Abstract
Athonian Orthodox fasting (AOF) is characterized by energy- and time-restricted eating (TRE) and is based on the Mediterranean diet. We aimed to investigate the impact of AOF compared to another TRE model on vaspin, omentin, nesfatin, and visfatin levels. We included 25 individuals (mean age 50.3 ± 8.6 years, 24% men) who practiced AOF and abstained from animal products, with the exception of seafood and fish. This group adopted a 12 h eating interval (08.00 to 20.00). In total, 12 participants (mean age 47.7 ± 8.7 years, 33.3% men) who practiced 16:8 TRE (eating from 09:00 to 17:00) and were allowed to consume meat served as the controls. Anthropometric and dietary data and adipokine levels were prospectively collected at three time points: at baseline, after the end of the diets (7 weeks), and 5 weeks after the participants returned to their typical eating habits (12 weeks from baseline). Vaspin levels decreased [795.8 (422.1-1299.4) (baseline) vs. 402.7 (203.8-818.9) (7 weeks) pg/mL, p = 0.002] and omentin levels increased [568.5 (437.7-1196.5) (baseline) vs. 659.0 (555.7-1810.8) (12 weeks) pg/mL, p = 0.001] in the AOF group, while none of the analyzed adipokines changed significantly in the TRE group. The variations observed in vaspin and omentin concentrations in the AOF group were independent of age, sex, changes in anthropometry and fat intake. In conclusion, AOF can significantly reduce vaspin and increase omentin, whose levels are known to increase and decrease, respectively, in obesity and type 2 diabetes. The implications of these findings for cardiometabolic health warrant further investigation.