Very long fasts
For people who have already chosen a fast past 72 hours: signs that end it, why a clinician is the default, and a few known cases with their limits.
Some people already mean many days: past 72 hours, a week, twenty, thirty. That is a different practice from a daily window and from a 36-hour stretch. People do those stretches. A phone timer is still not a hospital.
These notes are for people who already mean many days. They are not a challenge to go longer. Longer fasts is the series for a fast past a day. Open-ended and multi-day fasts explains why this timer has no cap. The clinic history is in Therapeutic fasting in the 19th–20th centuries. Eating again after many days is about the first meals after many days, which can still be dangerous. Fundamentals is the main set of notes. A timer cannot clear you.
Educational only. Not medical advice. See our disclaimer.
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- Part 1: If you already mean many days: For people who have already chosen a fast past 72 hours. These notes are not a challenge to go longer. Signs that end it, why a clinician is the default, and a few known cases with their limits.
- Part 2: Signs on a very long stretch: On a stretch past 72 hours, a quiet day is not clearance. Dizziness, confusion, chest pain, swelling, palpitations, and not being able to stand end it, including after you eat.
- Part 3: Eating again after many days: After many days without food, the first meals can still be dangerous. A clinician who can see you should plan them. We are not giving a menu, and a hospital schedule is not something to copy at home.
Fasting Fundamentals · How to make fasting easier · Longer fasts · Using the Clock · Everyday Fasting · Questions from the community · History of Fasting · Humans, Food & Feast–Famine · What Research Suggests · Fasting, myths and science