Abstract This study aimed to evaluate the influence of different intermittent fasting regimens on metabolic parameters in healthy rats and compare them to caloric restriction. A total of 50 adult male Wistar rats (± 90 days old) were randomised into 5 groups: control group (CON); caloric restriction group (CR); time-restricted feeding group (TRF); alternate-day fasting (ADF) group; and alternate-day modified fasting group (ADMF). ADF and ADMF stood out for improving the metabolic parameters in healthy rats by presenting improvements in glucose parameters, greatest weight loss (ADF vs . CON: -16.50±6.16 g; effect size = -5.34; 95% CI: -7.05, -3.04; p < 0.001; ADMF vs . CON: - 21.88±6.66 g; effect size = -5.83; 95% CI: -7.66, -3.36; p < 0.001), and higher HDL (ADF vs . CON: 141.50±10.17 mg/dL; effect size = 3.03; 95% CI: 1.01, 4.45; p<0.001; ADMF vs . CON: 133.10±5.94 mg/dL; effect size = 3.37; 95% CI: 1.22, 4.86; p=0.004). Additionally, ADMF presented a smaller adipocyte area among the fasting regimens (13.92±2.06 area/µm 2 ; effect size = -4.20; 95% CI: -5.45, -2.66; p<0.001 vs . CON), in addition to presenting muscle fibre hypertrophy (71.20±5.16 area/µm 2 ; effect size = 2.93; 95% CI: 1.57, 4.05; p<0.001 vs . CON), followed by ADF (adipocyte area: 19.25±0.87 area/µm 2 ; effect size = -2.19; 95% CI: -3.12, -1.12; p=0.003 vs . CON; muscle fibre: 53.80±6.61 area/µm 2 ; effect size = 2.93; 95% CI: 1.57,4.05; p=0.566 vs . ADMF). The ADF and ADMF groups were more effective among the intermittent fasting regimens analysed in promoting improvements in metabolic parameters in healthy rats.
Soares et al. (Fri,) studied this question.