Supplement
HMB is a natural byproduct of leucine, an amino acid, and it appears to slow the breakdown of muscle protein in the body. People mostly look at it for muscle size and strength, and the evidence is moderate, though anaerobic capacity in 28 people and body fat in people with sarcopenia showed no clear difference. Those results are very limited, so they say little about muscle gain itself.
Sources: PMID 23286834; PMID 39071082
- Updated
- How we grade
- 17 studies cited
- Best evidence
- Grade C
- Conditions studied
- 12
- Outcomes
- 132
- Graded outcomes
- 00211
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
Muscle Size Strength
- Body Fat
- Anaerobic Capacity
- Muscle Mass: improves
Weight Loss & Maintenance
- Body Fat
- Muscle Mass: improves
- Liver Enzymes: changes; see studies
Sarcopenia
- Body Fat
- Fat-free mass (FFM): improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Body Fat No effect | NoneNo effect | 1 study | 638 people | |||
| Fat-free mass (FFM) | Improves (the measure goes up) | 273 people | ||||
General Athletic Performance
- Anaerobic Capacity
- Muscle Mass: improves
- Muscle Soreness: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Anaerobic Capacity No effect | NoneNo effect | 28 people | ||||
| Muscle Mass | Improves (the measure goes up) | 8 studies | 198 people | |||
Studies that measured muscle mass
| ||||||
| Muscle Soreness | Improves (the measure goes down) | 2 studies | 26 people | |||
Studies that measured muscle soreness | ||||||
| Power Output | Improves (the measure goes up) | 2 studies | 275 people | |||
| Body Fat | Improves (the measure goes down) | 1 study | 169 people | |||
| High-density lipoprotein (HDL) | Improves (the measure goes up) | 1 study | 36 people | |||
| Liver Enzymes | Changes; see studies | 1 study | 68 people | |||
| Muscle Damage | Changes; see studies | 1 study | 387 people | |||
| Blood glucose | Improves (the measure goes down) | 8 people | ||||
| Bone Mineral Density | Improves (the measure goes up) | 68 people | ||||
| Cortisol | Improves (the measure goes down) | 55 people | ||||
| Fatigue Symptoms | Improves (the measure goes down) | 63 people | ||||
| Food Intake | Changes; see studies | 125 people | ||||
| Growth Hormone | Improves (the measure goes up) | 29 people | ||||
| IGF-1 | Improves (the measure goes up) | 29 people | ||||
| Interleukin 6 | Improves (the measure goes down) | 29 people | ||||
| Low-density lipoprotein (LDL) | Improves (the measure goes down) | 36 people | ||||
| Oxygen Uptake | Improves (the measure goes up) | 8 people | ||||
| Testosterone | Improves (the measure goes up) | 55 people | ||||
| Total cholesterol | Improves (the measure goes down) | 36 people | ||||
| Training Volume | Improves (the measure goes up) | 63 people | ||||
| Triglycerides | Improves (the measure goes down) | 8 people | ||||
| Urea | Improves (the measure goes up) | 8 people | ||||
Body Composition
- Anaerobic Capacity
- Muscle Mass: improves
- Power Output: improves
Muscle Recovery
- C-Reactive Protein (CRP)
- Muscle Soreness: improves
- Power Output: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| C-Reactive Protein (CRP) No effect | NoneNo effect | 20 people | ||||
| Muscle Soreness | Improves (the measure goes down) | 2 studies | 40 people | |||
Studies that measured muscle soreness | ||||||
| Power Output | Improves (the measure goes up) | 2 studies | 46 people | |||
| Muscle Damage | Changes; see studies | 1 study | 370 people | |||
| Cortisol | Improves (the measure goes down) | 46 people | ||||
| Fatigue Symptoms | Improves (the measure goes down) | 26 people | ||||
| Range of Motion | Improves (the measure goes up) | 14 people | ||||
| Testosterone | Improves (the measure goes up) | 46 people | ||||
| Training Volume | Improves (the measure goes up) | 46 people | ||||
Football Performance
- Anaerobic Capacity
- Muscle Mass: improves
- Muscle Soreness: improves
Running Performance
- Anaerobic Capacity
- Muscle Mass: improves
- Power Output: improves
Volleyball Performance
- Cortisol
- Muscle Mass: improves
- Power Output: improves
Muscle Size & Strength
- Anaerobic Capacity
- Muscle Mass: improves
- Muscle Soreness: changes; see studies
Key findings
- Blood glucoseImproves (the measure goes down)
- Body Fat
- Anaerobic Capacity
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- Grade C
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Studies cited
17 studies from PubMed
- The Role of HMB Supplementation in Enhancing the Effects of Resistance Training in Older Adults: A Systematic Review and Meta-Analysis on Muscle Quality, Body Composition, and Physical Function.
- Effects of β-hydroxy-β-methylbutyrate (HMB) supplementation on lipid profile in adults: a GRADE-assessed systematic review and meta-analysis of randomized controlled trials.
- Body composition in 70-year-old adults responds to dietary beta-hydroxy-beta-methylbutyrate similarly to that of young adults
- The effect of HMB supplementation on body composition, fitness, hormonal and inflammatory mediators in elite adolescent volleyball players: a prospective randomized, double-blind, placebo-controlled study
- Beta-hydroxy-beta-methylbutyrate (HMB) supplementation does not affect changes in strength or body composition during resistance training in trained men
- Effects of nine weeks of beta-hydroxy-beta- methylbutyrate supplementation on strength and body composition in resistance trained men
- Effects of beta-hydroxy beta-methylbutyrate on power performance and indices of muscle damage and stress during high-intensity training
- Effects of calcium beta-hydroxy-beta-methylbutyrate (HMB) supplementation during resistance-training on markers of catabolism, body composition and strength
- Beta-hydroxy-beta-methylbutyrate ingestion, Part I: effects on strength and fat free mass
- The Effects of Beta-Hydroxy-Beta-Methylbutyrate Supplementation on Recovery Following Exercise-Induced Muscle Damage: A Systematic Review and Meta-Analysis.
- Effects of oral supplementation of β -hydroxy-β -methylbutyrate on muscle mass and strength in individuals over the age of 50: a meta-analysis.
- Effects of oral administration of β-hydroxy β-methylbutyrate on lean body mass in older adults: a systematic review and meta-analysis
- Supplementation with the Leucine Metabolite β-hydroxy-β-methylbutyrate (HMB) does not Improve Resistance Exercise-Induced Changes in Body Composition or Strength in Young Subjects: A Systematic Review and Meta-Analysis
- Effects of beta-hydroxy-beta-methylbutyrate supplementation on strength and body composition in trained and competitive athletes: A meta-analysis of randomized controlled trials
- Exercise-induced muscle damage is not attenuated by beta-hydroxy-beta-methylbutyrate and alpha-ketoisocaproic acid supplementation
- β-Hydroxy-β-methylbutyrate free acid reduces markers of exercise-induced muscle damage and improves recovery in resistance-trained men
- The effects of β-hydroxy-β-methylbutyrate or HMB-rich nutritional supplements on sarcopenia patients: a systematic review and meta-analysis.