BACKGROUND: The aim of this study was to determine how Ramadan fasting (RF) affected the recently described new obesity indices [visceral adiposity index (VAI), waist circumference to height ratio (WHtR), body adiposity index (BAI)], and serum concentration of apelin-13 (RF) in healthy adult men.

MATERIAL AND METHODS: For this purpose, 42 healthy adult men were selected. Anthropometric parameters were measured and a sample of venous blood was obtained for biochemical assays on the first and last days of Ramadan. When all subjects were evaluated, all anthropometric parameters changed except VAI. Serum apelin-13, triglyceride (TG), HDL-cholesterol (HDL-C), and insulin levels did not change. When patients were divided into 3 groups according to body mass index (BMI), BAI decreased in normal-weight subjects and WHtR decreased in other groups, but VAI and apelin-13 did not change in any groups.

RESULTS: We demonstrate for the first time that while some anthropometric parameters changed, VAI and serum apelin-13 levels did not change with RF. BMI, waist circumference (WC), TG, and HDL-C were evaluated together in calculation of VAI. TG, VAI, and HDL-C remained unchanged by RF. Even if body weight (BW) and BMI decreased, apelin-13 was not affected by RF. The data on serum apelin-13 may have been influenced by the small-percentage decrease in BW, as well as insignificant improvements in metabolic parameters such as lipid profiles, glucose, and insulin.

CONCLUSIONS: We found that Ramadan fasting in healthy adult men was associated with significant decreases in BW, BMI, WHtR, and BAI, but we found no significant changes in VAI and serum apelin-13 concentrations.

Keywords: Intra-Abdominal Fat, Adiposity - physiology, Fasting, Body Mass Index, Cholesterol, HDL - blood, Fasting - blood, Intercellular Signaling Peptides and Proteins - blood, Intra-Abdominal Fat - metabolism, Islam, Turkey, Waist-Height Ratio