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Background: Ethnic differences in cardiometabolic risk (CMR) may be related to patterns of ethnic-specific body fat distribution., Objective: We aimed to identify differences across ethnic groups in interrelations between BMI, abdominal adiposity, liver fat, and CMR profile., Design: In the International Study of Prediction of Intra-Abdominal Adiposity and Its Relationship With Cardiometabolic Risk/Intra-Abdominal Adiposity, 297 physicians recruited 4504 patients (from 29 countries). In the current cross-sectional analyses, 2011 whites, 166 African Caribbean blacks, 381 Hispanics, 1192 East Asians, and 347 Southeast Asians were included. Computed tomography was used to assess abdominal fat distribution and to estimate liver fat content. Anthropometric variables and CMR profile were measured., Results: Higher ranges of BMI were associated with higher levels of visceral [visceral adipose tissue (VAT)] and deep subcutaneous [deep subcutaneous adipose tissue (DSAT)] adiposity, with significant ethnic differences regarding the slope of these relations. Despite lower absolute BMI values, East Asians presented the largest accumulation of VAT but the lowest accumulation of DSAT with increasing adiposity. The association of BMI with liver fat did not differ between ethnic groups. Liver fat and DSAT were positively correlated with VAT with no ethnic variation. All ethnic groups had a similar association between a 1-SD increase in VAT, DSAT, or liver fat with hypertension, type 2 diabetes, hypertriglyceridemia, low HDL-cholesterol concentration, or high C-reactive protein concentration., Conclusions: Ethnicity significantly affects abdominal adiposity and liver fat partitioning, and East Asians have the most deleterious abdominal fat distribution. Irrespective of ethnicity, abdominal and hepatic fat depots are strongly interrelated and increased with obesity. Higher amounts of VAT or liver fat are associated with a more deteriorated CMR profile in all ethnic groups.

Background: C-reactive protein (CRP) concentrations have been found to be higher in premenopausal women than in men, whereas interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) concentrations have been reported to be lower in women than in men., Objective: The objective was to determine whether the sex difference in body fat distribution accounts for the observed sex differences in inflammatory markers., Design: Plasma CRP, IL-6, and TNF-alpha concentrations were measured in 208 healthy men (age: 42.2 +/- 15.2 y) and in 145 healthy women (age: 36.8 +/- 11.1 y)., Results: Compared with men, premenopausal women had higher CRP concentrations [1.24 (25th percentile: 0.54; 75th percentile: 3.04) compared with 0.94 (0.51, 2.40) mg/L; P < 0.05] and lower plasma TNF-alpha concentrations [1.50 (25th percentile: 1.23; 75th percentile: 1.82) compared with 1.71 (1.40, 2.05) pg/mL; P < 0.001]. No sex difference in IL-6 concentrations was noted. Regression analyses indicated that the relation between CRP or IL-6 and visceral adipose tissue (VAT) and subcutaneous AT (SAT) was sex-specific; a significantly steeper slope was observed in women than in men (P < 0.05). Sex differences in CRP concentrations were abolished after SAT was adjusted for. In a multivariate model of the whole sample, we found that both SAT and VAT and the sex x SAT interaction term were significant correlates of CRP and IL-6 concentrations. Finally, whereas CRP concentrations were largely influenced by visceral adiposity in men, subcutaneous adiposity was the key correlate of CRP in women., Conclusion: The higher CRP concentrations found in women appear to be due to their greater accumulation of subcutaneous fat than that observed in men.

Background: Dietary patterns play an important role in the control of body weight., Objective: The aim of this study was to verify whether changes in some dietary patterns over a 6-y follow-up period would be associated with weight changes., Design: A sample of 248 volunteers of the Québec Family Study were measured twice (visit 1: 1989-1994; visit 2: 1995-2000). Body weight, percentage body fat, subcutaneous skinfold thicknesses, and waist circumference measurements as well as 3-d dietary and physical activity records were obtained at each visit. At visit 2, all participants filled out a food-based questionnaire examining changes in the consumption of 10 food categories. To further investigate the relation between changes in food-group consumption and body-weight changes, a total of 51 food subcategories were identified from dietary records., Results: A self-reported decrease in the consumption of food in the fat group or an increase in consumption in the fruit group from the food-based questionnaire predicted a lower increase in body weight and adiposity indicators over time. A more detailed examination of the change in food groups between diet records revealed that increases in the consumption of whole fruit as well as skimmed milk and partly skimmed milk were the 2 food patterns that negatively correlated with the changes of each body weight-related indicator., Conclusions: These results show that changes in the consumption of some specific food groups are associated with body-weight changes. Such specific eating patterns could help to improve obesity treatment and prevention.

Background: Recent data suggest that variations in calcium intake may influence lipid metabolism and body composition., Objective: The association between daily calcium intake and body composition and plasma lipoprotein-lipid concentrations was studied cross-sectionally in adults from phase 2 of the Québec Family Study., Design: Adults aged 20-65 y (235 men, 235 women) were studied. Subjects who consumed vitamin or mineral supplements were excluded. Subjects were divided into 3 groups on the basis of their daily calcium intake: groups A (< 600 mg), B (600-1000 mg), and C (> 1000 mg)., Results: Daily calcium intake was negatively correlated with plasma LDL cholesterol, total cholesterol, and total:HDL cholesterol in women and men after adjustment for variations in body fat mass and waist circumference (P < 0.05). In women, a significantly greater ratio of total to HDL cholesterol (P < 0.05) was observed in group A than in group C after correction for body fat mass and waist circumference. In women, body weight, percentage body fat, fat mass, body mass index, waist circumference, and total abdominal adipose tissue area measured by computed tomography were significantly greater (P < 0.05) in group A than in groups B and C, even after adjustments for confounding variables. Comparable trends were observed in men, but not after adjustment for the same covariates., Conclusion: A low daily calcium intake is associated with greater adiposity, particularly in women. In both sexes, a high calcium intake is associated with a plasma lipoprotein-lipid profile predictive of a lower risk of coronary heart disease risk compared with a low calcium intake.

Background: Abdominal obesity has been associated with postprandial hypertriglyceridemia. The contribution of intestinally and hepatically derived lipoproteins to this exaggerated postprandial lipemic response is not known., Objective: We examined the associations between body fatness, fat distribution, and postprandial apolipoprotein (apo) B-48 and apo B-100 concentrations measured in triacylglycerol-rich lipoproteins (TRLs)., Design: Dietary fat tolerance was investigated in 50 men aged 28-67 y. The subjects were given a test meal containing 60 g fat/m(2) body surface area and providing 64% of energy from fat, 18% from carbohydrates, and 18% from protein. The meal provided 7524-9196 kJ, depending on body surface area. Blood samples were collected every 2 h over an 8-h period., Results: The increase in plasma triacylglycerol after the meal resulted from increases in both apo B-48- and apo B-100-containing lipoproteins. The apo B-100 concentration was the strongest contributor (R(2) = 69.6%, P = 0.0001) to postprandial triacylglycerol in total TRLs; the postprandial increase in triacylglycerol was best predicted by the apo B-48 concentration (R(2) = 32.7%, P = 0.0001). Visceral abdominal fat was significantly associated with high postprandial TRL apo B-48 and apo B-100 concentrations (r = 0.30-0.44, P < 0.05). After the meal, the apo B-100 concentration in small TRLs decreased in 12 subjects. These men showed features of the insulin resistance-dyslipidemic syndrome, including more visceral fat (P = 0.07) and an altered fasting metabolic profile., Conclusion: A lower lipolytic capacity may contribute to the exaggerated and prolonged postprandial lipemia among abdominally obese men.

Background: A high waist-to-hip ratio is associated with unfavorable cardiovascular disease risk factors. This could be due to either a relatively large waist or a small hip girth., Objective: We sought to define the separate contributions of waist girth, hip girth, and body mass index (BMI) to measures of body composition, fat distribution, and cardiovascular disease risk factors., Design: Three-hundred thirteen men and 382 women living in the greater Quebec City area were involved in this cross-sectional study. Percentage body fat, anthropometric measurements, and abdominal fat distribution were obtained and BMI (in kg/m2) and waist-to-hip ratio were calculated. Serum blood lipids were determined from blood samples collected after subjects had fasted overnight, Results: A large waist circumference in men and women (adjusted for age, BMI, and hip circumference) was associated significantly with low HDL-cholesterol concentrations (P < 0.05) and high fasting triacylglycerol, insulin, and glucose concentrations (P < 0.01). In women alone, a large waist circumference was also associated with high LDL-cholesterol concentrations and blood pressure. A narrow hip circumference (adjusted for age, BMI, and waist circumference) was associated with low HDL-cholesterol and high glucose concentrations in men (P < 0.05) and high triacylglycerol and insulin concentrations in men and women (P < 0.05). Waist and hip girths showed different relations to body fat, fat-free mass, and visceral fat accumulation., Conclusions: Waist and hip circumferences measure different aspects of body composition and fat distribution and have independent and often opposite effects on cardiovascular disease risk factors. A narrow waist and large hips may both protect against cardiovascular disease. These specific effects of each girth measure are poorly captured in the waist-to-hip ratio.

Background: Obesity is a major public health problem in the United States. The role of physical activity and formal exercise in controlling body weight has not been clearly determined., Objective: This study determined the magnitude of change in body weight and composition across sex, race, and age in response to 20 wk of endurance training., Design: Men and women (n = 557) of various ages (16-65 y) and 2 races (black and white) exercised on cycle ergometers 3 d/wk for a total of 60 exercise sessions starting at 55% of maximal oxygen consumption (VO(2)max) for 30 min/session and building to 75% of VO(2)max for 50 min/session, where it was maintained during the last 6 wk. Skinfold-thickness measurements, circumferences, body composition (by hydrostatic weighing), and body fat distribution (by computed tomography scan at L4-L5 and the waist-hip ratio) were determined before and after training., Results: All skinfold-thickness and circumference measures, waist-hip ratio, body mass index, total body mass, fat mass, percentage body fat, and computed tomography scan measures of total, subcutaneous, and visceral abdominal fat decreased with training, whereas total body density and fat-free mass increased. These changes were significant, but small. There were several differences in training response by sex and race, but not by age., Conclusions: A short-term exercise intervention can induce favorable changes in body composition, but the magnitude of these changes is of limited biological significance. Increasing physical activity likely has a major effect on body-composition and fat distribution characteristics only when it is of a greater magnitude and sustained for much longer periods

Our objective was to determine threshold values of waist girth, waist-to-hip ratio (WHR), and sagittal diameter corresponding to an accumulation of visceral adipose tissue of 130 cm2 and to verify whether these threshold values could be influenced by sex, age, menopausal status, and the degree of obesity. From the regression equations computed in the total sample of 213 men [aged (mean+/- SD) 37.8 +/- 12.2 y] and 190 women (aged 37.3 +/- 12.1 y), a waist girth of approximately 95 cm in both sexes, WHR values of 0.94 in men and of 0.88 in women, and sagittal diameters of 22.8 cm in men and 25.2 cm in women corresponded to a visceral adipose tissue area of 130 cm2. In both sexes, threshold values of waist girth corresponding to critical amounts of visceral adipose tissue were generally lower in subjects who were > or = 40 y old (approximately 90 cm) than in younger individuals (approximately 100 cm). Similar differences were found for WHR and sagittal diameter threshold values. Finally, threshold values of waist girth corresponding to critical amounts of visceral adipose tissue were essentially similar in normal-weight and overweight men and women, whereas threshold values of WHR were in general higher in normal-weight than in overweight subjects. In conclusion, our results suggest that the relations of anthropometric variables to visceral adipose tissue accumulation are age-specific. However, waist girth is likely to be a more convenient anthropometric correlate of visceral adipose tissue than the WHR because threshold values of waist girth corresponding to critical amounts of visceral adipose tissue do not appear to be influenced by sex or by the degree of obesity.

The effects of alcohol and dietary fat on spontaneous energy and macronutrient intakes were investigated in eight male subjects who participated in a protocol including four randomly assigned 2-d sessions during which they ate ad libitum. In each session they had free access to either high- or low-fat foods, with alcohol or a placebo. The high-fat diet was associated with a substantial increase in daily energy intake. Alcohol had no inhibitory effect on food intake and its energy content was thus associated with an additional increase in energy intake. The enhancing effects of alcohol and dietary fat on daily energy intake were additive so that overfeeding was maximal (2.8 MJ/d) under the high-fat diet+alcohol condition. To further examine the effects of alcohol on energy and macronutrient intakes, reported food intake was studied in 351 men and 360 women who had been tested in the Québec Family Study. The results showed that a high alcohol intake was associated with a high daily energy intake and had no inhibitory effect on lipid intake. In conclusion, a dietary regimen providing a high fraction of energy as alcohol and fat increases the risk for positive energy balance under free-living conditions.

Recent data suggest that hyperinsulinemia with euglycemia may favor the restoration of energy balance when one gains body weight. To test the validity of this concept in humans, the data of 24 young men who had been exposed to a 353-MJ overfeeding protocol for 100 d and who were remeasured after a 4-mo follow-up were analyzed. The sample was subdivided in two groups on the basis of the overfeeding-induced change in postprandial plasma insulin. The increase in postprandial energy expenditure induced by overfeeding was significantly greater in high than in low postprandial insulin responders (P < 0.05) but not after body fat gain was controlled for. After the overfeeding protocol, the loss of subcutaneous adiposity was greater in high than in low postprandial insulin responders. However, this difference was no more significant after the gain in fat mass was controlled for. There was no difference between the two groups in post-overfeeding loss of body weight, fat mass, or fat-free mass. These results partly agree with the idea that hyperinsulinemia resulting from a long-term positive energy balance and its associated fat gain exert a regulatory role promoting the restoration of energy balance.

This study was aimed at investigating the effect of exercise on energy balance under dietary conditions differing by the relative lipid content of foods. Nine healthy men performed a 60-min treadmill exercise followed by a 48-h observation period during which they maintained their habitual daily activities and had free access to either a low-fat, a mixed, or a high-fat diet. Energy balance, summing up the excess of energy expended during exercise and the 48-h postexercise energy balance, was -6.4, -4.5, and 0.9 MJ under low-fat, mixed, and high-fat diet conditions, respectively. These observations suggest that exercise can induce a substantial energy deficit when a low-fat diet conforming to nutritional recommendations is consumed after exercise. They also suggest that the increase in energy intake associated with a high-fat diet is sufficient to fully compensate for the energy deficit resulting from the energy cost of exercise and the increase in postexercise energy expenditure.

The associations between the amount of abdominal adipose tissue (AT) measured by computed tomography (CT) or estimated with predictive equations and the amount of total body fat were compared in samples of 89 men and 75 women. After correction for total body fat mass, men had significantly higher values of visceral AT volume (P < 0.0001) and also higher abdominal visceral AT areas, measured by CT or estimated by predictive equations than women (P < 0.0001). In addition, an increase in total fat mass was associated with a significantly greater increase in visceral AT volume in men than in women (P < 0.0001). In conclusion, these results suggest that the greater health hazards associated with excess fatness in men than in women may be explained by the fact that premenopausal women can accumulate more body fat than men of the same age before reaching the amounts of visceral AT found in men.

This report deals with the association between the constituents of lean body mass (LBM) and resting metabolic rate (RMR) before and after a 100-d overfeeding period. Computed-tomography (CT) scan of 22 young adult males at nine different body levels were used to estimate adipose tissue mass (ATMCT), LBMCT, skeletal-muscle mass (SMMCT), and non-muscular LBMCT (NM-LBMCT). Before overfeeding, all body constituents, except ATMCT, were significantly correlated with RMR. Only body mass changes were significantly correlated with RMR changes. Comparison of these results with those of several studies in the literature reveals that the relationship between RMR and fat-free mass is highly influenced by the size of the SD for the latter variable. In stepwise-multiple-regression analysis, only SMMCT could be used to predict RMR. It was concluded that SMMCT and ATMCT, but not NM-LBMCT, increased during overfeeding and that the best correlates of RMR remain LBMCT, SMMCT, and body mass.

The effect of overfeeding on energy expenditure was investigated in 23 young men subjected to a 353-MJ energy intake surplus over 100 d. The major part of this excess (222 MJ) was stored as body energy. The increase in energy cost of weight maintenance amounted to 52 MJ and was proportional to body weight gain. When it was added to the obligatory cost of fat and fat-free mass gains, the overall increase in energy expenditure amounted to a mean of 100 MJ. Four months after overfeeding, subjects had lost 82%, 74%, and 100% of the overfeeding gain in body weight, fat mass, and fat-free mass, respectively. We conclude that 1) in response to overfeeding, two-thirds of the excess energy intake is stored as body energy; 2) overfeeding induces an increase in energy cost of weight maintenance proportional to body weight gain, and 3) preoverfeeding energy balance tends to be restored when nonobese individuals return to their normal daily-life habits.

Equations have been developed for the prediction of deep abdominal adipose-tissue (AT) accumulation from anthropometric measurements in a sample of 110 men. An equation including the waist circumference and age could predict 74% of the variance in the amount of deep abdominal AT with an SEE of 29.6 cm2 (29.2% of the mean deep abdominal AT value), whereas another equation including the sagittal diameter, the waist-to-hip ratio (WHR), and age explained 76.6% of its variance with an SEE of 28.1 cm2 (27.7%). Equations excluding age as an independent variable were also developed. These results indicate that equations in which simple anthropometric measurements are used can provide further information in the assessment of the risk of cardiovascular disease in men. However, we must remember that our ability to predict the amount of deep abdominal AT from anthropometry is limited.

Two studies were performed to evaluate the short-term effect of a high-fat diet on spontaneous energy intake and the respective contribution of diet composition and energy density of food. Ingestion of high-fat foods was associated with a significant increase in energy intake in the two studies (P less than 0.05). In study 1 this increase was accompanied by a reduction in total weight of food consumed when compared with values obtained under low-fat-diet conditions. Moreover, the occurrence of satiety coincided with a level of carbohydrate intake corresponding to the expected daily carbohydrate oxidation when high-fat foods contained a moderate amount of carbohydrates. In study 2, where the carbohydrate content of high-fat foods was unusually low (less than or equal to 25% of their energy content), carbohydrate intake was lower than usual carbohydrate oxidation. Under the conditions of this study, energy density of foods seemed to play a significant role on the occurrence of satiety.

To evaluate the effect of intensity of physical activity on body fatness and fat distribution, observations of 1366 women and 1257 men who participated in the 1981 Canada Fitness Survey were analyzed. Subjects were tested for energy expenditure of leisure-time activities and estimated maximal oxygen uptake (VO2max), body fatness was measured by subcutaneous skinfold thicknesses, and anthropometric measurements were made. Subjects of both sexes were categorized into four subgroups on the basis of their participation in leisure-time activities of various intensities. In general, subjects practicing vigorous activities on a regular basis had lower subcutaneous skinfold thicknesses and waist-to-hip ratios (WHRs) than those not performing these activities. These differences remained statistically significant after a covariance analysis was used to remove the effect of total energy expenditure of leisure-time activities on subcutaneous fat and fat distribution. Moreover, the WHR remained significantly lower in subjects performing high-intensity exercise after the effect of subcutaneous fat on fat distribution was adjusted for.

This study investigated the effects of overfeeding on the body composition and fat morphology characteristics of 6 pairs of male monozygotic twins. Each participant was submitted to a 22-day overfeeding period, supplemented by an additional 1000 kcal/day. Significant changes were observed in body composition and fat morphology as shown by increases in body weight, fat mass, sum of 9 skinfolds, and fat cell diameter. Significant within-pair resemblance for absolute changes was observed for body weight, percent body fat, fat mass, sum of skinfolds, trunk skinfolds, and extremity skinfolds, suggesting a role for the genotype in determining the sensitivity of the response to an energy surplus. Significant within-pair resemblance was noted for the biceps, triceps, and thigh with less resemblance noted in the subscapular, abdomen, suprailiac, calf, axillary, and chest sites, suggesting a variation in genotype dependency for subcutaneous fat. The results suggest that changes in body fat following short-term overfeeding appear to have a genetic basis.