Can skipping meals 3 days a week help you lose more weight than eating less every day?
The Effect of 4:3 Intermittent Fasting on Weight Loss at 12 Months
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
People who ate very little on 3 random days a week and ate normally the other 4 days lost more weight than people who ate a little less every single day — even though both groups were supposed to cut the same total calories per week.
Surprising Findings
Both groups fell short of their targeted 34.3% weekly energy deficit, yet the 4:3 group still lost significantly more weight.
It’s assumed that hitting exact calorie targets is essential for weight loss — but here, the group that didn’t even meet the target still outperformed the group that tried harder to hit it.
Practical Takeaways
Try 4:3 intermittent fasting: restrict calories to 20% of your normal intake on 3 nonconsecutive days per week, and eat normally the other 4 days — no tracking needed on non-fast days.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
People who ate very little on 3 random days a week and ate normally the other 4 days lost more weight than people who ate a little less every single day — even though both groups were supposed to cut the same total calories per week.
Surprising Findings
Both groups fell short of their targeted 34.3% weekly energy deficit, yet the 4:3 group still lost significantly more weight.
It’s assumed that hitting exact calorie targets is essential for weight loss — but here, the group that didn’t even meet the target still outperformed the group that tried harder to hit it.
Practical Takeaways
Try 4:3 intermittent fasting: restrict calories to 20% of your normal intake on 3 nonconsecutive days per week, and eat normally the other 4 days — no tracking needed on non-fast days.
Publication
Journal
Annals of internal medicine
Year
2025
Authors
V. Catenacci, Danielle M. Ostendorf, Zhaoxing Pan, Laura K Kaizer, Seth A. Creasy, A. Zaman, A. Caldwell, Jared H Dahle, Bryan Swanson, Matthew J Breit, Kristen Bing, Liza T Wayland, Shelby L Panter, Jared J Scorsone, D. Bessesen, Paul S. MacLean, Edward L. Melanson
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Claims (4)
In a weight management program, adults following a 4:3 intermittent fasting schedule were less likely to drop out after 12 months than those following a daily calorie-restricted diet.
Among adults with overweight or obesity who received behavioral support, those who followed a 4:3 intermittent fasting schedule showed the same increase in moderate-to-vigorous physical activity over 12 months as those who did not follow this eating pattern.
In a 12-month weight loss program for adults with overweight or obesity, a pattern of eating that involves severe calorie restriction on three nonconsecutive days per week led to slightly more weight loss and a higher rate of achieving at least 5% weight loss compared to daily moderate calorie restriction.
Among adults with overweight or obesity who received behavioral support, those following a 4:3 intermittent fasting schedule reduced their calorie intake more over 12 months than those following a daily calorie restriction plan, with average reductions of 9.75% versus 5.64%.