When people with excess body fat eat very few carbs and more fats, they lose about 4-5% of their muscle mass within a month, and this muscle loss continues for the full 12 weeks of the diet.
See the scientific wording
Very low-carbohydrate high-fat diets cause significant decreases in total lean body mass by approximately 4-5% within 4 weeks in overfat adults, which persists throughout the 12-week intervention period.
Very strong evidence
Randomized trialsOne good-quality study supports this claim.
What the research says
1 study reviewedSupporting (1)
RCTHuman2021
The RCT design shows consistent lean mass decreases in VLCHF groups compared to control and HIIT groups. The study measured lean mass using DXA, which has high reliability for body composition assessment, and found significant decreases starting at 4 weeks that persisted throughout the intervention.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
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Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting study
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When people with excess body fat eat very few carbs and more fats, they lose about 4-5% of their muscle mass within a month, and this muscle loss continues for the full 12 weeks of the diet.
Evidence from Studies
Supporting (1)
Community contributions welcome
Contradicting (0)
Community contributions welcome
Score Breakdown
No multi-axis breakdown available yet. The overall Pro / Against score above is the best signal.
- No clinical evidence is available; the score reflects mechanistic plausibility only.