HMB 2018-02-07T11:10:14+00:00

What is HMB?

HMB is short for beta-hydroxy-beta-methylbutyrate. It is a popular exercise supplement, and HMB is a metabolite of leucine. Leucine is a branched chain amino acid (BCAA) known for its effectiveness in building muscle and improving exercise performance.

But just 5% of leucine is naturally broken down into HMB in our bodies through the process of oxidation. HMB is the main metabolite of leucine which is beneficial in slowing down the breakdown of muscle protein1.

Benefits of HMB

HMB is called an anti-catabolic agent as it slows down the process of catabolism, which is when muscle proteins are broken down. Levels of the enzyme plasma creatine phosphokinase indicate when muscle proteins have been damaged. These levels are lower when taking HMB supplements2.

By reducing muscle damage during exercise, HMB helps you recover from workouts faster so you can get back to training hard. In this way, HMB also helps you build up more muscle mass and increase your muscle strength3.

Comparing Leucine vs. HMB

Being a breakdown product of leucine, you would expect leucine and HMB to have similar properties. But on a gram per gram basis, HMB is more effective than leucine at slowing down how fast muscle proteins are broken down. To be exact, HMB is 20 times more effective than leucine for its anti-catabolic properties. However HMB is not as effective as leucine at stimulating muscle protein synthesis1.

Sources of HMB

There are dietary sources of leucine and HMB. To boost your leucine levels which in turn increases how much HMB your body naturally produces, the best options are meat, eggs and fish. HMB is also present in fish as well as in grapefruits5. If you are a vegetarian or want to supplement your dietary intake, taking HMB supplements in tablet or powder form is another option.

We naturally produce 0.2-0.4g of HMB in our bodies each day. The recommended daily dosage of HMB supplements for their anti-catabolic function is 1- 3g per day1. Taking HMB in addition to creatine monohydrate is also popular as their benefits increase when taken together7. But for muscle protein synthesis, the best choice is leucine which is more effective and cheaper.

When To Take HMB?

Take HMB just before the training session to increase its availability in your blood stream. This allows your body to use the HMB to respond better during the activity.

VIDEO: Guide to HMB

Side Effects of HMB

HMB is safe when taken in the recommended dosages. However if you have any health problems it is best to check with you doctor that HMB or any other supplements are not interacting with any medications you are taking.


  1. HMB. 2018. Available from:
  2. Panton LB, Rathmacher JA, Baier S, Nissen S. Nutritional supplementation of the leucine metabolite beta-hydroxy-beta-methybutyrate (HMB) during resistance training. Nutrition. Internet. 2000. 16(9):734-739. Available from:
  3. Nissen SL, Abumrad NN. Nutritional role of the leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB). Journal of Nutritional Biochemistry. Internet. 1997. 8(6):300-311. Available from:
  4. HMB. 2018. Available from:
  5. Maxi Nutrition. HMB Side Effects Internet. 2018. Available from:
  6. HMB. 2018. Available from:
  7. HMB in combination. Internet. 2018. Available from: