β-Hydroxy β-methylbutyric acid, commonly known as HMB, is a substance naturally produced in the human body during the breakdown of the amino acid leucine. It is used as a dietary supplement and as an ingredient in medical foods to support muscle health. Key points about HMB:
- It promotes muscle growth by stimulating protein production and inhibiting protein breakdown in muscle tissue.
- Supplementation with HMB can increase muscle size, strength, lean body mass, and improve exercise performance and recovery.
- HMB helps preserve or increase muscle mass and strength, especially in cases of age-related muscle loss and muscle wasting conditions such as cancer or HIV/AIDS.
- It works partly by activating the mTOR pathway, which leads to protein synthesis, and by reducing muscle protein breakdown through inhibition of specific proteolytic systems.
- HMB may also improve muscle cell membrane integrity and regenerative capacity.
- It is generally regarded as safe for use in standard doses and has not been found to cause adverse effects in long-term use in adults.
- It is found naturally in small amounts in certain foods (like grapefruit and alfalfa) but is often taken as a supplement to achieve higher doses.
HMB is popular among athletes and those looking to improve muscle mass, strength, and recovery from exercise, as well as older adults to help counteract muscle loss with aging. Despite its benefits, more research is needed for some of its potential uses. In summary, HMB is a muscle-supporting metabolite of leucine that helps build and maintain muscle through promoting protein synthesis and reducing protein breakdown.
