Research

Hormonal

Ketogenic diets are effective for fat mass reduction but are less effective than carbohydrate-rich diets for muscle mass gain, potentially due to reduced testosterone and IGF-1 levels.

If your main goal is to build muscle, avoid ketogenic diets as they may hinder growth. If your goal is fat loss, keto works, but monitor your strength training performance.

ModerateQualifiesMEDIUM confidence
In the context of hypertrophy and muscle mass gain, KD has limitations, making it less advantageous during muscle-building phases... Bodybuilders following KD have been observed to experience a decrease in testosterone and IGF-1 levels... it is less effective than carbohydrate-rich diets when the goal is to increase muscle mass.
Volha Babrova et al. · Journal of Education Health and Sport · 2025

Why this rating

Based on specific studies on bodybuilders and trained men.

Source

A Review of Strategies for Achieving Simultaneous Muscle Mass Gain, Maintenance, or Minimal Loss During Fat Reduction: Insights from the Last 5 Years

Volha Babrova et al. · Journal of Education Health and Sport · 2025

DOI 10.12775/jehs.2025.79.59391

narrative_reviewCited 2×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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