Roll Call

“Calcium hydroxymethylbutyrate?”Here!HMB, Calcium HMB

Synthetic

Hasn’t appeared in a scanned product yet.

As a supplement

Talk to your doctor or pharmacist.

Roll Call does not check drug interactions or assess personal safety.

The calcium salt form of beta-hydroxy-beta-methylbutyrate, a compound the body makes in small amounts from the amino acid leucine.

Why it’s used

Taken by some athletes and older adults with the goal of supporting muscle mass and limiting muscle protein breakdown, particularly around intense training or periods of reduced activity.

What the evidence is for

reducing exercise-induced muscle protein breakdown.

What the evidence says

A number of controlled trials, summarized in a position statement from the International Society of Sports Nutrition, report reduced markers of muscle breakdown and modest strength or recovery benefits at studied doses, though results are mixed and effect sizes are often small.

Dose studied

3–3 g — typical daily dose used in HMB supplementation trials.

Context

Most trials used around 3 grams per day of calcium HMB, typically split into smaller doses; benefits appear more consistent in trained or older populations than in untrained young adults.

Rumors

  1. Reducing exercise-induced muscle protein breakdown.

    Supports — suggestivehealth and safety evidence

    Studied in: young men (untrained or resistance-active) undergoing supervised resistance training.

    Measured as a biomarker.