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Does fasting actually work?
Yes for weight loss, and no better than calorie restriction when the calories are matched.
Ffostio cyfnodol, wedi'i farnu ar y treialon ar hap
Mae ffostio'n gweithio ar gyfer colli pwysau. Y cwestiwn diddorol yw pam — ac mae'r treialon gorau'n awgrymu bod yr ateb yn llai cyffrous na'r drafodaeth.
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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.
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.
Darllen cysylltiedig
GLP-1 Evidence
What the trials actually show about semaglutide, tirzepatide and the rest of the GLP-1 class.
Metabolism Review
Energy expenditure, insulin resistance and metabolic adaptation, without the folklore.
Weight Loss Evidence
Diets, drugs, behaviour and maintenance — ranked by the strength of the evidence behind them.
Sleep Evidence
Sleep, circadian rhythm and the wearables that claim to measure both.
Cafodd y dudalen hon ei thrawsgrifiad yn awtomatig o Saesneg. Mae'r dyfyniadau a'r rhifau heb newid. Darllenwch y gwreiddiol Saesneg os yw unrhyw beth yn darllen yn rhy ddieithr. Darllenwch y gwreiddiol Saesneg