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The relative contribution of circulating glucose to meal-to-meal variability in energy intake is not known. In 8 free-living young (median age 26.5 y) women with healthy body weight (median BMI 22.2 kg/[m.sup.2]), we measured glucose in the interstitial space by an automated monitoring procedure (continuous glucose monitoring system, CGMS[TM]) for up to 3 consecutive days (mean 706 glucose readings per subject). We examined the association between interstitial glucose (which lags blood glucose by ~10 min), self-reported hunger, satiety, desire for a meal, and nutrient intakes. Participants reported consuming a typical Western diet (59% carbohydrate, 27% fat, 14% protein). Median (interquartile range) interstitial glucose was 5.2 mmol/L (4.7-5.8). Using repeated-measures techniques in univariate analyses, desire for a meal (r = 0.45, P < 0.0001), hunger (r = 0.37, P = 0.0002), satiety (r = -0.40, P < 0.0001), low interstitial absolute mean glucose up to 25 min before eating (r = -0.23, P = 0.02), and a large decline in glucose between 40 and 5 min before eating (r = -0.17, P = 0.08) were all associated with meal energy intake. In multivariate regression analyses, desire for a meal (P < 0.0001) and hunger (P = 0.02) were the strongest independent contributors to meal energy intake, whereas absolute mean glucose measured in the period 15 to 0 min before eating was marginally significant (P = 0.08). In conclusion, absolute glucose level is a significant predictor of energy intake in nonobese women. However, desire for a meal and hunger are quantitatively more important, emphasizing the importance of both glucose signals and nonglucose (internal or environmental) factors in within-subject variability in energy intake. In addition, the CGMS may have utility in understanding the role of circulating glucose in energy regulation in free-living subjects under a wide range of different nutritional conditions. KEY WORDS: * glucose * energy * hunger * satiety * free-living

To test the hypothesis that total energy expenditure (TEE) and resting energy expenditure (REE) are low in extremely obese individuals, factors that could contribute to maintenance of excess weight, a cross-sectional study was conducted in 30 weight stable, extremely obese women [BMI (mean [+ or -] SEM) 48.9 [+ or -] 1.7 kg/[m.sup.2]]. TEE was measured over 14 d using the doubly labeled water method, REE and the thermic effect of feeding (IEF) were measured using indirect calorimetry, and activity energy expenditure (AEE) was calculated as TEE--(REE + TEF). Body composition was determined using a 3-compartment model. Subjects were divided into tertiles of BMI (37.5-45.0; 45.1-52.0; and 52.1-77.0 kg/[m.sup.2]) for data analysis. TEE and REE increased with increasing BMI tertile: TEE, 12.80 [+ or -] 0.5, 14.67 [+ or -] 0.5, and 16.10 [+ or -] 0.9 MJ/d (P < 0.01); REE, 7.87 [+ or -] 0.2, 8.78 [+ or -] 0.3, and 9.94 [+ or -] 0.6 MJ/d (P < 0.001), and these values were 29-38% higher than published means of measured TEE in nonobese individuals. No significant differences were observed among BMI tertiles for AEE, TEF, or physical activity level (PAL = TEE/REE, overall mean 1.64 [+ or -] 0.16). The Harris-Benedict and WHO equations provided the closest estimates of REE (within 3%), whereas the obese-specific equations of Ireton-Jones overpredicted (40%) and Bernstein underpredicted (21%) REE. Extremely obese individuals have high absolute values for TEE and REE, indicating that excess energy intake contributes to the maintenance of excess weight. Standard equations developed for nonobese populations provided the most accurate estimates of REE for the obese individuals studied here. REE was not accurately predicted by equations developed in obese populations. J. Nutr. 134: 1412-1416, 2004. KEY WORDS: * extreme obesity * energy expenditure * fat-free mass * prediction equations

To identify existing dietary patterns and examine associations between these patterns and plasma homocysteine and B vitamin concentrations in an urban Chinese population living in Beijing (n = 119), dietary information was collected with a food frequency questionnaire designed for this population. Plasma homocysteine and B vitamin concentrations were examined. Food group variables, expressed as percentages of total energy intake, were entered into cluster analysis to define three distinct dietary pattern groups. The prevalence of high homocysteine (>11 [micro]mol/L for women and 12 [micro]mol/L for men), was 31.9%; of low folate ( KEY WORDS: * dietary patterns * homocysteine * B vitamin * cluster analysis * Chinese

Little is known about the relative effects of fermentable fiber (FF) vs. nonfermentable fiber (NFF) on energy regulation in humans. We compared 27 [+ or -] 0.6 g/d supplements of FF (pectin,/[beta]-glucan) and NFF (methylcellulose) for their ability to decrease ad libitum energy intake (El) and hunger, increase satiety and cause spontaneous body weight and fat losses. Men and women (n = 11) aged 23-46 y, BMI 20.0-34.4 kg/[m.sup.2], consumed first NFF and then FF for 3 wk each, with a 4-wk washout period between phases. Daily satiety assessed with analog scales was higher with NFF than FF (60.7 [+ or -] 1.0 vs. 57.7 [+ or -] 0.8 mm, P = 0.01). However, there were no differences in reported El (NFF < FF by 7%, P = 0.31, NFF < baseline by 9.5%, P = 0.11), body weight (NFF 0.13 kg, P = 0.73; FF 0.13 kg, P = 0.60) or fat percentage (NFF -0.3%, P = 0.56; FF -0.1%, P = 0.66) within either phase. In contrast to findings in animals, NFF was more, rather than less satiating than FF, and use of neither NFF nor FF preparations was associated with body weight or fat loss. These pilot results suggest no role for short-term use of FF and NFF supplements in promoting weight loss in humans consuming a diet ad libitum. J. Nutr. 133: 3141-3144, 2003. KEY WORDS: * fiber * fermentable * nonfermentable * satiety * weight loss

U.S. adults are now gaining more weight and becoming obese at an earlier age than in previous years. The specific causes of adult weight gain are unknown, but may be attributed to a combination of factors leading to positive energy balance. U.S. food supply data indicate that Americans have had a gradual increase in energy intake since 1970, and that per capita energy intake was 1.42 MJ/d (340 kcal/d) higher in 1994 than that in 1984. In contrast, self-reported physical activity remained constant between 1990 and 1998. Taken together, these data indicate that the increasing trend in U.S. adult weight gain is primarily attributable to overconsumption of energy. Epidemiological and experimental studies in animals and humans provide strong evidence that biobehavioral factors such as dietary variety, liquid (vs. solid) energy, portion size, palatability (taste), snacking patterns, restaurant and other away-from-home food, and dietary restraint and disinhibition influence hunger, satiety and/or voluntary energy intake. When these eating behaviors are consistently experienced either separately or in combination over the long term, they are likely to facilitate overeating. We provide a brief overview of the evidence to date for the role of these biobehavioral factors in contributing to excess energy intake and increases in body weight over time. J. Nutr. 132: 3830S-3834S, 2002. KEY WORDS: * obesity * weight gain * energy intake * energy balance * biobehavioral factors

There is little information on the accuracy of simple body composition methods in non-Western populations. We determined the percentage of body fat (%BF) by isotope dilution [oxygen-18 ([H.sub.2][sup.18]O) and deuterium oxide ([sup.2][H.sub.2]O)] and anthropometry in 71 healthy, urban Chinese adults aged 35-49 y [body mass index (BMI) 18-35 kg/[m.sup.2]]. The accuracy of several prediction equations for assessment of %BF from skinfold measurements was evaluated against %BF determined by [H.sub.2][sup.18]O dilution. We also assessed the relationship between BMI and %BF, and the fat-free mass (FFM) hydration coefficient for our population. All skinfold equations yielded means within ~2%BF of [H.sub.2][sup.18]O-derived %BF. However, on the basis of residual plot analysis and the 95% confidence interval (Cl) for the mean difference between methods, the equations of Durnin and Womersley (for assessment of body density from skinfolds) coupled with that of Brozek et al. (for assessment of %BF from body density) provided the most valid assessment for individuals. In addition, the FFM hydration coefficient averaged 0.734 [+ or -] 0.002 (SEM), indicating that the usually assumed value of 0.732 is appropriate for this population. Finally, although BMI had high specificity (90%) for classifying individuals as having body fat within the normal range (30%BF. J. Nutr. 132: 310-317, 2002. KEY WORDS: * isotope dilution * anthropometry * body mass index * percentage of body fat * fat-free mass hydration coefficient

Previous studies by our group and others have suggested that nutritional stunting may increase the risk of obesity. To investigate mechanisms that could explain a link between stunting and obesity, a 22-mo follow-up study was conducted in two groups of shantytowns school girls (7-11 y old) in Sao Paulo, Brazil. One group (n = 15) had mild stunting (defined using a cutoff of -1.4 Z-scores of height-for-age) but normal weight-for-height; the control group (n = 15) had normal weight and height. Similar energy intake, dietary macronutrient composition and energy expenditure were observed in the two groups. Both groups showed comparable levels of IGF-1 that were below the normal range. A significant and positive association between baseline IGF-1 and the change in height-for-age during follow-up was found in all subjects combined (P = 0.044). A significant association was found between the baseline percentage of dietary energy supplied by fat and the gain in weight-for-height during follow-up in girls with mild stunting (P = 0.048), but not in the nonstunted control girls (P = 0.245); however, the slopes of these relationships were not significantly different. This study raises the question of whether a diet high in fat may increase the susceptibility to excess body fat gain in children who are mildly stunted. Further studies are need to explore this issue and to examine the possible etiological role of low levels of IGF-1. KEY WORDS: stunting; malnutrition; obesity; body composition

We investigated the importance of adaptive variations in energy expenditure in the regulation of energy balance in young and elderly men of normal body weight leading unrestricted lives. Changes were measured in total and resting energy expenditure and body composition in response to overeating by approximately 4.2 MJ/d or undereating by 3.3 MJ/d for 21 d in 39 young and elderly men consuming a typical diet. In the young men, an average of 85-90% of the excess energy intake during overeating was deposited. During underfeeding, mobilization of body energy compensated for an average of 65% of the energy deficit in these subjects. The resting metabolic rate, averaged for fasting and fed states, increased during overfeeding (+0.63 plus or minus 0.20 MJ/d, P < 0.01) and decreased during underfeeding (-0.42 plus or minus 0.12 MJ/d), but at least some of these changes were due to the obligatory expenditure associated with nutrient assimilation. There was no significant change in energy expenditure for physical activity or thermoregulation from overfeeding or underfeeding. Preliminary results indicate that aging had no effect on responses to overfeeding or underfeeding. These findings suggest that adaptive variations in energy expenditure are not the major determinant of energy regulation in young adults of normal body weight and that, instead, energy balance is maintained on a day-to-day basis through the control of nutrient intakes.

We tested the hypothesis that nutritionally stunted children have impaired regulation of energy intake (EI), a factor that could help explain the increased risk of obesity associated with stunting in developing countries. A 3-d residency study was conducted in 56 prepubertal boys and girls aged 8-11 y from the shantytowns of Sao Paulo, Brazil. Twenty-seven of the subjects were stunted and 29 were not stunted; weight-for-height Z-scores were not significantly different between the groups. Parents of the two groups had equivalent heights and body mass indices. Measurements were made of voluntary EI from a self-selection menu, resting energy expenditure (REE) and body composition. In addition, a 753-kJ yogurt supplement was administered at breakfast on one study day (with an equal number of children receiving the supplement on each of the 3 study days) and its effect on daily EI assessed. There was no change in EI over time in either group (P = 0.957), and no significant difference in EI between stunted and nonstunted children, even though the stunted children weighed 10% less. Energy intake per kilogram body weight was significantly higher in the stunted children (278 [+ or -] 89 (SD), VS. 333 [+ or -] 67 kJ/kg, P [is less than] 0.05) and EI/REE was also significantly higher (1.91 [+ or -] 0.34 vs. 1.68 [+ or -] 0.38, P [is less than] 0.05). However, the relationship between EI and body weight was not significantly influenced by stunting (P = 0.12). There was no significant effect of the breakfast supplement on daily EI in either group although the absolute difference in EI between supplement and control days was greater in stunted than in nonstunted children ([Delta]EI: +460 [+ or -] 1574 vs. -103 [+ or -] 1916 kJ/d, P = 0.25). These data provide preliminary evidence consistent with the suggestion that stunted children tend to overeat opportunistically, but further studies are required to confirm these results in a larger study. J. Nutr. 130: 2265-2270, 2000. KEY WORDS: * humans * energy intake * malnutrition * hunger * satiety