Health benefits and consequences of the Eastern Orthodox fasting in monks of Mount Athos: a cross-sectional study

BACKGROUND/OBJECTIVES: Greek Orthodox fasting (OF), which involves 180-200 days of fasting per year, is dictated by the Christian Orthodox religion. For the first time, this cross-sectional study examines the characteristics and the effects of OF on anthropometry, cardiometabolic markers and calcium homeostasis in Athonian monks (AMs). SUBJECTS/METHODS: Daily intakes of energy, macro-and micronutrients of a day during a weekend of Nativity Fast, defined as non-restrictive day (NRD), and a weekday during Great Lent, labeled as restrictive day (RD) were recorded. RESULTS: The daily energy intake of 70 AM (age = 38.8 +/- 9.7 years) was low during both RD and NRD (1265.9 +/- 84.5 vs 1660 +/- 81 kcal, respectively, P < 0.001). Paired samples t-test showed statistically significant difference between daily intakes in RD and NRD: carbohydrates (159.6 +/- 21.8 vs 294.3 +/- 23.4 g, P < 0.0001) and saturated fat (12.7 +/- 0.0 vs 16.4 +/- 0.0 g, P < 0.0001) were lower, whereas protein (89.2 +/- 1.3 vs 72.35 +/- 1.3 g, P < 0.001) was higher during RD. A subsample of 50 monks (age = 38.7 +/- 10.6 years) formed a study cohort for cardiometabolic and calcium homeostasis assessment. Body weight (74.3 +/- 12.9 kg) and body mass index (BMI; 23.8 +/- 4.1 kg/m(2)) were independent of level of physical activity. Optimal profiles for lipid and glucose parameters (total cholesterol: 183.4 +/- 41.7 mg/dl, LDL: 120.6 +/- 37.6 mg/dl, triglycerides: 72.2 +/- 31.3 mg/dl, HDL: 48.5 +/- 14.2 mg/dl and homeostasis model assessment of insulin resistance (HOMA-IR) 1.02 +/- 0.40) were found. Profound hypovitaminosis D (8.8 +/- 6.2 ng/ml), high parathyroid hormone (PTH): 115.5 +/- 48.0 pg/ml with normal serum calcium levels (8.9 +/- 3.2 mg/dl) was observed. CONCLUSIONS: Unaffected by variation in lifestyle factors, the results of this unique study offers clear evidence for the health benefits of the strict Athonian OF through optimal lipid and glucose homeostasis.