Article
Ramadan fasting and health: what the evidence says
Ramadan is the largest natural experiment in fasting. What meal-timing and metabolic studies say about weight, glucose, sleep and who should take care.
Intermittent fasting, judged on the randomised trials
Fasting works for weight loss. The interesting question is why — and the best trials suggest the answer is less exciting than the discourse.
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The one-paragraph summary
Intermittent fasting produces weight loss. In head-to-head trials against ordinary calorie restriction, it produces roughly the same weight loss. That makes fasting a useful way to eat less rather than a metabolic trick — which is good news if you find it easier than counting, and irrelevant if you do not.
Start here
Does fasting actually work?
Yes for weight loss, and no better than calorie restriction when the calories are matched.
Protocol
Time-restricted eating and 16:8
The most popular protocol, and the one with the most disappointing controlled trials.
Protocol
5:2 and alternate-day fasting
Larger effects than 16:8 in the comparative data, and much harder to sustain.
Circadian
Does when you eat matter?
This is where fasting research is genuinely interesting. Late eating measurably changes energy expenditure.
Mechanism
The autophagy claims
Real biology, wildly overstated in humans. What has actually been measured, and at what fasting length.
Performance
Training fasted
Performance effects are small and depend heavily on what you are asking your body to do.
Metabolic
Blood sugar, insulin and lipids
Where fasting moves markers, and where the movement disappears once weight loss is accounted for.
Safety
Who should not fast
Pregnancy, type 1 diabetes, insulin-treated type 2, eating disorder history, and several medications.
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