HYDROXYMETHYLBUTYRATE (HMB) Overview Information
Hydroxymethylbutyrate (HMB) is a chemical that is produced when the body breaks down leucine. Leucine is an amino acid, one of the building blocks of protein. People use HMB to make medicine.
HMB is used for increasing the benefits from weight training and exercise; and for treating diseases of the heart and blood vessels (cardiovascular disease), high cholesterol, and high blood pressure. In combination with the amino acids arginine and glutamine, HMB is also used for treating weight loss, weakness, and diarrhea in people with AIDS (AIDS-related wasting).
How does it work?
HMB might promote muscle growth. It seems to reduce the destructive breakdown of muscle in people with AIDS.
HYDROXYMETHYLBUTYRATE (HMB) Uses & Effectiveness 
Possibly Effective for:
- Increasing body weight and muscle in people with acquired immunodeficiency syndrome (AIDS). Taking HMB in combination with the amino acids arginine and glutamine seems to increase body weight and lean body mass in people with AIDS when used over eight weeks. This combination may also improve the way the immune system works in these people.
Insufficient Evidence for:
- Athletic performance. There is conflicting evidence about the usefulness of HMB for weight training. Some research suggests HMB might increase muscular strength and body composition, as well as reduce muscle damage. But other research shows no effect. There is also some evidence that HMB might be more effective in people who are just beginning to train than in well-trained athletes.
- Lowering blood pressure. Beginning research suggests that HMB can lower blood pressure.
- Lowering high cholesterol. Beginning research suggests that HMB can lower cholesterol.
- Diseases of the heart and blood vessels (cardiovascular disease).
- Other conditions.
HYDROXYMETHYLBUTYRATE (HMB) Side Effects & Safety
HMB seems to be safe for most people when used short-term. Doses of three grams per day or less for up to eight weeks seem to be safe.
Special Precautions & Warnings:
Pregnancy and breast-feeding: Not enough is known about the use of HMB during pregnancy and breast-feeding. Stay on the safe side and avoid use.HYDROXYMETHYLBUTYRATE (HMB) Dosing
The following doses have been studied in scientific research:
BY MOUTH:
- For treatment of weight loss, weakness, and diarrhea related to AIDS (AIDS-related wasting): 3 grams HMB in combination with 14 grams each of arginine and glutamine in two divided doses daily.






