TargetedMuscle, boneVegan form available

HMB

A leucine metabolite; slows muscle breakdown in bed rest, old age or calorie deficit. For young trainees creatine is better.

3/5· Multiple human trialsEstimated monthly cost: ≈ 18 €

Dose

3 g daily as 3×1 g.

Timing

With meals.

⚠ Cautions

Well tolerated.

What it is

β-hydroxy-β-methylbutyrate; activates mTOR, inhibits the proteasome.

What the evidence shows

Deutz 2013 (n=24 older adults, 10 days bed rest): 3 g HMB preserved lean mass (control –2 kg). Meta-analysis in older adults: +0.35 kg muscle. Contradictory in young trainees.

Goals

Muscle, strength

Sources

Deutz NEP et al. Effect of β-hydroxy-β-methylbutyrate on lean body mass during 10 days of bed rest in older adults – RCT. Clin Nutr (2013) ↗

Last reviewed: 6 September 2026

This site is educational and does not replace medical advice. Start any supplement or drug only after consulting a doctor or pharmacist.