What is hydroxymethylbutyrate and what is it used for?

Hydroxymethylbutyrate is a nutritional supplement that promotes protein synthesis, muscle growth, and maximum oxygen capacity. Let's look at its medical applications.

Written and verified by the doctor Mariel mendoza on September 25, 2021.

Last update: September 25, 2021

Hydroxymethylbutyrate is a metabolite derived from an essential amino acid, whose Use as a nutritional supplement has been linked to benefits. Among this, with better performance during exercise, increased protein synthesis and muscle growth.

This would be manifested, especially, among people who have not previously trained and in older adults. Let's see what we know about it.

What is hydroxymethylbutyrate?

Beta-hydroxy-beta-methylbutyrate or hydroxymethylbutyrate is a metabolite derived from leucine. Leucine is a branched and essential amino acid that participates in protein synthesis. Only 5% of this is used for the synthesis of hydroxymethylbutyrate.

This metabolite is involved in multiple functions. However, it is associated with promoting cholesterol synthesis and protein synthesis and inhibiting protein degradation or proteolysis.



Hydroxymethylbutyrate functions

We are going to detail the most relevant functions of this metabolite. Next, a list with them.

Maintenance of cell membranes and cholesterol synthesis

Hydroxymethylbutyrate participates in the maintenance of cell structure, function and growth. Because it is a precursor to beta-hydroxy-beta-methylglutaryl-coA, it is essential for the synthesis of cholesterol in the liver and muscle.

The endogenous synthesis of cholesterol is important for the repair of cell membranes. What makes it key to muscle growth.

In addition to this, in cases of intense and prolonged exercise or if there is greater catabolism of muscle proteins, there are higher cholesterol requirements. Therefore, it is speculated that a greater contribution of hydroxymethylbutyrate in these circumstances is necessary.

When the physical demand is extreme and repetitive exhaustion ensues, supplementation of this substance may be helpful.

Protein synthesis

Its contribution to protein synthesis lies in the fact that hydroxymethylbutyrate acts on intracellular signaling. This metabolite produces an increase in insulin-like growth factor type 1 in muscle cells.

This factor interacts with a receptor and initiates a cascade of events that lead to protein synthesis. The consequence is an increase in the size of the muscle cell.

In addition, it participates in cell proliferation itself, by increasing the MyoD marker, which also promotes the synthesis of other muscle cells and participates in reducing the inflammatory cascade that occurs during exercise. Stress episodes are other events that favor protein breakdown and that could be slowed down by hydroxymethylbutyrate.

Inhibition of protein degradation

In this case, hydroxymethylbutyrate participates through several mechanisms:

  • Decreases the number and activity of caspases: caspases are enzymes capable of breaking down proteins that are activated as part of cell maintenance in case of damage. They cause the self-destruction of cells that no longer perform functions in the body.
  • Inhibits the expression and activity of the proteasome of the ubiquitin-proteasome system: This system of muscle cell self-destruction is increased in cases such as starvation, prolonged and intense exercise, and advanced age.

Increased oxygen yield

Hydroxymethylbutyrate increases the maximum amount of oxygen which can be used during aerobic exercise. In addition to reducing body fat and LDL cholesterol, which enhances anaerobic exercise.



Strengthening the immune system

In addition to reducing the damage caused by protein degradation, hydroxymethylbutyrate increases phagocytosis, which is the process by which some cells surround and internalize external macrophage particles. It also promotes the production of nitric oxide and T lymphocytes.

On the other hand, it decreases the release of cytokines, which are pro-inflammatory factors. In such a way that it reinforces the immune defense system.

Hydroxymethylbutyrate as a nutritional supplement

For all the aforementioned, hydroxymethylbutyrate is used as a nutritional supplement, especially in athletes, prior to the start of strenuous preparation days. It has also shown benefits in untrained people starting sports.

Faced with advanced age and chronic sedentary lifestyle, its benefits are evaluated. In addition, it could be useful in situations that promote muscle breakdown, such as for cancer patients or prolonged prostration.

In nutritional supplements there are usually two forms of presentation. One is combined with calcium and the other in the free acid form. The latter tends to provide greater absorption and retention. Both are available in capsules, tablets, or powders.

The recommended dose is 2-3 grams in adults, divided into 3 doses.. These would be before breakfast, an hour before the exercise day and before going to sleep. In addition, it is recommended to start 2 weeks before the beginning of the training, maintaining the consumption for 2 to 8 weeks.

Supplementation with this compound is stipulated in no more than 2 months. It is what has shown security.

Is Hydroxymethylbutyrate Really Effective?

The consumption of hydroxymethylbutyrate is safe and useful in adults who have not trained before and in older adults. Too has shown benefits in physical readjustment after injury.

Ideally, combine it with exercise and a balanced diet to offer additional benefits. Additional supplementation with amino acids such as arginine and glutamine is recommended to enhance the effects.

It should not only be considered for high-performance athletes, with strenuous training, but also in pathological cases in which degradation is promoted. Here we can mention cancer, for example.