How to Calculate Intermittent Fasting
What is Intermittent Fasting?
Intermittent fasting (IF) cycles between periods of eating and fasting. The most common protocols are 16:8 (fast 16 hours, eat within 8-hour window), 18:6, and 5:2 (two 500-600 kcal "fast days" per week). Benefits include improved insulin sensitivity, metabolic flexibility, and appetite regulation.
Step-by-Step Guide
- 116:8: stop eating at 8pm → break fast at noon the next day
- 2Time-restricted eating aligns feeding with circadian biology
- 3Autophagy (cellular cleanup) accelerates after 16–24 hours of fasting
- 4Fasting insulin drops significantly after 12–14 hours without food
Worked Examples
Input
Last meal 8pm · 16:8 protocol
Result
Break fast at 12:00 next day · Eating window 12:00–20:00
Coffee/tea/water allowed during fasting window
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