HMB
What HMB (beta-hydroxy-beta-methylbutyrate) is, where it comes from, what EU restrictions apply and how it is taken.
This substance has no health claim authorised in the European Union. So we describe what it is and how it is taken, but do not say what it does in the body.
What it is
HMB (beta-hydroxy-beta-methylbutyrate) is a substance the body forms from the amino acid leucine; a small share of leucine becomes HMB. Supplements use the calcium salt of HMB (CaHMB), sometimes the free acid.
Calcium HMB is authorised in the EU as a novel food for sports foods and supplements, with restrictions: no more than 3 g a day, not for children or pregnant or breastfeeding women. HMB has no authorised health claims, so we do not write about muscle or recovery.
How to read the label
Capsules usually hold 500–1000 mg of calcium HMB, powders a 1–3 g serving. The label gives the salt's weight; 1 g of calcium HMB holds about 0.8 g of HMB itself. HMB is often paired with creatine, protein or vitamin D. myHMB is one maker's HMB brand.
How it is taken
Makers usually state 3 g a day, split into several doses. Do not exceed 3 g of calcium HMB a day from all products. HMB supplements are not intended for children or for pregnant or breastfeeding women.
Frequently asked questions
Is HMB an amino acid?
No, it is a product of the metabolism of the amino acid leucine. The body forms small amounts itself.
How much HMB a day is allowed?
For supplements in the EU, no more than 3 g of calcium HMB a day. Follow the dose on the pack.
Can it be combined with creatine?
Many products are made that way. Follow each substance's dose on the pack.
Other amino acids in the shop
