Intermittent Fasting Guide
Intermittent fasting (IF) is an eating pattern that cycles between periods of fasting and eating. It does not prescribe specific foods — it prescribes when to eat. The most common protocols: 16:8 (fast 16 hours, eat within an 8-hour window), 5:2 (normal eating 5 days, ~500 calories 2 days), and OMAD (one meal a day).
What the Research Shows
A 2020 meta-analysis in Obesity Reviews (27 randomized controlled trials) found IF produces weight loss of 0.8–13% of body weight over 8–24 weeks — comparable to continuous calorie restriction. It does not appear to provide metabolic advantages beyond the calorie deficit it creates.
16:8 Protocol
The most popular approach: stop eating at 8pm, break the fast at noon the next day. This naturally cuts snacking and often reduces overall calorie intake by 200–500 cal/day without counting. Most people find the first 3–5 days difficult, then hunger adapts.
Who Should Avoid It
IF is not appropriate for pregnant or breastfeeding women, people with a history of eating disorders, those with type 1 diabetes on insulin, or anyone underweight. Consult a physician before starting if you take medications that require food.