Research

Hormonal

An 8-week very low carbohydrate ketogenic diet (VLCKD) significantly reduces body fat mass in competitive natural bodybuilders without compromising maximal strength, despite blunting lean mass accretion and reducing anabolic hormones.

If you are a competitive bodybuilder looking to cut fat, an 8-week ketogenic diet can help you lose significant fat mass while maintaining your strength and muscle size. However, do not expect to build new muscle mass on this diet; that requires carbohydrates. Ensure you are eating enough protein (2.5g/kg) and monitoring ketones to stay in ketosis.

ModerateQualifiesMEDIUM confidence
Fat mass significantly decreased only in the KD group... whereas, lean mass significantly increased only in the WD group... Strength was increased in both study groups... There were no significant differences between study groups.
Antonio Paoli et al. · Nutrients · 2021

Why this rating

Small sample size (n=19) and short duration (8 weeks), but randomized controlled design.

Source

Effects of Two Months of Very Low Carbohydrate Ketogenic Diet on Body Composition, Muscle Strength, Muscle Area, and Blood Parameters in Competitive Natural Body Builders

Antonio Paoli et al. · Nutrients · 2021

DOI 10.3390/nu13020374

rct · n=19Cited 134×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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