Research By Year

2008

Effects of beta-hydroxy-beta-methylbutyrate (HMB) on exercise performance and body composition across varying levels of age, sex, and training experience: A review

This independent, peer-reviewed paper discusses the critical details of HMB studies and the variables affecting the results of these studies.  Included is a review of the current research showing how HMB works (metabolic mechanisms). This paper concludes that collectively there is not only clinical data, but also mechanistic data supporting HMB’s effect on improving body composition and increasing muscle strength.

Beta-hydroxy-beta-methylbutyrate supplementation reduces tumor growth and tumor cell proliferation ex vivo and prevents cachexia in Walker 256 tumor-bearing rats by modifying nuclear factor-kappaB expression.

This 8-week study using a rat tumor model showed that oral HMB attenuated the cachexic weight loss caused by the tumor, resulted in decreased tumor weight, and improved glucose and glycogen metabolism.  Therefore, HMB at commonly used dosages maintained healthy tissues while helping inhibit the tumor tissue growth.

Mechanism of attenuation of muscle protein degradation induced by tumor necrosis factor-alpha and angiotensin II by beta-hydroxy-beta-methylbutyrate.

The author’s first paper detailed HMB effect on maintaining protein synthesis even after administration of lipopolysaccharide, TNF-α and angiotensin II.  This second set of experiments in cultured muscle cells showed that HMB attenuated a specific pathway involving caspase 3 and 8, PKR (RNA dependent protein kinase), and reactive oxygen species (ROS) known to activate the ubiquitin-protease pathway.  These data provide evidence as to why HMB is effective in maintaining and building muscle mass in a wide range of conditions such as AIDS, cachexia and aging.