The Study
Intermittent fasting strategies and their effects on body weight and other cardiometabolic risk factors: systematic review and network meta-analysis of randomised clinical trials
This study looked at lots of people who tried different diets and compared what happened to them in carefully run experiments. It tells us that some diets help people lose a little weight, but it doesn't prove one diet is way better than another — just a tiny bit better in some cases.
Analysis score
Maximum 100 for a systematic review with meta-analysis.
Where the score came from
This study looked at different ways people try to lose weight by skipping meals or eating only at certain times, and compared them to just eating fewer calories every day.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 553 / 100
Quality score
The highest quality evidence. Systematic reviews and meta-analyses that pool randomized controlled trials, giving the most reliable summary of experimental evidence.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Losing 1.3 kg is a small amount — not enough to be considered clinically meaningful for most people.
- 2All methods worked similarly in the long run.
- 3All fasting methods and eating less helped people lose weight compared to eating without limits.
- 4Alternate day fasting helped people lose a little more weight (about 1.3 kg) than eating less every day.
- 5Other fasting methods didn't help more than eating less.
- 6After 6 months, the differences disappeared.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
The BMJ
Year
2025
Authors
Zhila Semnani-Azad, T. Khan, L. Chiavaroli, Victoria Chen, H. Bhatt, Alisia Chen, Nicholas Chiang, J. Oguntala, S. Kabisch, David Lau, S. Wharton, Arya M. Sharma, L. Harris, Lawrence A. Leiter, James O. Hill, Frank B. Hu, Michael EJ Lean, H. Kahleová, Dario Rahelić, J. Salas‐Salvadó, Cyril Kendall, J. Sievenpiper
Related Content
Claims (5)
In adults with overweight or obesity, alternate day fasting leads to a small but measurable weight loss of about 1.29 kg more than continuous calorie restriction over the same period, without greater improvements in other metabolic health markers.
In adults with overweight or obesity, intermittent fasting methods such as alternate day fasting, time-restricted eating, and whole-day fasting result in a weight loss of 1.7 to 3.4 kg compared to eating without restrictions, but this weight loss is not greater than what is achieved with continuous calorie restriction.
In adults with overweight or obesity, alternate day fasting lowers total cholesterol, triglycerides, and non-HDL cholesterol more than time-restricted eating.
In adults with overweight or obesity, time-restricted eating and whole-day fasting do not lead to better levels of HbA1c, fasting glucose, or HDL cholesterol than simply reducing calories consistently throughout the day.
After 24 weeks, intermittent fasting and daily calorie restriction lead to the same amount of weight loss compared to eating without restrictions, and neither method stays superior to the other over the long term.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.