Conclusions
Free-living participants were able to comply with 14 h of daily daytime abstinence from food and drinking for 28 d with only a minor effect on body mass index and without any effects on body composition, glucose metabolism, and cognitive function.
Methods
Ten healthy, lean men were included in a nonrandomized, crossover, intervention study. Testing was performed before a control period of 28 d, as well as before and after 28 d of RIF. Whole-body dual-energy x-ray absorptiometry, magnetic resonance imaging of the abdomen, fitness test, oral glucose tolerance test, and cognitive function tests were performed. As secondary outcome, the participants' physical activity and 72-h glycemic responses were monitored 6 d within each of the periods. Dietary intake, appetite, and mood questionnaires also were assessed.
Results
Comparing Δ differences from testing days; body mass index changes from the control period (Δ mean: 0.2 kg/m2, 95% confidence interval [CI], -2 to 0.5) and the RIF period (Δ mean: -0.3 kg/m2, 95% CI, -0.6 to -0.1) were significantly different (P < 0.05). Secondary outcomes within the RIF period showed an increased area under curve (AUC) for hunger accompanied by a reduced AUC for satiety (both, P < 0.05), less mean steps per day (P < 0.05), and less positive feelings in the afternoon (P < 0.01) compared with the control period. No changes were observed in any of the other evaluated parameters. Conclusions: Free-living participants were able to comply with 14 h of daily daytime abstinence from food and drinking for 28 d with only a minor effect on body mass index and without any effects on body composition, glucose metabolism, and cognitive function.