Effects of equal weight loss with orlistat and placebo on body fat and serum fatty acid composition and insulin resistance in obese women

BACKGROUND: Dietary fat has been reported to influence insulin sensitivity. OBJECTIVE: The objective of the study was to determine how identical weight loss (target: loss of 8% of body weight over 3-6 mo) in women taking orlistat or placebo combined with a hypocaloric diet influences body composition and insulin sensitivity. DESIGN: Forty-seven obese women [body mass index (in kg/m(2)): 32.1 +/- 0.4] were randomly assigned to receive either orlistat (120 mg 3 times daily; n = 23) or placebo (n = 24) with a hypocaloric diet. Whole-body insulin sensitivity (insulin clamp technique), serum fatty acids, and body composition (magnetic resonance imaging) were measured before and after weight loss. RESULTS: The groups did not differ significantly at baseline with respect to age, body weight, intraabdominal and subcutaneous fat volumes, or insulin sensitivity. Weight loss did not differ significantly between the orlistat (7.3 +/- 0.2 kg, or 8.3 +/- 0.1%) and placebo (7.4 +/- 0.2 kg, or 8.2 +/- 0.1%) groups. Insulin sensitivity improved significantly (P < 0.001) and similarly after weight loss in the orlistat (from 4.0 +/- 0.3 to 5.1 +/- 0.3 mg x kg fat-free mass(-1) x min(-1)) and placebo (from 4.4 +/- 0.4 to 5.4 +/- 0.4 mg x kg fat-free mass(-1) x min(-1)) groups. Intraabdominal fat and subcutaneous fat decreased significantly in both groups, but the ratio of the 2 decreased significantly only in the orlistat group. The proportion of dihomo-gamma-linolenic acid (20:3n-6) in serum phospholipids was inversely related to insulin sensitivity both before (r = -0.48, P < 0.001) and after (r = -0.46, P < 0.001) weight loss, but it did not change significantly in either group. CONCLUSIONS: Weight loss rather than inhibition of fat absorption enhances insulin sensitivity. A decrease in fat absorption by orlistat appears to favorably influence the ratio between intraabdominal and subcutaneous fat, which suggests that exogenous fat or its composition influences fat distribution.     

Lean body mass changes in cancer patients with weight loss

BACKGROUND AND AIMS: Metabolic measurements (e.g. resting energy expenditure) are adjusted to lean body mass to account for body composition differences. Usually lean body mass is estimated from total body water. However, this may be compromised in weight-losing cancer patients owing to alterations in the degree of hydration of the lean body mass. This study examined the relationship between two independent estimates of lean body mass in healthy subjects and cancer patients with weight loss. METHODS AND RESULTS: Height, weight, total body water and total body potassium were measured in healthy subjects (n=9) and weight losing cancer patients (n=13). They were similar in terms of age and gender. However, the cancer group had a significantly lower percentage ideal body weight (P<0.001). The measured total body water values in both groups were similar to those predicted. In contrast, measured total body potassium values in the cancer group were significantly lower than predicted (P<0.001). There was a correlation between the ratio of measured lean body mass (water/lean bodymass (potassium) and the percentage weight loss (r=0.698, P<0.001). CONCLUSIONS: These results suggest that total body water significantly overestimates metabolically active tissue in weight-losing cancer patients and therefore its use as the basis for metabolic requirements in this group of patients is questionable.     

Changes in body weight and body fat distribution as risk factors for clinical diabetes in US men

Although previous studies have linked obesity to diabetes, the risks associated with weight gain or changes in body fat distribution have not been fully elucidated. The authors therefore prospectively examined the relations between changes in body weight and body fat distribution (1986-1996) and the subsequent risk of diabetes (1996-2000) among 22,171 men in the Health Professionals Follow-up Study. Weight gain was monotonically related to risk, and for every kilogram of weight gained, risk increased by 7.3%. A gain in abdominal fat was positively associated with risk, independent of the risk associated with weight change. Compared with men who had a stable waist, men who increased waist circumference by 14.6 cm or more had 1.7 (95% confidence interval: 1.0, 2.8) times the risk of diabetes after controlling for weight gain. In contrast, men who lost more than 4.1 cm in hip girth had 1.5 (95% confidence interval: 1.0, 2.3) times the risk of diabetes compared with men with stable hip circumference. Fifty-six percent of the cases of diabetes in this cohort could be attributed to weight gain greater than 7 kg, and 20 percent of the cases could be attributed to a waist gain exceeding 2.5 cm. Our findings underscore the critical importance of maintaining weight and waist to reduce the risk of diabetes.     

Influence of eating behaviors on short-term weight loss by orlistat and anorectic agent

Little data exists concerning whether eating behaviors determine the response to orlistat treatment, especially with added anorectic agents. This study was a sub-investigation of a 12-week randomized controlled trial for the additive effect of orlistat on sibutramine treatment. The analysis presented here was restricted to 98 women who had fulfilled the protocol. The Dutch eating behavior questionnaire and three-factor eating questionnaire were used to assess eating behaviors. Scores of emotional eating, external eating, disinhibition and hunger are significantly interrelated. Using multiple logistic analysis with adjustment for potential confounders, such as age, initial BMI and the other 2 eating behavior scores, traits of emotional eating (OR 0.30, 95% CI 0.13–0.74) and disinhibition (OR 0.61, 95% CI 0.40–0.82) have a significant influence on prediction for additional 5% weight loss in the treatment with orlistat and sibutramine. Subjects with less vulnerability to emotional cues had significantly more weight loss with orlistat treatment and anorectic agents.     

中学生体质量指数及减肥行为与体重认知错误的关系

了解无锡市青少年体质量指数状况及减肥行为与体重认知错误之间的相关关系,为保障身心健康发展提供支持.方法 在无锡市方便抽取4所中学的960名中学生进行问卷及身高、体重的测试,分析体重认知错误与减肥行为之间的关系.结果 无锡市中学生体型消瘦的比例为6.77%,超重肥胖的比例为26.77%.中学生高估自身体重的报告率为29.58%,低估的报告率为33.33%,认知正确的报告率为37.08%.男生高估体重的报告率为18.01%,女生为41.53%,差异有统计学意义(x2=63.57,P<0.01);男生低估体重的报告率为45.08%,女生为21.19%,差异有统计学意义(x2=61.65,P<0.01).Logistic回归分析显示,认为超重肥胖的中学生无论客观体重如何,与自认为体重正常的学生相比发生减肥行为的可能性高达109.75倍(P<0.01).对自身体重高估的中学生比正确认知体重学生更容易发生减肥行为[OR值(OR值95%CI)=10.44(7.01~15.55),P<0.01],并且男生和女生存在同样的趋势.结论 应对无锡市中学生的体重观进行干预和引导,以形成正确的体重观念,保障身心健康发展.     

Gender differences in body mass index and weight loss strategies among African Americans

The goals of this study were to examine gender differences in body satisfaction, obesity status, and weight loss strategies among African Americans. A self-administered survey was completed by a convenient sample of 789 African Americans, but 763 provided weight and height information. Significantly more men than women were satisfied or very satisfied with their weight. Based on self-reported weights, the mean body mass index for both men (26.61+/-4.23) and women (26.44+/-5.80) was greater than 25, thus classifying them as being overweight. Sixty-two percent of respondents had tried to lose weight in the last 12 months, with significantly more women trying to lose weight than men (P<.0001). Of those who tried to lose weight, most tried to lose weight by decreasing fried foods, decreasing sweets, and increasing exercise levels. Women were significantly more likely than men to use liquid meals, to use diet pills, to join a weight loss program, and to increase exercise levels to lose weight (P<.05).     

Effect of conjugated linoleic acid supplementation on weight loss and body fat composition in a Chinese population

ObjectiveConjugated linoleic acid (CLA) has several benefits, including body fat reduction, as proved in animals. However, the results of CLA-induced body composition alterations in humans are inconsistent, and no related data are available for Chinese populations. This study aimed to determine whether CLA affects body weight (BW) loss and body composition of overweight and obese Chinese subjects.MethodsIn this randomized, double-blind, placebo-controlled trial, subjects with a body mass index (BMI) of 24 to 35 kg/m² randomly received 1.7 g of cis-9,trans-11 and trans-10,cis-12 CLA (n = 30) or placebo (salad oil; n = 33) in 200 mL of sterilized milk twice daily for 12 wk. Changes in body composition were determined by bioimpedance measurements.ResultsSixty-three subjects completed the study (CLA, n = 30). After 12 wk, compared with the baseline, the BW, BMI, total fat mass, fat percentage, subcutaneous fat mass, and waist-to-hip ratio decreased in the CLA group (P < 0.05). The CLA group was stratified by BMI and gender. The BW, BMI, subcutaneous fat mass, and waist-to-hip ratio decreased in 27 subjects with a BMI ≥ 27, and these indices, except subcutaneous fat mass, were lower in female subjects. The levels of total cholesterol, triacylglycerol, low-density lipoprotein, and plasma fasting glucose increased, whereas those of high-density lipoprotein decreased after 3 mo of CLA treatment. The changes were not significantly different from the baseline values.ConclusionThe supplementation of CLA for 12 wk in overweight and grade I obese Chinese subjects yielded lower obesity indices, with no obvious adverse effects.     

Multimodal-lifestyle intervention produces reduction of the fat mass rather than body weight loss in men with obesity: A prospective cohort study

Background and the objectiveBody composition changes throughout the multimodal-lifestyle intervention of obesity is underinvestigated. This study evaluated the effectiveness of the multimodal-lifestyle intervention in reduction of fat mass together with preservation of fat free mass.MethodsAdult male subjects with overweightness or obesity (n = 99) were enrolled in a prospective cohort study for 12 months. Patients were educated about healthy diet, physical activity, and some behavioral changes. Anthropometric measurements and body composition analysis by bioelectric impedance analysis (InBody-720) were reported before, during and after the study period.ResultsConcerning adherent subjects, the mean ± standard error of the mean (SEM) of percent weight loss, percent fat mass loss, percent fat free mass and total body water changes after 6 months were 7.24 ± 0.98, 16.28 ± 2.35, 0.76 ± 0.64 and 0.82 ± 0.65, respectively, and after 1 year they were 10.14 ± 0.78, 25.22 ± 3.59, 1.22 ± 1.06 and 1.27 ± 1.07, respectively. There were significant changes between before- and after-measurements of weight, BMI, waist circumference, fat mass and percent body fat (P < 0.05) for all studied intervals.ConclusionsMultimodal-lifestyle intervention might be effective in loss of fat mass rather than reduction of the total body weight together with preservation of the lean body mass.     

Risk factors for hepatitis B virus infection in US Army soldiers in Europe.

Cross-sectional and case-control studies were conducted in a US Army unit which had experienced a protracted outbreak of viral hepatitis. Serological, demographic, and exposure data were collected. The cross-sectional study found that there was no association between the prevalence of hepatitis B virus (HBV) infection and ethnicity, education, and rank. There was an association with age and duration of assignment to the unit. Having social contact with an identified hepatitis patient and the sharing of personal hygiene items with a case were significant risk factors for HBV infection. Through the use of anonymous questionnaires, the case-control study evaluated various behavioural factors. Univariate analysis indicated moderate but not significant increases in risk associated with a history of multiple sex partners and a history of disciplinary problems while in the military. Six drug-use related risk factors were significantly associated with HBV infection on univariate analysis. When evaluated with multivariate analysis, the only risk factor that was significantly associated with HBV infection was injection of drugs while assigned to the study unit. Two sources of misclassification bias were identified, both of which acted to underestimate the true risk associated with identified risk factors.     

The relationship between body fat mass and fat-free mass

It has been suggested that there is a curvilinear relationship between lean body or fat-free mass and body fat mass. In order to confirm this relationship, body composition was measured by determining body density and total body water using deuterium-labeled water in subjects varying widely in body fat mass. There were 29 males and 75 females with body mass index ranging from 20 to 66 kg/m2. The relationship between fat-free mass and fat mass appeared to be linear over the range of body fat from 10 to 90 kg: males R2 = 0.67 (p less than 0.0001) and females, R2 = 0.47 (p less than 0.0001). The amount of variance explained was not greater when the log of fat mass was used in place of fat mass alone. Multiple regression analysis demonstrated that the relationship between fat-free mass and fat mass remained significant (p less than 0.001) after adjusting for body height, age, and fat distribution. It is concluded that over the range of body fat extending from 10 to 90 kg there is a positive and linear relationship between fat-free body mass and fat mass.