HMB (beta-hydroxy-beta-methylbutyrate) B
Almost useless for trained individuals: the evidence is contradictory
Citable fact
«HMB (beta-hydroxy-beta-methylbutyrate)» — evidence level B. Dosage: 3 g per day divided into doses. Form — the calcium salt of HMB. Studied mainly in people with no training experience or under conditions of pronounced catabolism. Source: PMID 29249685, permanent link to the source in the list below.
How it works
A metabolite of leucine that can inhibit muscle protein breakdown and moderately stimulate its synthesis. In trained people these pathways are already activated by exercise.
Dosage and intake
3 g per day divided into doses. Form — the calcium salt of HMB. Studied mainly in people with no training experience or under conditions of pronounced catabolism.
Usually 30–60 minutes before training and/or before bed; the rationale for a specific time of intake is weak.
Forms
The calcium salt and the free acid have been studied. The free acid is absorbed faster but has shown no advantages in outcomes.
What is confirmed
- 2018 meta-analysis in trained and competing athletes: no effect on strength or body composition was found
- In untrained people and during bed rest it may slow muscle loss
- In a 2020 meta-analysis in young trained people, no gain in strength or change in body composition was found
- The data set is heterogeneous: some studies were funded by manufacturers
Adverse effects and limitations
- The effect in trained athletes is not confirmed
- A waste of money: the price of a course is high relative to a zero result
- Data on long-term use are limited; no serious side effects have been described
Interactions
- There are no data on clinically significant interactions with drugs
Who must not use it
- Under 18 years: Not recommended.
- Pregnancy and lactation: Not recommended.
- absence of training experience — the only situation with possible benefit
Sources
- Effects of beta-hydroxy-beta-methylbutyrate supplementation on strength and body composition in trained and competitive athletes: A meta-analysis of randomized controlled trials · Sanchez-Martinez J, Santos-Lozano A, Garcia-Hermoso A · Journal of science and medicine in sport, 2018 · PMID 29249685
- 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 · Jakubowski JS, Nunes EA, Teixeira FJ · Nutrients, 2020 · PMID 32456217
- The Top 5 Can't-Miss Sport Supplements · Antonio J, Pereira F, Curtis J · Nutrients, 2024 · PMID 39408214
See also
Open in the app
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