Intermittent fasting not more effective than conventional diets, Brazil study shows

A systematic review of 22 clinical trials involving nearly 2,000 overweight or obese adults, published in the Cochrane Library, concluded that intermittent fasting does not lead to greater weight loss than traditional calorie‑restricted diets. Participants following fasting protocols lost an average of about 300 g more than control groups, a difference that was not statistically significant. Researchers noted that while intermittent fasting can produce metabolic changes such as improved insulin sensitivity and increased fat oxidation, these do not translate into clinically relevant advantages over standard diets. The authors emphasized that the choice of eating pattern should depend on individual adherence and sustainability rather than presumed metabolic benefits.

Potential side effects reported include fatigue, dizziness, excessive hunger, headaches, nausea, and hypoglycemia, especially in people with a history of eating disorders or those on glucose‑lowering medication. Experts advise that patients consider personal lifestyle and seek professional guidance before adopting fasting regimes.