Research

Energy balance

Ramadan fasting induces a transient reduction in body weight and fat mass in healthy non-athlete adults, with effects being more pronounced in individuals with overweight or obesity and reversing within 2-5 weeks post-fast.

If you fast during Ramadan, expect to lose about 1.3 kg of weight and some fat by the end of the month, especially if you are overweight. This loss is not permanent; you will likely regain the weight within a month after fasting ends. To maintain any fat loss, you must manage your eating habits during the non-fasting hours (iftar/suhoor) to avoid overcompensating.

GoodQualifiesHIGH confidence
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.
Hamish A. Fernando et al. · Nutrients · 2019

Why this rating

Systematic review and meta-analysis of 70 publications with 2947 participants provides high-level evidence, though heterogeneity was noted.

Source

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

Hamish A. Fernando et al. · Nutrients · 2019

DOI 10.3390/nu11020478

Meta-analysis · 70 studiesCited 244×
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DOI resolved against Crossref · corpus check 2026-06-10

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