Interactions between leptin, neuropeptide-Y and insulin with chronic diurnal fasting during Ramadan

Abstract

BackgroundFasting during the month of Ramadan for Muslims is a unique metabolic model that includes abstinence from food and fluid intake during the period from dawn to sunset as well as a reduction in meal frequency and alterations in the sleep-wakefulness cycle. Leptin, neuropeptide-Y and insulin are thought to play an important role in long-term regulation of caloric intake and energy expenditure. However, the long-term changes and interactions between these factors during this pattern of fasting are not known.Subjects and MethodsThe study was conducted on 46 healthy female volunteers (age, 22±2 years; BMI, 25.3±0.7 kg/m2). Anthropometrical measurements, estimation of body fat and fasting serum levels of neuropeptide Y, leptin, insulin and glucose were estimated at baseline (day 1), days 14 and 28 of the month of Ramadan and 2 weeks after Ramadan.ResultsBaseline serum levels of leptin correlated positively with body fat (r=0.87, P=0.0002). Serum leptin levels exhibited a significant increase by approximately 41 % and neuropeptide-Y levels were decreased by 30.4% throughout the month of Ramadan. In addition, a significant correlation (r=0.63, P=0.0001) was found between changes in serum leptin and serum insulin. However, changes in serum neuropeptide-Y levels did not correlate with those of leptin or insulinConclusionsLong-term fasting with interrupted nocturnal eating is associated with significant elevations in serum leptin and insulin and reduction in serum neuropeptide-Y. The changes in serum leptin are likely mediated through insulin. However, changes in neuropeptide-Y appears to be mediated independently of leptin or insulin during this type of fasting

Effect of Prolonged Intermittent Fasting in Ramadan on Biochemical and Inflammatory Parameters of Healthy Men

“…Moreover, regular sleeping patterns are changed during Ramadan. This affects levels of leptin, neuropeptide-Y, insulin, melatonin, steroid hormones, pituitary hormones and thyroid hormones that have essential roles in regulation of energy balance and glucose metabolism [45][46]. The decrease in FBS and HOMA index could be related to the above factors.…”

Islamic fasting and weight loss: a systematic review and meta-analysis

“…Changes in sleeping hours might change the serum level of leptin, insulin and cortisol; these factors could affect daily energy consumption (38) and indirectly may explain some of the body weight variation during and after Ramadan. Some authors suggest that the body weight changes could be attributed to variations of fluid intake (11,54) . Dehydration certainly occurs during the fasting hours.…”

Investigating the Effect of Fasting on Appetite Regulatory Hormones in Thin and Obese Females

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