Abstract
AIMS: We hypothesized that if we control for lifestyle changes during Ramadan, Ramadan Islamic intermittent fasting (IF) reduces oxidative stress. This study was conducted to examine the effect of Islamic IF during and outside of Ramadan on the circadian changes in lipid peroxidation marker malondialdehyde (MDA) during and outside while controlling for potential confounders. METHODS: Serum MDA concentration was measured in eight healthy male volunteers at baseline (BL), after fasting for 1 week before Ramadan (BL fasting), and during Ramadan. Blood samples were drawn at 22:00, 02:00, 04:00, 06:00, and 11:00. The participants were admitted to the sleep laboratory and monitored for 24 h on the day of the measurements. In the laboratory, each participant received meals of fixed compositions and caloric contents based on their ideal body weights. Light exposure, physical activity, and total sleep duration were uniformly maintained during the three study periods. RESULTS: The participants had a mean age of 26.6 ± 4.9 years and a mean body mass index of 23.7 ± 3.5 kg/m(2). No significant changes were observed in MDA levels and blood glucose during BL, BL fasting, or Ramadan. CONCLUSION: In this pilot study, under conditions of fixed sleep-wake schedules and caloric intake, Ramadan IF does not alter serum MDA levels in healthy subjects. Larger studies are needed to confirm these findings.