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Background: Calorie restriction (CR) retards aging and increases longevity in many animal models. However, it is unclear whether CR can be implemented in humans without adverse effects on body composition. Objective: We evaluated the effect of a 2-y CR regimen on body composition including the influence of sex and body mass index (BMI; in kg/m 2 ) among participants enrolled in CALERIE-2 (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy), a multicenter, randomized controlled trial. Design: Participants were 218 nonobese (BMI: 21.9-28.0) adults aged 21-51 y who were randomly assigned to 25% CR (CR, n = 143) or ad libitum control (AL, n = 75) in a 2:1 ratio. Measures at baseline and 12 and 24 mo included body weight, waist circumference, fat mass (FM), fat-free mass (FFM), and appendicular mass by dual-energy X-ray absorptiometry; activity-related energy expenditure (AREE) by doubly labeled water; and dietary protein intake by self-report. Values are expressed as means ± SDs. Results: The CR group achieved 11.9% ± 0.7% CR over 2-y and had significant decreases in weight (-7.6 ± 0.3 compared with 0.4 ± 0.5 kg), waist circumference (-6.2 ± 0.4 compared with 0.9 ± 0.5 cm), FM (-5.4 ± 0.3 compared with 0.5 ± 0.4 kg), and FFM (-2.0 ± 0.2 compared with -0.0 ± 0.2 kg) at 24 mo relative to the AL group (all between-group P < 0.001). Moreover, FFM as a percentage of body weight at 24 mo was higher, and percentage of FM was lower in the CR group than in the AL. AREE, but not protein intake, predicted preservation of FFM during CR ( P < 0.01). Men in the CR group lost significantly more trunk fat ( P = 0.03) and FFM expressed as a percentage of weight loss ( P < 0.001) than women in the CR group. Conclusions: Two years of CR had broadly favorable effects on both whole-body and regional adiposity that could facilitate health span in humans. The decrements in FFM were commensurate with the reduced body mass; although men in the CR group lost more FFM than the women did, the percentage of FFM in the men in the CR group was higher than at baseline. CALERIE was registered at clinicaltrials.gov as NCT00427193., (© 2017 American Society for Nutrition.)

Purpose: Obesity is a coronary disease risk factor, but its independent effect on clinical outcomes following acute coronary syndromes has not been quantified. We evaluated the relationship between elevated body mass index (BMI) and 30-day, 90-day, and 1-year clinical outcomes postacute coronary syndromes., Subjects and Methods: Using 15 071 patients (normal weight [BMI = 18.5-24.9 kg/m(2)], overweight [BMI = 25-29.9 kg/m(2)], obese [BMI = 30-34.9 kg/m(2)] or very obese [BMI > or =35 kg/m(2)]) randomized from 1997-1999 in the SYMPHONY (Sibrafiban vs aspirin to Yield Maximum Protection from ischemic Heart events postacute cOroNary sYndromes) and 2nd SYMPHONY trials, we evaluated the relationships between BMI and 30-day, 90-day, and 1-year mortality and 30-day and 90-day death or myocardial infarction., Results: Increasing BMI was associated with younger age, multiple comorbidities, and greater cardiac medication and procedure use; however, systolic function and coronary disease extent were similar for all BMI categories. Unadjusted Kaplan-Meier mortality estimates were higher for normal-weight patients than for all other BMI groups. After multivariable adjustment, the 30-day mortality hazard ratios (95% confidence interval [CI]) were: overweight, 0.66 (95% CI: 0.47 to 0.94); obese, 0.61 (95% CI: 0.39 to 0.97); very obese, 0.89 (95% CI: 0.48 to 1.64). Adjusted hazard ratios were similar for 90-day and 1-year mortality. There were no statistically significant differences among BMI groups in 30-day and 90-day death or myocardial infarction (unadjusted or adjusted)., Conclusion: Overweight and obese BMI classifications were associated with better intermediate-term survival after acute coronary syndromes than normal weight and very obese, but death or myocardial infarction rates were similar. Further study is required to understand the apparent association of overweight and moderate obesity with better intermediate-term outcomes.