Possible metabolic impact of Ramadan fasting in healthy men

Abstract

Background/aim: Insulin sensitivity and β-cell function during Ramadan fasting in healthy male subjects have not been investigated so far. We assessed the changes of these and other metabolic parameters to judge the potential metabolic benefits of Ramadan fasting.Materials and methods: Twenty-four healthy males of Turkish origin living in Germany, with normal glucose tolerance, participated in this study during Ramadan of 2009; 19 who completed fasting were analyzed. Blood was drawn at sunset after a period of fasting lasting approximately 15 h on days 0, 16, and 30 of Ramadan, as well as 7 and 28 days later. Insulin sensitivity (Homeostasis Model Assessment, HOMA), β-cell function, and other parameters were assessed.Results: Ramadan fasting was associated with a significant reduction (-) or increment (+) for the following variables: insulin sensitivity (-20%; P = 0.04), β-cell function (+10%; P = 0.049), high-density lipoprotein cholesterol (-23%; P = 0.0003), low-density lipoprotein cholesterol (+14%; P = 0.007), nonesterified fatty acids (-62%; P < 0.0001), resistin (-20%; P = 0.01), adiponectin (+16%; P = 0.003), and glucagon (-21%; P = 0.01). C-peptide, insulin, leptin, triglyceride, and very low-density lipoprotein cholesterol concentrations were not significantly changed. Conclusion:Ramadan fasting is associated with transiently impaired insulin sensitivity, compensated for by an increased β-cell function. However, the pattern of insulin resistance-mediating adipocytokines suggests a potentially beneficial metabolic effect of Ramadan fasting.

Impact of Ramadan diurnal intermittent fasting on the metabolic syndrome components in healthy, non-athletic Muslim people aged over 15 years: a systematic review and meta-analysis

“…The presence of the MetS has also been associated with lower plasma adiponectin levels (117) , indicating adipose tissue dysfunction and a two-to four-times increased risk for developing CVD and type 2 diabetes (118) . Similarly, several reports have indicated RDIF was associated with variable increments in adiponectin levels in fasting people (119)(120)(121) . Recently, we found that RDIF was associated with significant reduction in visceral fat surface area (measured by MRI) in fifty-seven overweight/obese participants, concomitant with significant reductions proinflammatory cytokines (IL-6 and TNF-α), and a significant increase in the anti-inflammatory cytokine IL-10 (122) .…”

Chronobesity: role of the circadian system in the obesity epidemic

“…Muslims markedly change their dietary patterns during the holy month of Ramadan, when they decide to fast from dawn to dusk. Several studies investigating the possible health and metabolic impact of this type of fasting have described beneficial effects on body weight, blood glucose concentration and lipid profiles . However, their results were highly variable because of differences in gender, age, dietary habits and ethnicity.…”

Adaptive Effects of Endocrine Hormones on Metabolism of Macronutrients during Fasting and Starvation: A Scoping Review

“…It has been suggested that the synthesis of very low-density lipoprotein (VLDL), a triacylglycerol-rich particle, is increased in hepatocytes in response to reduced insulin action under fasting conditions [ 76 ]. It is suggested that Ramadan fasting results in a transient reduction in insulin sensitivity, which is compensated by an improved β-cell function with no significant change in glucose concentrations [ 37 ]. It has been reported that increased levels of glucagon and low levels of insulin augment lipolysis and ketogenesis [ 26 ].…”