RESUMEN

Weight loss intervention is the principal non-pharmacological method for prevention and treatment of type 2 diabetes. However, little is known whether it influences insulin sensitivity directly or via its anti-inflammatory effect. The aim of this study was to assess the independent role of changes in inflammation status and weight loss on insulin sensitivity in this population.Overweight and obese nondiabetic participants without co-morbidities underwent a one-year weight loss intervention focused on caloric restriction and behavioral support. Markers of inflammation, body composition, anthropometric para-meters, and insulin sensitivity were recorded at baseline, 6, and 12 months. Insulin sensitivity was assessed with frequently sampled intravenous glucose tolerance test and Minimal Model. Twenty-eight participants (F: 15, M: 13, age 39±5 years, BMI 33.2±4.6 kg/m(2)) completed the study, achieving 9.4±6.9% weight loss, which was predominantly fat mass (7.7±5.6 kg, p<0.0001). Dietary intervention resulted in significant decrease in leptin, leptin-to-adiponectin ratio, hs-CRP, and IL-6 (all p<0.02), and improvement in HOMA-IR and Insulin Sensitivity Index (SI) (both p<0.001). In response to weight loss IL-1ß, IL-2, leptin, and resistin were significantly associated with insulin, sensitivity, whereas sICAM-1 had only marginal additive effect. Moderate weight loss in otherwise healthy overweight and obese individuals resulted in an improvement in insulin sensitivity and in the overall inflammation state; the latter played only a minimal independent role in modulating insulin sensitivity.

Asunto(s)

Inflamación/terapia , Resistencia a la Insulina/fisiología , Obesidad/dietoterapia , Sobrepeso/dietoterapia , Pérdida de Peso/fisiología , Adulto , Glucemia/análisis , Composición Corporal , Índice de Masa Corporal , Proteína C-Reactiva/análisis , Restricción Calórica , Dieta , Femenino , Humanos , Interleucina-6/sangre , Leptina/sangre , Lípidos/sangre , Masculino , Persona de Mediana Edad , National Institutes of Health (U.S.) , Estudios Prospectivos , Estados Unidos

RESUMEN

OBJECTIVE: Obesity in the United States is highly prevalent, approaching 60% for black women. We investigated whether nutrition education sessions at the work place added to internet-based wellness information and exercise resources would facilitate weight and fat mass loss in a racially diverse population of overweight female employees. METHODS: A total of 199 (average body mass index 33.9±6.3 kg m(-2)) nondiabetic women (57% black) at our institution were randomized to a 6-month program of either internet-based wellness information (WI) combined with dietitian-led nutrition education group sessions (GS) weekly for 3 months and then monthly with shift in emphasis to weight loss maintenance (n=99) or to WI alone (n=100). All were given access to exercise rooms convenient to their work site. Fat mass was measured by dual-energy X-ray absorptiometry. RESULTS: WI+GS subjects lost more weight than WI subjects at 3 months (-2.2±2.8 vs -1.0±3.0 kg, P>0.001). Weight (-2.7±3.9 vs -2.0±3.9 kg) and fat mass (-2.2±3.1 vs -1.7±3.7 kg) loss at 6 months was significant for WI+GS and WI groups (both P<0.001), but without significant difference between groups (both P>0.10); 27% of the WI+GS group achieved 5% loss of initial weight as did 18% of the WI group (P=0.180). Blacks and whites similarly completed the study (67 vs 74%, P=0.303), lost weight (-1.8±3.4 vs -3.3±5.2 kg, P=0.255) and fat mass (-1.6±2.7 vs -2.5±4.3 kg, P=0.532), and achieved 5% loss of initial weight (21 vs 32%, P=0.189), irrespective of group assignment. CONCLUSION: Overweight women provided with internet-based wellness information and exercise resources at the work site lost weight and fat mass, with similar achievement by black and white women. Additional weight loss benefit of nutrition education sessions, apparent at 3 months, was lost by 6 months and may require special emphasis on subjects who fail to achieve weight loss goals to show continued value.

RESUMEN

BACKGROUND: Short sleep and weight gain are inversely related. Sleep deprivation acutely increases food intake but little is known about eating behavior in chronically sleep-deprived, obese individuals. OBJECTIVE: To characterize the relationship between sleep, food intake and alcohol consumption under free-living conditions in obese, chronically sleep-deprived individuals. DESIGN: Cross-sectional study of a cohort of obese men and premenopausal women. SUBJECTS: A total of 118 obese subjects (age: 40.3±6.7 years; 91 females/27 males; body mass index 38.7±6.4 kg m(-2)). MEASUREMENTS: Energy, macronutrient, alcohol and caffeine intake assessed by 3-day food records. Sleep duration estimated by actigraphy. Respiratory disturbance index assessed by a portable device. RESULTS: SUBJECTS slept 360.7±50.2 min per night and had a total energy intake of 2279.1±689 kcal per day. Sleep duration and energy intake were inversely related (r=-0.230, P=0.015). By extrapolation, each 30-min deficit per day in sleep duration would translate to an ∼83 kcal per day increase in energy intake. In addition, sleep apnea was associated with a shift from carbohydrate to fat intake. Alcohol intake in subjects consuming >3.5 g of alcohol per day (N=41) was inversely related to sleep duration (r=-0.472, P=0.002). CONCLUSIONS: Shorter sleep duration and obstructive sleep apnea are associated with higher energy, fat and alcohol intakes in obese individuals. The importance of this study relies on the population studied, obese subjects with chronic sleep deprivation. These novel findings apply to the large segment of the US population who are obese and sleep-deprived.