Effect of Ramadan Fasting on Weight and Body Composition in Healthy Non-Athlete Adults: A Systematic Review and Meta-Analysis.

Hamish A Fernando, Jessica Zibellini, Rebecca A Harris, Radhika V Seimon, Amanda Sainsbury

Journal: Nutrients 2019;11(2):478

PMID: 30813495

Plain Language Summary

Ramadan is the Islamic tradition of fasting for one month from sunrise to sunset. Generally, Ramadan is known to impact weight. This systematic review and meta-analysis specifically evaluated the effects of Ramadan on both weight and body mass (fat mass and fat-free mass), pre and post fasting, and in the context of there being no attempt to influence physical activity or diet. The meta-analysis was conducted on 70 publications, 90 comparison groups and 2947 participants. Data was also extracted for diverse sub-groups such as overweight/obese, gender and geographical location. The results showed that Ramadan promoted a significant reduction in weight pre and post fasting across all participants, and that the greater the BMI prior to Ramadan fasting, the greater the weight loss. No significant differences were noted between genders. Weight loss was significant in the Middle East + North Africa, South Asia and South East Asia, but not in Westernized countries. Ramadan fasting promoted a transient reduction in fat mass as a percentage of weight, and absolute fat mass, but quickly returned to pre-fasting levels at follow-up 2-5 weeks later. A significant reduction in fat-free mass was also noted but 30% less than total fat mass. There was insufficient data to analysis the possible impact of physical activity. The authors conclude that Ramadan represents an opportunity for promoting weight and fat loss for people with overweight or obesity but requires strategies for long-term maintenance

Abstract

BACKGROUND

Ramadan involves one month of fasting from sunrise to sunset. In this meta-analysis, we aimed to determine the effect of Ramadan fasting on weight and body composition.

METHODS

In May 2018, we searched six databases for publications that measured weight and body composition before and after Ramadan, and that did not attempt to influence physical activity or diet.

RESULTS

Data were collected from 70 publications (90 comparison groups, 2947 participants). There was a significant positive correlation between starting body mass index and weight lost during the fasting period. Consistently, there was a significant reduction in fat percentage between pre-Ramadan and post-Ramadan in people with overweight or obesity (-1.46 (95% confidence interval: -2.57 to -0.35) %, = 0.010), but not in those of normal weight (-0.41 (-1.45 to 0.63) %, = 0.436). Loss of fat-free mass was also significant between pre-Ramadan and post-Ramadan, but was about 30% less than loss of absolute fat mass. At 2⁻5 weeks after the end of Ramadan, there was a return towards, or to, pre-Ramadan measurements in weight and body composition.

CONCLUSIONS

Even with no advice on lifestyle changes, there are consistent-albeit transient-reductions in weight and fat mass with the Ramadan fast, especially in people with overweight or obesity.

Address: Faculty of Medicine and Health, Nutrition, Exercise and Eating Disorders, The Boden Institute of Obesity, The University of Sydney, Charles Perkins Centre, NSW 2006, Australia. [email protected].; Faculty of Medicine and Health, Nutrition, Exercise and Eating Disorders, The Boden Institute of Obesity, The University of Sydney, Charles Perkins Centre, NSW 2006, Australia. [email protected].; Faculty of Medicine and Health, Nutrition, Exercise and Eating Disorders, The Boden Institute of Obesity, The University of Sydney, Charles Perkins Centre, NSW 2006, Australia. [email protected].; Faculty of Medicine and Health, Nutrition, Exercise and Eating Disorders, The Boden Institute of Obesity, The University of Sydney, Charles Perkins Centre, NSW 2006, Australia. [email protected].; Faculty of Medicine and Health, Nutrition, Exercise and Eating Disorders, The Boden Institute of Obesity, The University of Sydney, Charles Perkins Centre, NSW 2006, Australia. [email protected].

DOI: 10.3390/nu11020478