BACKGROUND: Little is known about the effects of short-term caloric restriction (CR) and overfeeding (OF) on glucose homeostasis in healthy lean individuals. In addition, it remains unclear whether the effects of CR and OF are reversed by a complementary feeding period. METHODS: Ten healthy men participated in two cycles of controlled 7-day periods of CR and refeeding (RF; protocol A), and OF and CR (protocol B) at ±60% energy requirement. At baseline, insulin sensitivity (IS) was assessed by euglycemic clamp (M). Before and during each feeding cycle, fasting and oral glucose tolerance test-derived indices were used to estimate glucose tolerance, IS and glucose-stimulated insulin secretion. RESULTS: Clamp tests revealed normal IS at baseline (M-values 9.4±2.1 mg kg⁻¹ min⁻¹, coefficient of variation (CV)(inter) 22%). M-values were significantly correlated with indices of IS. In protocol A, CR-induced weight loss (-3.0±0.4 kg) was associated with an increase in fasting IS. Postprandial IS and glucose-stimulated insulin secretion remained unchanged, but glucose tolerance decreased. RF decreased fasting and postprandial IS at increased glucose-stimulated insulin secretion. In protocol B, OF significantly increased the body weight (+1.6±0.9 kg). Concomitantly, fasting and postprandial IS decreased at increased glucose-stimulated insulin secretion. Subsequent CR reversed these effects. Inter-individual variability in indices of glucose metabolism was high with coefficients of variation ranging from 9 to 59%. CONCLUSION: Significant changes in glucose metabolism are evident within 7-day periods of controlled OF and underfeeding. Although IS was impaired at the end of the CR-RF cycle, IS was normalized after the OF-CR cycle. At different feeding regimens, homeostatic responses of glucose metabolism were highly variable.
BACKGROUND: Little is known about the effects of short-term caloric restriction (CR) and overfeeding (OF) on glucose homeostasis in healthy lean individuals. In addition, it remains unclear whether the effects of CR and OF are reversed by a complementary feeding period. METHODS: Ten healthy men participated in two cycles of controlled 7-day periods of CR and refeeding (RF; protocol A), and OF and CR (protocol B) at ±60% energy requirement. At baseline, insulin sensitivity (IS) was assessed by euglycemic clamp (M). Before and during each feeding cycle, fasting and oral glucose tolerance test-derived indices were used to estimate glucose tolerance, IS and glucose-stimulated insulin secretion. RESULTS: Clamp tests revealed normal IS at baseline (M-values 9.4±2.1 mg kg⁻¹ min⁻¹, coefficient of variation (CV)(inter) 22%). M-values were significantly correlated with indices of IS. In protocol A, CR-induced weight loss (-3.0±0.4 kg) was associated with an increase in fasting IS. Postprandial IS and glucose-stimulated insulin secretion remained unchanged, but glucose tolerance decreased. RF decreased fasting and postprandial IS at increased glucose-stimulated insulin secretion. In protocol B, OF significantly increased the body weight (+1.6±0.9 kg). Concomitantly, fasting and postprandial IS decreased at increased glucose-stimulated insulin secretion. Subsequent CR reversed these effects. Inter-individual variability in indices of glucose metabolism was high with coefficients of variation ranging from 9 to 59%. CONCLUSION: Significant changes in glucose metabolism are evident within 7-day periods of controlled OF and underfeeding. Although IS was impaired at the end of the CR-RF cycle, IS was normalized after the OF-CR cycle. At different feeding regimens, homeostatic responses of glucose metabolism were highly variable.
Authors: Kevin D Hall; Alexis Ayuketah; Robert Brychta; Hongyi Cai; Thomas Cassimatis; Kong Y Chen; Stephanie T Chung; Elise Costa; Amber Courville; Valerie Darcey; Laura A Fletcher; Ciaran G Forde; Ahmed M Gharib; Juen Guo; Rebecca Howard; Paule V Joseph; Suzanne McGehee; Ronald Ouwerkerk; Klaudia Raisinger; Irene Rozga; Michael Stagliano; Mary Walter; Peter J Walter; Shanna Yang; Megan Zhou Journal: Cell Metab Date: 2019-05-16 Impact factor: 27.287
Authors: N Turner; G M Kowalski; S J Leslie; S Risis; C Yang; R S Lee-Young; J R Babb; P J Meikle; G I Lancaster; D C Henstridge; P J White; E W Kraegen; A Marette; G J Cooney; M A Febbraio; C R Bruce Journal: Diabetologia Date: 2013-04-26 Impact factor: 10.122
Authors: Faidon Magkos; Gordon I Smith; Dominic N Reeds; Adewole Okunade; Bruce W Patterson; Bettina Mittendorfer Journal: Obesity (Silver Spring) Date: 2013-09-10 Impact factor: 5.002