People who complete a 12-week intermittent fasting program maintain their weight loss for at least one year after stopping the program.
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A 12-week intermittent fasting program results in sustained weight loss maintenance for at least one year following program completion in humans.
Very strong evidence
Randomized trialsOne good-quality study supports this claim.
What the research says
1 study reviewedSupporting (1)
The Effect of 4:3 Intermittent Fasting on Weight Loss at 12 Months
Randomized Controlled TrialHuman2025
People who followed a plan of eating very little on 3 days a week and eating normally on the other 4 days lost more weight and kept it off after a year than people who ate less every day. This suggests intermittent fasting can help people maintain weight loss long-term.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
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When a person eats less on certain days, their body uses stored fat for energy instead of sugar from food. This lowers a hormone called insulin, which tells the body to burn fat and stop feeling hungry. As a result, the person eats less over time and keeps the weight off.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting study
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