Fasting protocols
Which protocol you are following changes the answer to almost every other question on this site, including what breaks your fast.
16:8 intermittent fasting
16 hours daily · beginnerSixteen hours fasting, an eight-hour eating window, every day. The most common entry point and the one most people mean by "intermittent fasting".
OMAD (one meal a day)
23 hours daily · advancedA single meal in roughly a one-hour window, fasting the other 23. Simple to describe, harder to meet nutritional needs on.
24-hour fast
24 hours · intermediateDinner to dinner, once or twice a week. Long enough to deplete liver glycogen and shift toward fat oxidation.
48-hour fast
48 hours · advancedTwo full days. Electrolytes start to matter here rather than being optional.
72-hour fast
72 hours · advancedThree days, usually undertaken for autophagy rather than weight loss. Not a beginner protocol and not appropriate for everyone.
Water fasting
Variable · advancedWater only, no calories from any source, for an extended period. The strictest common protocol and the one with the most medical caveats.
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