Which Individuals Should Particularly Take HMB

Leucine, a precursor of HMB, is recognized as having the greatest potential for stimulating muscle protein synthesis, which is due to the activity of the mTORc1 and p70S6K1 pathways. Due to the evident relationship between leucine and HMB, scientific studies have focused on comparing these two components. One of the best examples is a 2013 study published in the Journal of Physiology. Participants received 3.42 g of one of the two supplements being analyzed. Muscle protein synthesis increased to a similar extent in both groups (~110% leucine vs ~70% HMB), and in the HMB group, a 57% decrease in muscle protein degradation was also observed, indicating a strong anti-catabolic effect of this supplement. Interestingly, the effects of HMB were achieved despite the lack of insulin stimulation, which is a hormone known for its anti-catabolic properties. HMB limits muscle protein degradation in a manner similar to insulin, but acting independently of it, distinguishing it from leucine and other aminokwas, which achieve such effects mainly through insulinogenic properties. The exact mechanism of HMB action is not yet fully understood, but there are several theories that offer explanations. One of them assumes that HMB allows for the regulation of genes activated by the anabolic hormone IGF-1 in skeletal muscles. Elevated levels of this hormone supported the building and prevented the degradation of muscle tissue. Other theories show that HMB limits muscle protein breakdown by inhibiting the ubiquitin-proteasome pathway, which is involved in protein degradation, including muscle proteins. Regardless of how it works, HMB seems to be particularly beneficial among individuals at increased risk of muscle atrophy, where it allows for the limitation of degradation processes. Examples of groups of people who will particularly benefit from these properties are given in the following sections.

Training typically serves as a stimulus for muscle growth, yet high intensity, volume, and frequency of exercises may result in hindered regeneration, chronic increase in the catabolic hormone cortisol, and increased susceptibility to muscle atrophy. In the studies conducted by Dr. J. Wilson, participants who trained up to 6 times a week observed a greater increase in strength and muscle mass when they consumed 3 g of HMB daily.

As time passes, our bodies become less and less responsive to anabolic processes triggered by protein consumption, while catabolic processes become more prominent. In elderly individuals, uncontrolled muscle loss and decreased skeletal muscle function can lead to sarcopenia, causing more frequent falls and disturbances in insulin sensitivity.

There are instances where protein consumption in the diet needs to be limited, for example, in cases of kidney issues. However, it is important to note that an adequate level of protein is one of the most significant anabolic factors for the body, and a deficiency can lead to gradual muscle wasting. In such a scenario, taking a few grams of HMB daily does not burden the kidneys and also prevents muscle atrophy.

Among the symptoms of cancer, there is the so-called cancerous cachexia, characterized by considerable weight loss. This alteration is due not only to the loss of appetite in a patient but also to physiological changes in tissues containing protein, including skeletal muscles. Research indicates that HMB supplementation in cancer patients may prevent these symptoms and increase the body's resilience.