Sex differences in energy homeostatis following a diet relatively high in protein exchanged with carbohydrate, assessed in a respiration chamber in humans

ContextObesity prevalence is generally higher in women than in men, and a paucity of research with sex-specific approaches exists. The question arises whether current weight loss programmes, largely developed and tested on women, are appropriate for men.ObjectiveInvestigate 24 h energy metabolism, satiety and related hormones during a diet relatively high in protein (HP), exchanged with carbohydrate compared to an adequate-protein (AP) diet, in a respiration chamber in men, in comparison with previous outcomes in women.DesignTen healthy males (BMI: 22.5 ± 1.6 kg/m2, age: 25 ± 3.5 y) were fed in energy balance with an AP (10/60/30% of energy of protein/carbohydrate/fat) or a HP (30/40/30% of energy of protein/carbohydrate/fat) diet in a randomized cross-over design.ResultsDuring the HP diet, 24 h Energy Expenditure (10.5 ± 0.5 vs 10.0 ± 0.5 MJ/d; p < 0.05), Sleeping Energy Expenditure (7.1 ± 0.3 vs 6.9 ± 0.2 MJ/d; p < 0.05), protein balance (0.5 ± 0.02 vs 0.0 ± 0.01 MJ/d; p < 0.05), satiety (AUC) p < 0.05, and plasma GLP-1 concentrations (42 ± 23 vs 28 ± 16 AUC; p < 0.005) were significantly higher and 24 h RQ (0.80 vs 0.85; p < 0.01), fat balance (− 0.85 ±0.03 vs 0.05 vs 0.03 MJ/d; p < 0.01) and hunger (AUC) p < 0.05, were significantly lower. Comparisons reveal a stronger reaction in men in energy expenditure and substrate oxidation, whereas satiety reacted stronger in the women.ConclusionsEffects of a diet relatively high in protein exchanged with carbohydrate, vs an adequate protein diet are a stronger increased energy expenditure, fat oxidation, protein anabolism in men, and a stronger increased satiety in women, thereby creating sex-specific conditions for long-term use for body-weight management.