Fasting protocols
16:8 overview, autophagy research, electrolytes, women's hormone considerations, refeeds.
If you only read one
16:8 intermittent fasting: what the research currently shows
Time-restricted eating with a 16-hour overnight fast and 8-hour feeding window. What the human trials report on weight, metabolic markers, and the gaps that remain.
Grade B · 2 min read · Last reviewed 2026-05-17
16:8 intermittent fasting: what the research currently shows
Evidence BTime-restricted eating with a 16-hour overnight fast and 8-hour feeding window. What the human trials report on weight, metabolic markers, and the gaps that remain.
2 min read · Last reviewed 2026-05-17
The 5:2 method: what the trials report
Evidence BTwo non-consecutive 'fast' days of ~500–600 kcal per week, with normal eating on the other five. What the trial evidence shows on weight, glucose, and lipids — and how it compares to daily 16:8.
3 min read · Last reviewed 2026-05-19
Alternate-day fasting: the longest-studied intermittent fasting protocol
Evidence BADF alternates ~500 kcal 'fast' days with unrestricted 'feast' days. What Krista Varady's trial series shows on weight loss, cardiometabolic markers, and adherence — and where ADF differs meaningfully from 5:2 and 16:8.
3 min read · Last reviewed 2026-05-19
Electrolytes during fasts: what changes and what to think about
Evidence BSodium, potassium, and magnesium balance shifts during longer fasts. A look at why people feel rough on day two, what's well-established, and what's marketing.
2 min read · Last reviewed 2026-05-17
Fasting and autophagy: what the research actually demonstrates in humans
Evidence CAutophagy gets cited as the headline benefit of fasting. Most of the supporting evidence is in cells and animals — here's what's been measured in humans and the size of the gap.
2 min read · Last reviewed 2026-05-17
Fasting and women's hormones: a careful look at the evidence
Evidence CSome women report menstrual disruption with sustained fasting; some studies report no differential effect. The literature is smaller and more nuanced than confident claims on either side.
2 min read · Last reviewed 2026-05-17
The fasting mimicking diet (FMD): Longo, ProLon, and what the trials report
Evidence BA 5-day, low-calorie, low-protein diet designed to produce the metabolic signature of fasting without complete food abstinence. What the human trial evidence shows, the ProLon medical-food product, and what the longevity claims overrun.
4 min read · Last reviewed 2026-05-19
OMAD (one meal a day): the lightest evidence in the fasting space
Evidence COMAD compresses all daily eating into a single meal. The behavioural simplicity is real; the controlled trial evidence is much thinner than 16:8 or 5:2, and the safety considerations are larger.
3 min read · Last reviewed 2026-05-19
Prolonged fasts (72+ hours): safety, evidence, and when clinical supervision matters
Evidence CWhat happens biologically in fasts beyond 72 hours, the real safety considerations including refeeding syndrome, and why most of the longevity claims for multi-day fasts run far ahead of the human evidence.
3 min read · Last reviewed 2026-05-19
Refeeding after a fast: practical strategies and what the data supports
Evidence CHow to break a fast longer than 24 hours without GI distress, plus a brief note on refeeding syndrome — a rare but serious risk after prolonged fasts.
2 min read · Last reviewed 2026-05-17
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