Effect of Ramadan fasting on some components of metabolic syndrome

Insulin resistance is a feature of a number of clinical disorders including type 2 diabetes, glucose intolerance, obesity, dyslipidemia and hypertension clustering in the so-called metabolic syndrome. The purpose of this study was to evaluate the effect of Ramadan fasting on insulin sensitivity in subjects with metabolic syndrome. In this study 55 males (34.1± 8.9 years) with metabolic syndrome were studied. Blood pressure, waist circumference, body weight, high density lipoprotein (HDL-C), triglyceride, fasting plasma glucose (FPG), fasting blood insulin and insulin resistance indices (QUICKI or quantitative insulin sensitivity check index, HOMA-IR or Homeostasis model assessment of insulin resistance and 1/HOMA-IR) were evaluated before and after 30 days of Ramadan fasting (2 meals at 12 hours intervals). The dietary intake was estimated by 24 h recall before and after fasting. The total daily energy intake was decreased by 56± 33.91 Kcal per day in the fasting period (p = 0.005). 1/HOMA-IR, QUICKI and HDL-C were significantly increased (p = 0.005, p = 0.001 and p = 0.004) and FPG significantly decreased (p < 0.005) after fasting. Simple linear regression analysis demonstrated that HOMA-IR, 1/HOMA-IR and QUICKI were related to waist circumference after intervention (r = 0.458, p < 0.001 r = -0.396, p < 0.05 r = -0.342, p < 0.05). This study showed that combined change in the number and timing of meals and portioning of the entire intake into only 2 meals per day might increase insulin sensitivity in subjects with metabolic syndrome even when the decrease in energy consumption was minimal.