Abstract
Intermittent fasting (IF) has been gaining popularity as a means of losing weight. The Ramadan fast (RF) is a form of IF practiced by millions of adult Muslims globally for a whole lunar month every year. It entails a major shift from normal eating patterns to exclusive nocturnal eating. RF is a state of intermittent liver glycogen depletion and repletion. The earlier (morning) part of the fasting day is marked by dominance of carbohydrate as the main fuel, but lipid becomes more important towards the afternoon and as the time for breaking the fast at sunset (iftar) gets closer. The practice of observing Ramadan fasting is accompanied by changes in sleeping and activity patterns, as well as circadian rhythms of hormones including cortisol, insulin, leptin, ghrelin, growth hormone, prolactin, sex hormones, and adiponectin. Few studies have investigated energy expenditure in the context of RF including resting metabolic rate (RMR) and total energy expenditure (TEE) and found no significant changes with RF. Changes in activity and sleeping patterns however do occur and are different from non-Ramadan days. Weight changes in the context of Ramadan fast are variable and typically modest with wise inter-individual variation. As well as its direct relevance to many religious observers, understanding intermittent fasting may have implications on weight loss strategies with even broader potential implications. This review examines current knowledge on different aspects of energy balance in RF, as a common model to learn from and also map out strategies for healthier outcomes in such settings.
Highlights
Fasting can be defined as the voluntary abstinence from or reduction of some or all food, drink, or both for a period of time lasting typically between 12 h and 3 weeks i.e., in a short term, long term/prolonged or an intermittent pattern [1]
Remained unchanged, while in males, Ramadan fasting resulted in weight loss
In a more recent excellent meta-analysis, Fernando and colleagues showed that the mean weight loss with Ramadan fasting was 1.34 kg and that most of the weight was regained a few weeks post-Ramadan [51]
Summary
Fasting can be defined as the voluntary abstinence from or reduction of some or all food, drink, or both (absolute) for a period of time lasting typically between 12 h and 3 weeks i.e., in a short term, long term/prolonged or an intermittent pattern [1]. In the context of Muslim Ramadan-type fasting, changes in energy intake depend on social, cultural and individual factors and can range from a reduction to an increase in weight [17,18,19]. Whether this is accompanied by changes in energy expenditure is not well-known and merits further exploration for its possible implications in weight loss management strategies in general [20]. Significant group × time interaction revealed reduced body mass and adiposity in FAST, without changing lean mass, whereas CNT subjects remained unchanged. The overall activity patterns remained similar; 1.54 pre-and 1.51 during Ramadan
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call