Onion peel extract reduces the percentage of body fat in overweight and obese subjects: a 12-week, randomized, double-blind, placebo-controlled study

BACKGROUND/OBJECTIVES: The anti-obesity effect of quercetin-rich onion peel extract (OPE) was suggested in rats, but information from human studies is limited. This study aimed to investigate the effects of OPE on the body composition of overweight and obese subjects. MATERIALS/METHODS: In this 12-week, randomized, double-blind, placebo-controlled study, parallel clinical trials were performed in overweight and obese Korean subjects. Randomly assigned subjects were instructed to take daily either the placebo (male, 6 and female, 30) or OPE capsules containing 100 mg of quercetin (male, 5 and female, 31). Body composition was measured by using bioimpedance and dual-energy X-ray absorptiometry (DXA). Resting energy expenditure (REE) and respiratory quotient (RQ) were evaluated by using indirect calorie measurement methods. Fasting blood levels of glucose, insulin, lipids, and leptin were determined. RESULTS: Quercetin-rich OPE supplementation significantly reduced the weight and percentage of body fat as measured by DXA (P = 0.02). These effects were not shown in the control group. Levels of blood glucose (P = 0.04) and leptin (P = 0.001 for placebo, P = 0.002 for OPE) decreased in both groups. Significant increases in REE and RQ were observed in both groups (P = 0.003 for placebo, P = 0.006 for OPE) and in the OPE group alone (P = 0.02), respectively. CONCLUSIONS: Quercetin-rich OPE supplementation changed the body composition of the overweight and obese subjects. This result suggests a beneficial role of the anti-obesity effect of OPE human subjects.

Validity of simple, novel measures of generalized and central obesity among young Asian Indian women.

Objective: The study examined the validity of simple and novel measures of generalized obesity- [body mass index (BMI, kg/m 2 ), fat mass index (FMI, kg/m 2 ), and body fat percent (BF%)] and central obesity- [waist circumference (WC, cm), waist-hip ratio (WHR), and waist-to-height ratio (WC/ht ratio)] against BF% and BMI as criteria. It also aimed to predict fat-free mass index (FFMI, kg/m 2 ), FMI, and BF% ranges for various BMI categories. Design: Cross-sectional study. Materials and Methods: Weight, BF%, fat mass (FM), and fat-free mass (FFM) were measured using leg-to-leg bioelectrical impedance in 183 women. Height, hip, and waist circumferences were taken using standard methods. The indices [FMI, FFMI, WHR, W/ht ratio] were computed. Results: The study revealed that FMI, BMI, WC, and WC/ht ratio were highly correlated with BF% (r = 0.978; r = 0.939; r = 0.894; r = 0.890, respectively, P < 0.01), whereas WHR had the least correlation (r = 0.497, P < 0.01). The FMI showed a higher positive predictive value (PPV) in diagnosing generalized obesity compared to BMI with BF% as criterion and higher PPV than BF% with BMI as criterion. Considering only the indices of central obesity, WC was the most predictive in identifying women with high BF% (≥30% and ≥35%), whereas WC/ht ratio proved to be a better index in identifying women with BMI greater than 23 and 25 kg/m 2 . The normal BMI for Asians (18.5-23 kg/m 2 ), the at-risk group (23- 25 kg/m 2 ), and the obese class I (25-30 kg/m 2 ) corresponded to FFMI values of 14.1-15.1 kg/m 2 , 15.1-15.5 kg/m 2 , 15.5-16.1 kg/m 2 , respectively, and to FMI values of 4.4-7.9 kg/m 2 , 7.9-9.5 kg/m 2 , 9.5-13.9 kg/m 2 , respectively. The BMI cutoff of 18.5, 23, 25, 27.5, and 30 kg/m 2 corresponded to BF% of 23.6, 34.3, 38.3, 42.6, and 46.3%, respectively. Conclusion: FMI was a better predictor of generalized obesity compared to BMI and BF%. Considering abdominal obesity as an independent risk factor for insulin resistance, both WC and WC/ht ratio were able to predict central obesity better than WHR. Finally, the study presents ranges for FFMI and FMI for various BMI categories.

Factors Related to Increase of Blood Pressure in Obese Children and Adolescents

Background: As obese population is increasing nowadays, research on blood pressure of obese children is being performed more frequently. However, there are only few research related to factors about blood pressure among obese children in Korea. The purpose of this study was to analyze the factors affecting blood pressure of obese children and adolescents. Methods: The subjects were elementary and middle school students diagnosed with obesity (n=1716). Height, weight, waist circumstance, body fat percent, blood pressure were measured. Family history and sexual maturity were investigated through the questionnaire. The relationship between the factors and the increase of blood pressure was analyzed. Results: Body weight was the most powerful factor among to factors related to increase of blood pressure (male r=0.45, P<0.05, female r=0.37, P<0.05). Also, height, percentage weight for height (PWH), body mass index (BMI) and waist circumference was correlated with the blood pressure. In multiple regression analysis, family history of hypertension and the sexual maturity were significant determinants of blood pressure in males after adjusting for weight. However, body fat percent was a significant determinant in females. Conclusion: Body weight was the most important factor which increased the blood pressure in obese children and adolescents in both sexes. But males and females had different factors related to the increase of blood pressure with the exception of body weight.

Distribution and Correlates of Obesity in a Korean Rural People / 한국역학회지

OBJECTIVE: The aim of present study was to assess the distribution and correlates of obesity in a Korean rural people using both body mass index(BMI) and body fat percent. METHODS: A total of 1,243 participants were recruited using a two-staged stratified sampling. A structured questionnaire was used to ask their sociodemographics (gender, age, marital status, educational background, and etc.) and health-related behaviors (smoking, drinking, and regular exercise etc.). The data of weight-for height, and body fat percent were also collected by physical examination. For the estimation and analysis of correlates of obesity, we used BMI(>or=25kg/m2) and body fat percent(male>or=25%, female>or=30) as a cut-point of obesity. All analyses were stratified to three age groups(>20, 20-39, 40>or=). RESULTS: The prevalence of obesity in this study was higher than that in previous studies. This study showed that 32.6% (male: 33.7%, female: 31.7%) of participants according to BMI, and 45.6% (male: 43.8%, female: 47.4%) of them according to body fat percent were obese group. Logistic regression analysis showed that, in the criteria of BMI, while obesity was associated with female and low educational background under the age of 40, prevalence of obesity was higher in non smokers over the age of 40. In case of body fat percent crteria, single(unmarried, divorced, separated, widowed) were more likely to be obese in male aged 20 to 39 years. In the group aged 40 years and over, risk of obesity was higher in female than in male. CONCLUSION: This result suggests that obesity is common in Korean rural areas, especially among adolescents and female aged 40 years or over, and the risk factors for obesity were different by age. It is required that health management program focusing on obesity and its adverse outcomes should be developed in a community setting.

Correlation between Body Fat Percent Estimated by Bioelectrical Impedance Analysis and Other Variable Methods

PURPOSE: Obesity is a significant health problem with medical and psychological consequences for children and adolescents. The purpose of this study was to assess the correlation between body fat percent using bioelectrical impedance(BI) and other variable methods. METHODS: We measured height, weight, body mass index(BMI) and body fat percent by skinfold thickness(ST) and BI in 1,035(496 male; 539 female) children from seven to 18 years of age. The correlation coefficients between BI and each of the other different methods were obtained. The sensitivity and specificity to predict obesity by these several methods were studied. RESULTS: Fat percent estimated by BI analysis and BMI showed a strong correlation(r=0.749). Fat percent estimated by BI analysis and ST showed a very strong correlation(r=0.835). At the 95th percentile cut-off point for BI, ST showed a sensitivity of 57.7%, and a specificity of 97.6% for estimating body fat. At the 95th percentile cut-off point for BI, BMI showed a sensitivity of 84.9%, and a specificity of 99.3% for estimating body fat. CONCLUSION: The fat percent estimated by BI analysis correlated strongly with ST or BMI. BI analysis is an objective and accurate method for estimating body fat in childhood obesity.

Associations between asthma and anthropometric indices in korean adults / 천식및알레르기

BACKGROUND: Obesity is related to asthma symptoms and air way hyperresponsiveness. Both asthma and obesity are becoming worldwide chronic health problems. This study was designed to evaluate the association between asthma and anthropometric indices such as body mass index (TMI), body fat percent, and waist-hip ratio (WHR) in Korean adults. METHODS: Three thousand twenty-four subjects aged. 20-79 years, were enrolled in the survey during April - December, 2001. A standardized questionnaire was used to collect general information and asthma symptoms. Obesity was defined as BMI > or =25kg/m2. Over body fat and central obesity was defined as more than 75th percentile of body fat percent and WHR, respectively. RESULTS: The prevalence of asthma in korean adults was 29.6%(male 29.9% and female 29.33%). Asthma was significantly higher in elderly age (> or = 50 years), cigarette smokers. alcohol drinkers. patients with a family history of parent's asthma, and obesity. After adjusting for possible confounders. BMI [OR=1.33 (1.12-1.59)], over body fat [OR=1.28(10.7-1.54)] and central obesity [OR=1.41(1.17-1.70)] remained significant predictors of asthma. CONCLUSION: Our results showed that general obesity and central obesity are potential risk factors of asthma in relatively non-obese korean adults. Cigarette smokers, alcohol drinkers, patients with a family history of parent's asthma, and obesity may aggravate asthma, whereas regular exercise reduces the attacks of asthma.

Association of Body Fat and Body Mass Index with Pulmonary Function in Women in Their Forties

BACKGROUND: Obesity and decreased pulmonary function increase mortality and morbidity of diseases. Obesity is a major factor of decreased pulmonary function. There are variable results of how much body mass index (BMI) and body fat percent influence pulmonary function. There arefew data between obesity and pulmonary function in Korea. This study observed the association of BMI, body fat percent and pulmonary function, and quantified the impact of obesity to pulmonary function. METHODS: 603, non-smoking women in their forbles visited the Health Promotion Center of Inha University Hospital from January 3, 2000 to December 31 2000. Questions concerning smoking, exercise, and past medical history were made. Body fat percent and pulmonary function were measured. Correlation, simple linear regression and multiple linear regression between obesity indices and pulmonary function were used executed. RESULTS: BMI has no correlation with FVC, FEV1 and FEV1/FVC ratio. Body fat percent was negatively correlated with FVC and FEV1 (r=-0.162; P<0.01, r= -0.195; P<0.01), and was not correlated with FEV1/FVC ratio. In a multiple linar regression, body fat percent was inversely related to FVC and FEV1 (beta=-10.380; P<0.01, beta=-11.379; P<0.01). CONCLUSION: Increased body fat percent has association with decreased pulmonary function and has more impact on FEV1 than FVC. FVC was decreased by 10.380 mL and FEV1 was decreased by 11.379 mL when body fat percent increased by 1%.

Serum Leptin Levels in Children with Type I Diabetes Mellitus

PURPOSE: Leptin is a highly hydrophobic 16-kDa protein encoded by the ob gene which is expre- ssed in adipocytes and participates in the regulation of food intake and energy expenditure. The aims of the present study were to examine the comparison of leptin levels between type I diabetes mellitus (DM) patients who received exogenous insulin therapy and healthy children, and to find out correlating factors with leptin level in type I DM. METHODS: The study was conducted on 34 patients with type I DM and 29 healthy children. Body weight, height, leptin level and body fat percent were measured in both groups. The glycosylated hemoglobin value, C-peptide, insulin level and serum cholesterol were also measured in type I DM. RESULTS: There was no statistically significant difference in mean age, sex distribution and body mass index between the experimental groups, but body fat percent in type I DM was significantly lower than that of healthy children. The mean leptin levels in male (9.4+/-6.3ng/mL) and female (17.8+/-10.2ng/mL) type I DM were significantly higher than in male(6.3+/-5.7ng/mL) and female (10.2+/-0.9ng/mL) healthy children (male : P=0.045, female : P=0.005). Serum leptin levels were strongly correlated with the body fat percent (Pearson coefficient) (r=0.712). CONCLUSION: Serum leptin level in type I DM strongly correlated with the body fat percent. Despite lowered body fat percent in type I DM, the leptin level was significantly higher than values in healthy children. The mean leptin level in type I DM were significantly higher than value in healthy children, but body fat percent of type I DM was lower than value in healthy children who were adjusted for sex, age and body mass index.

The Study of Body Fat Percent Measured by Bioelectric Impedance Analyzer in a Rural Adult Population / 예방의학회지

Obesity usually is defined as the presence of and abnormally amount of adipose tissue. In many epidemiologic study, obesity as a health risk factor has been estimated by Body Mass Index(BMI) in general. This study was conducted to review of body fat percent measured by Bioelectric impedance analyzer as a estimator of obesity in a rural adult population. The study subjects were 421 men and 664 women who reside in the area on the Juam lake. They were sampled by multistage cluster sampling. Their mean age was 59 years old. Body fat percent increased with age, but BMI decreased with age in this study. Body fat percent was more larger at female and elder on the same BMI. The correlation coefficient between with body fat percent and body mass index was low (r=0.4737). Body fat percent was explained by not only BMI but also sex and age (r(2)=0.63). The result suggested that it is inadequate for BMI only to estimate obesity about elderly person who reside in the rural community. The relation of body fat percent and body mass index of this study agreed with the preceding knowledges and studies in general.

Relationship of Body Fat Percent with Serum Lipid Level and Blood Pressure in Adults / 예방의학회지

This study was conducted to clarify the relationship of body fat percent with serum lipid level and blood pressure in adults. The study subjects were 472 men and l89 women who visited Multiphasic Health screening center of Yeungnam university Hospital in Taegu from May 20 to September 30, 1994. The relationship of serum lipid and blood pressure with BMl, Katsura index, atherogenic index, which calculated from the health screening data and body fat percent measured by impedance fat meter(model SIF-819) were analyzed. Three groups were classified as Group I(men: body fat percent > or= 20, women: body fat percent > or= 25, Group II (men: 15 < or = body fat percent <20, women: 20 < or = body fat percent<25, Group III(men: body fat percent <15. women: body fat percent<20) In this study, Group I accounted for 3.2%in men, 3.7%in women. Weight was significantly different among three groups in both sexes(p<0.01) and height was not significantly different among three groups. In men, serum total cholesterol, triglyceride, high density lipoprotein, low density lipoprotein. atherogenic index were significantly different(p<0.01). In women, serum total cholesterol and low density lipoprotein were significantly different(p<0.05 but there was no differences in triglyceride and high density lipoprotein among three groups. BMl and Katsura index were significantly different among three groups in both sexes(p<0.01). In men, body fat percent was positively correlated with weight, BMl, Katsura index, total cholesterol, triglyceride, low density lipoprotein, atherogenic index and systolic and diastolic blood pressures, and negatively correlated with high density lipoprotein. In women, body fat percent was positively correlated with age, height, weight, BMl, Katsura index, total cholesterol, triglyceride, low density lipoprotein and atherogenic index, and negatively correlated with high density lipoprotein. But there was no significant correlation between body fat percent and blood pressure in women. In multiple regression analysis for total cholesterol, fat percent, age and BMl were significant independent variables in men(p<0.05, R2=0.1286), and body fat percent and age in women(p<0.05, R2=0.3399). In case of LDL/HDL ratio, only BMl was a significant independent variable in men(p<0.01, R2=0.0954), and body fat percent, age and BMl in women(p<0.05, R2=0.3164). In multiple regression analysis, age, low density lipoprotein and total cholesterol were significant independent variables on systolic blood pressure in men(p<0.05, R2=0.1297), age and total cholesterol in women(p<0.055, R2=0.1705). On diastolic blood pressure, only age was a significantly independent variable in men(p<0.01, R2=0.0972) and women(p<0.01, R2=0..1218). From the result of this study, it could concluded that body fat percent was significantly associated with other obesity indices and serum lipid, but had no significant association with blood pressure. To establish the relationship of body fat percent with blood pressure, further study which consider other variables that may have an effect on blood pressure should be performed.