HMB stands for β-hydroxy β-methylbutyrate, which is naturally produced in our bodies during the metabolism of the essential amino acid leucine. Leucine is a part of the food chain – we consume  it every day in foods like soybeans, beef, alfalfa, and fish.  Some proteins have more leucine than others, however it is difficult if not impossible to consume enough protein through supplementation or a healthy diet alone to achieve the effective amount of HMB your body needs.

HMB is important for our aging muscles.  As we age, it is inevitable that we will experience muscle loss.  Supplementing with HMB can help prevent or slow the process of muscle loss to improve overall health, strength, and mobility.

HMB aids in increasing muscle protein in the body through two dual mechanisms:

Decreasing Muscle Protein Breakdown 

HMB decreases protein breakdown by disrupting proteolysis through the ubiquitin-proteasome proteolytic pathway (a major enzymatic pathway for protein breakdown in muscle). This process helps to blunt muscle damage and recover faster.

Increasing Muscle Protein Synthesis

HMB stimulates muscle protein synthesis through multiple mechanisms, including the mTOR pathway. While the initiation of myofibrillar protein synthesis is influenced by multiple factors, mTOR is a key regulatory factor that results in a direct increase in myofibrillar protein synthesis.

Myofibrillar proteins make up the contractile apparatus in muscles. HMB helps maintain this by increasing the phosphorylation of mTOR, thus activating the mTOR signaling pathway in muscle which stimulates the initiation of protein synthesis in the muscle.  And HMB also works on decreasing myofibrillar protein degradation.

While many of these effects are shared with the essential amino acid leucine, HMB is more potent than leucine in promoting strength gains, and a study has shown that conversion of leucine to HMB is necessary for this increase in protein synthesis.

Yes, HMB does improve muscle mass through its unique dual-action of increasing protein synthesis and decreasing protein breakdown.  These mechanisms blunt muscle damage allowing you to recover faster and build muscle.

Yes, HMB has had extensive clinical studies conducted to specifically evaluate the safety of HMB, and no negative side effects have been recorded in either men or women whether young or elderly.

A summary of the effects of HMB on hematology, emotional profile, and adverse effects as measured in nine clinical studies showed only positive effects on cholesterol (7 percent decrease) and blood pressure (4.4 mm of Hg decrease).

Yes, you should consume HMB daily.  The recommended dosage is three grams per day for average-size individuals. If you want to “customize” your dosage, research has shown that 38 mg/kg body weight each day is optimal.

Research indicates that HMB supplementation can benefit virtually everyone.  Athletes, aging adults, dieters, active individuals, or those recovering from illness or injury have used HMB for decades as a highly effective supplement for improving muscle health under a variety of external stressors.  In fact, the beauty of HMB is that it performs best when stressors – such as strenuous exercise or injury – are introduced to the body.

Pregnant or lactating women are advised against taking HMB because safety studies have not yet been conducted for these populations. Also, individuals with any known medical problems and adolescents should consult with their physicians prior to using HMB, as they should with all dietary supplements.

In clinical studies, HMB users have consistently improved strength, reduced muscle damage, and have also improved body composition with exercise when compared with placebo test subjects. Research suggests that HMB supplementation also provides benefits to runners, cyclists, and other endurance-training individuals.

Newer research has also shown that the combination of HMB and Vitamin D3 improved muscle function in older adults, even without exercise.