London: According to an extensive new analysis published in The BMJ, alternate-day fasting may be more effective for weight loss than traditional daily calorie restriction. Researchers reviewed 99 clinical trials involving over 6,500 adults to compare diet strategies and their effects on body weight and health.
The study found intermittent fasting, especially alternate-day fasting, showed slightly better weight loss results than continuous energy restriction and other fasting methods like time-restricted eating and whole-day fasting. People who followed alternate-day fasting lost about 1.3 kg more than those who used daily calorie restriction, though the difference did not meet the clinical threshold of 2 kg weight loss for obese individuals.
Alternate-day fasting also helped lower total cholesterol and “bad” LDL cholesterol compared to time-restricted eating. However, none of the diets showed a clear benefit for improving blood sugar or “good” HDL cholesterol levels.
The study participants were mostly women around 45 years old, with an average BMI of 31. Nearly 90% had other health issues. Trial durations ranged from 3 to 52 weeks, but longer trials were more likely to show sustained benefits.
The researchers noted limitations, including the varying trial quality of some studies and small sample sizes. Still, they say their review is one of the first to combine direct and indirect evidence across all major dietary approaches.
In a related editorial, experts from Colombia emphasised that alternate-day fasting should not replace other diet methods but should be considered an added option in a personalised nutrition plan. They noted that factors like professional guidance, planning, and food quality during non-fasting periods also play a key role in success.
The study suggests that intermittent fasting—particularly alternate-day fasting—offers a promising and flexible strategy for weight loss and improving heart health. However, longer studies are still needed to confirm these results.
