresponds to the criteria for visceral obesity.

Segmental Body Composition Assessment for Obese Japanese Adults by Single-Frequency Bioelectrical Impedance Analysis with 8-point Contact Electrodes

This study aimed to determine the accuracy of segmental body composition variables estimated by single-frequency BIA with 8-point contact electrodes (SF-BIA8), compared with dual-energy X-ray absorptiometry (DXA). Subjects were 72 obese Japanese adults (43 males and 29 females) aged 30 to 66 years. Segmental body composition variables (fat free mass: FFM, fat mass: FM, and percent fat mass: %FAT) were measured by these techniques. The correlations between impedance values and FFM measured by DXA were calculated. To examine the consistency in predicted values (SF-BIA8) with the reference (DXA), significant mean differences were tested by t-test and the degree of the difference was assessed by effect size. Correlations between the reference and predicted values were calculated. Additionally, the standard error of estimation (SEE) when estimating the reference from the predictor and the relative value of the SEE to the mean value of the DXA measurement (%SEE) were calculated. Systematic error was examined by Bland-Altman plots. High correlations were found between impedance and FFM measured by SF-BIA8. FFM in the extremities showed high correlations with the reference values, but systematic error was found. SF-BIA8 tended to overestimate FFM in the trunk. The consistencies in %FAT and FM with the reference value are inferior to those for FFM, and SEE values in %FAT and FM were greater than those for FFM. The accuracy of the estimated values in the trunk (FFM, %FAT, and FM) are inferior to those of the total body and extremities.