Research

Hormonal

β-hydroxy-β-methylbutyrate (HMB, 3 g/day) has conditional utility for muscle hypertrophy, showing benefits primarily during high training stress or caloric deficits, but is largely neutral in well-fed, resistance-trained individuals.

If you are dieting or doing extremely high-volume training, 3g of HMB daily might help preserve muscle. If you are eating well and training normally, HMB is likely a waste of money as it shows no benefit in this group.

ModerateConditionalMEDIUM confidence
β-hydroxy-β-methylbutyrate (HMB, 3 g·day−1) demonstrated conditional utility during high training stress or caloric deficit, but was largely neutral in well-fed, resistance-trained cohorts.
Andreea Maria Mănescu et al. · Nutrients · 2025

Why this rating

Mixed outcomes reported; benefits are context-dependent.

Source

Nutritional Supplements for Muscle Hypertrophy: Mechanisms and Morphology—Focused Evidence

Andreea Maria Mănescu et al. · Nutrients · 2025

DOI 10.3390/nu17223603

narrative_review
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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