Effects of orthodox religious fasting versus combined energy and time restricted eating on body weight, lipid concentrations and glycaemic profile

Abstract

For seven weeks, 37 overweight adults followed a hypocaloric diet based on Orthodox Fasting (OF). A hypocaloric, time restricted eating (TRE) plan (eating between 08:00 to 16:00 h, water fasting from 16:00 to 08:00 h) was followed by 23 Body Mass Index (BMI)-matched participants. Anthropometric, glycaemic and inflammation markers and serum lipids were assessed before and after the diets. Both OF and TRE groups demonstrated reductions in BMI (28.54 ± 5.45 vs 27.20 ± 5.10 kg/m², p < 0.001 and 26.40 ± 4.11 vs 25.81 ± 3.78 kg/m² p = 0.001, respectively). Following the intervention, the OF group presented lower concentrations of total and low-density lipoprotein-cholesterol, compared with the pre-fasting values (178.40 ± 34.14 vs 197.17 ± 34.30 mg/dl, p < 0.001 and 105.89 ± 28.08 vs 122.37 ± 29.70 mg/dl, p < 0.001, respectively). Neither group manifested significant differences in glycaemic and inflammatory parameters. Our findings suggest that OF has superior lipid lowering effects than the TRE pattern.

Keywords: Orthodox fasting; cardiometabolic markers; insulin resistance; intermittent fasting; lipids; time restricted eating.