General Wellbeing

What’s all the fuss about HMB?

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HMB is created from the branch-chain amino acid, leucine, and may help to maintain muscle mass during exercise, ageing, and illness.

HMB supplements have been used in professional bodybuilding and weightlifting for decades to maintain muscle mass, but HMB might also help to prevent injuries and falls, and maintain quality of life into older age.

What is HMB exactly?

HMB stands for β-hydroxy-β-methyl butyric acid–you can see why it’s much easier to abbreviate it to “HMB”–which is a metabolite of the muscle-bulking, branched-chain amino acid leucine. They have a lot in common.

Leucine is a well-researched amino acid and taking it as a supplement has been shown to increase muscle mass, improve strength, reduce body fat, prevent soreness after exercise, and support energy levels [9]. A great workout buddy, right?

According to researchers, all of these benefits come from leucine’s effects on the body's muscles–it can slow the breakdown of muscle proteins, and boost the production of new muscle fibres. But recent studies have highlighted that it’s actually HMB–which the body naturally makes from leucine–that is responsible for these effects.

Supplemental HMB is absorbed faster than other amino acids, and metabolised directly in the mitochondria of muscle cells. This means that HMB is great fuel for muscles to burn when they’re working, recovering, or resting–and might prevent muscle loss from exercise, illness, or old age.

HMB can prevent muscle loss

Muscles require a lot of energy and they will break down their own proteins when there isn’t enough fuel.

Muscles are most at risk of breakdown:

  • During and after exercise and weightlifting
  • Lack of physical activity
  • Poor nutrition
  • Over the age of 40 – muscle mass naturally declines by 3%-5% each decade
  • During and after illness or serious health events
  • Some medications cause muscle loss

Muscle loss isn’t just an issue of losing your visible gains–it can cause weakness, loss of stamina, poor co-ordination, and a greater risk of injury.

According to the latest research, HMB can help. It is quickly absorbed and can “feed” the muscles, slowing the breakdown of existing muscle proteins, while speeding up the rate that the body creates new muscle proteins. This has a net effect of maintaining or even improving muscle mass.

HMB for sport

HMB is particularly beneficial for athletes and sports recovery. Taking HMB might support the energy that muscles need to repair themselves, boost the rate of repair, and stop further breakdown of muscle. A study from 2018 showed that HMB improved recovery from exercise-induced muscle damage and reduced the amount of muscle tissue that was degraded after the injury [4].

In a 2017 study, athletes who took HMB for 12 weeks had a significant reduction in body fat and an increase in muscle mass compared to those who didn’t take the supplement. The HMB group also performed greater strength, faster recovery from training, and experienced less soreness after exercise [3].

An early study found that taking HMB before a long race protected runners against muscle tears and reduced the breakdown of muscle that naturally occurs during endurance exercise [5]. 

But what about the rest of us?

Muscle mass protects us as we age… and so does HMB

Muscle mass naturally declines by up to 5% each decade after the age of 40, which leaves us weaker and less in control of our bodies. This age-related muscle loss is called sarcopenia and increases our risk of falls and fractures, loss of independence, and poor quality of life.

A 2014 study found that those with higher muscle mass tended to live longer than those with less muscle [1], and another study from 2013 indicated that a higher percentage of muscle could contribute to a greater quality of life [2].

Effects of sarcopenia:

  • Low physical activity
  • Slow walking speed
  • Exhaustion
  • Limited reach
  • Stiffness
  • Difficulty doing favourite activities
  • Difficulty taking care of basic needs

Muscles support the body’s movement, which is one of the major determinants of quality of life. The more we can move, the happier we are – whether it’s to go for a hike or just to jot down the shops. Losing muscle mass causes a limited range of motion or restriction in our movements and been linked to disability and many serious conditions including heart disease, depression, and type 2 diabetes [10][11].

By boosting muscle growth and slowing down protein loss, HMB might help to prevent or lessen sarcopenia. A study in 2013 found that older adults who took HMB experienced less muscle loss while on bed rest than those who took a placebo [6], and another study from 2015 found that women over 65 who took HMB for 8 weeks had greater muscle density, strength and endurance [7]. Some researchers even suggest that HMB might have a role in supporting bone health, cognition, and weight managementin older age [8].


  • HMB is created from the branch-chain amino acid, leucine, and may help to maintain muscle mass during exercise, ageing, and illness.
  • Take HMB 1 hour before, or immediately after, exercise.


[1] Srikanthan, Preethi et al. (2009) Muscle Mass Index As a Predictor of Longevity in Older Adults. The American Journal of Medicine, Volume 127, Issue 6, 547 - 553.

[2] Rizzoli R, Reginster JY, Arnal JF, et al. Quality of life in sarcopenia and frailty. Calcif Tissue Int. 2013;93(2):101–120. doi:10.1007/s00223-013-9758-y

[3] Durkalec-Michalski K, Jeszka J, Podgórski T. The Effect of a 12-Week Beta-hydroxy-beta-methylbutyrate (HMB) Supplementation on Highly-Trained Combat Sports Athletes: A Randomised, Double-Blind, Placebo-Controlled Crossover Study. Nutrients. 2017;9(7):753. Published 2017 Jul 14. doi:10.3390/nu9070753

[4]   Mohammad Hossein Rahimi, Hamed Mohammadi, Hesam Eshaghi, Gholamreza Askari & Maryam Miraghajani (2018): The Effects of Beta-Hydroxy-BetaMethylbutyrate Supplementation on Recovery Following Exercise-Induced Muscle Damage: A Systematic Review and Meta-Analysis, Journal of the American College of Nutrition, DOI: 10.1080/07315724.2018.1451789

[5] Knitter, A. E., et al. (2000) Effects of β-hydroxy-β-methylbutyrate on muscle damage after a prolonged run. J Appl Physiol (1985). 2000 Oct;89(4):1340-4.

[6] Deutz, Nicolaas & Pereira, Suzette & Hays, Nicholas & Oliver, Jeffery & Edens, Neile & Evans, Chris & Wolfe, Robert. (2013). Effect of β-hydroxy-β-methylbutyrate (HMB) on lean body mass during 10 days of bed rest in older adults. Clinical nutrition (Edinburgh, Scotland). 32. 10.1016/j.clnu.2013.02.011.

[7] Berton L, Bano G, Carraro S, et al. Effect of Oral Beta-Hydroxy-Beta-Methylbutyrate (HMB) Supplementation on Physical Performance in Healthy Old Women Over 65 Years: An Open Label Randomized Controlled Trial. PLoS One. 2015;10(11):e0141757. Published 2015 Nov 3. doi:10.1371/journal.pone.0141757

[8] Engelen MPKJ, Deutz NEP. Is β-hydroxy β-methylbutyrate an effective anabolic agent to improve outcome in older diseased populations?. Curr Opin Clin Nutr Metab Care. 2018;21(3):207–213. doi:10.1097/MCO.0000000000000459

[9] Duan, Y., et al. (2016) The role of leucine and its metabolites in protein and energy metabolism. Amino Acids, 48:1.

 [10] Wang H, Hai S, Liu Y, et al. Association between depressive symptoms and sarcopenia in older Chinese community-dwelling individuals. Clin Interv Aging. 2018;13:1605–1611. Published 2018 Sep 5. doi:10.2147/CIA.S173146

[11] Mesinovic J, Zengin A, De Courten B, Ebeling PR, Scott D. Sarcopenia and type 2 diabetes mellitus: a bidirectional relationship. Diabetes Metab Syndr Obes. 2019;12:1057–1072. Published 2019 Jul 8. doi:10.2147/DMSO.S186600

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