Research

Energy balance

Intermittent energy restriction (IER) involving 2-3 fasting days per week produces greater short-term absolute weight loss and percentage of weight loss compared to continuous energy restriction (CER) when total energy deficit is matched.

If you struggle with daily calorie counting, try restricting calories to 400-600 kcal on 2-3 days a week (fasting days) and eating normally on the other days. This method may help you lose more weight in the short term (under 6 months) than eating slightly less every day, provided your total weekly calories are similar to the daily restriction approach.

ModerateSupportsMEDIUM confidence
Meta-analysis showed that IER had greater effects on absolute weight loss, the percentage of weight loss, and improving insulin sensitivity than CER. Subgroup analyses showed that short-term (2-3 months) intervention (P < 0.0001) was associated with weight loss.
Shasha He et al. · Obesity · 2020

Why this rating

Based on 11 RCTs (n=850), but rated 'low quality' due to high risk of performance bias and heterogeneity.

Source

Intermittent Versus Continuous Energy Restriction for Weight Loss and Metabolic Improvement: A Meta‐Analysis and Systematic Review

Shasha He et al. · Obesity · 2020

DOI 10.1002/oby.23023

Meta-analysis · 11 studiesCited 56×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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