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Branched Chain Amino Acids Definition
Three of the nine nutritionally necessary amino acids are branched chain amino acids (BCAAs), leucine, isoleucine, and valine. These three components make up a popular health supplement that is largely used by athletes since it is thought that they aid in the synthesis of muscle tissue. However, the real usefulness of BCAA supplements has yet to be shown.
Branched Chain Amino Acids Benefits
The availability of other amino acids in the human body is totally dependent on BCAA advantages. BCAAs are thought to have a transitory effect on muscle mass because they compete with protein carrier molecules that transport a range of amino acids throughout the body.
The body becomes lacking in the aromatic amino acids phenylalanine, tryptophan, tyrosine, and histidine when transport proteins become saturated with high quantities of branched chain amino acids.
Overuse of BCAA supplements is likely to induce metabolic and neurotransmitter imbalance since aromatic amino acids are precursors of thyroxine, 5-hydroxytryptophan, and L-DOPA.
BCAA Benefits in Protein Synthesis
BCAA advantages in protein synthesis research are frequently restricted to rat studies, where greater doses of BCAAs promote protein synthesis while inhibiting protein catabolism. In humans, this job appears to be less about protein synthesis and more about protein catabolism and degradation inhibition.
The creation of complex molecules from simpler ones, such as the production of protein-based muscle tissue from single amino acids, is known as an anabolic effect. The breakdown of a complex molecule into its constituent elements is referred to as a catabolic effect.
Catabolism appears to be slowed by branched chain amino acids. This indicates that, while BCAA supplementation does not enhance the pace of muscle mass synthesis in people, a slower breakdown curve might result in larger amounts of muscle tissue under the proper conditions.
It’s important not to overlook the fact that, in the case of muscles, cell longevity may not be a good thing; the younger the cell, the better it functions.
Increased muscle growth is dependent on a wide range of nutritionally necessary and non-essential amino acids, not just a few. When one amino acid’s availability is harmed, it might disrupt the entire anabolic process. Even if one supplements a small group, the availability of a comprehensive spectrum of amino acids, enzymes, and transport proteins is still limited.
As a result, BCAAs’ beneficial effects on muscle growth are generally transitory, and other components for muscle synthesis decline or get outcompeted over time. Furthermore, muscle breakdown affects the availability of amino acids in skeletal muscle synthesis.
Amino acids are delivered to muscle locations via the bloodstream during and soon after a meal, where they contribute to muscle synthesis. This availability quickly reduces after a person stops eating; it is then up to the catabolic breakdown of older muscle cells to provide more amino acids for anabolic growth.
Because BCAAs slow down breakdown and hence reduce accessible quantities of free amino acids, it’s likely that these supplements will have a detrimental impact on muscle growth in the long term. When deciding to use BCAA supplements to build muscle growth, be sure to consume them just before a high-intensity workout and in combination with other necessary and non-essential amino acids.
As a result, competing amino acids have the same chance to bind with transport proteins, and immediate supplies in the blood plasma can be used. When this pre-training timeframe is followed, energy levels, muscle mass, and muscle injury levels appear to improve.
BCAA Benefits in the Brain
BCAA advantages in the brain are linked to competition for aromatic amino acid transport proteins and their consequences in neurotransmitter production, and are now being investigated as a treatment for manic episodes. Because branched chain amino acids contribute to the production of excitatory glutamate and inhibitory gamma-aminobutyric acid (GABA), they can assist in maintaining a positive nitrogen balance in the brain.
Higher amounts of BCAAs prevent the aromatic amino acids tryptophan, tyrosine, and phenylalanine from accessing the brain since they can pass the blood-brain barrier. Because tryptophan is a serotonin precursor and tyrosine and phenylalanine are catecholamine precursors, supplemental branched chain amino acids have a direct impact on the synthesis and release of serotonin and catecholamines including dopamine, norepinephrine, and epinephrine.
The full involvement of BCAAs in excitatory and inhibitory neurotransmitter production, as with the bulk of central nervous system physiology, is unknown. Excess BCAA resulted in low levels of serotonin in the brain, causing the animals to binge and grow obese, whereas BCAA supplement users frequently post questions on health forums wondering if their poor mood or mood swings may be linked to their use.
Branched Chain Amino Acids and Adipose Tissue
The liver does not create enough enzymes to catabolize leucine, isoleucine, or valine, unlike other nutritionally necessary amino acids. BCAA catabolism in peripheral tissue is controlled by the first enzyme, mitochondrial branched chain aminotransferase (BCAT2), which is found in the liver.
Although the physiology behind BCAA benefits is still unknown, it is thought that they signal the presence of nutrients to the body and brain, help to regulate protein synthesis and breakdown, play a role in insulin secretion, and may even contribute to the central nervous system’s food intake and energy balance control mechanisms.
Although muscle tissue is thought to be the primary location of BCAA catabolism, new research has implicated fat tissue or adipose tissue in the down-regulation of BCAA catabolism; it’s possible that adipose tissue prevents the body from using available BCAAs.
For example, research investigating BCAA levels in people with obesity, insulin resistance, and metabolic syndrome has discovered a relationship between having a lot of adipose tissue and having a lot of non-catabolized branched chain amino acids in the blood.
These circulating levels, as well as insulin resistance and appetite, decrease after gastric bypass surgery. The latter might be the result of a restoration to normal BCAA activity, in which these amino acids can operate as nutrition signalling molecules once more.
Correct Use of BCAA Supplements
It’s critical to utilise BCAA supplements correctly in order to get the most benefit with the least amount of risk. These are not the muscle-building miracles that they claim to be, but rather a nutritional supplement that is still being researched.
Furthermore, because BCAAs offer an energy source for cancer cells, they have been related to tumour development. As a result, supplementation should be carefully evaluated. Amino acid supplementation should be avoided by people who do not engage in frequent high-level physical exercise, since a healthy, diverse diet provides the body with every important nutrient.
To reduce the impact of adipose tissue on BCAA performance, fish and plant-based protein should be the primary sources of amino acids. In the regular diet, these foods supply necessary and balanced amounts of nutrients. High-fat diets combined with BCAA supplements can have significant negative health consequences.
In one study, mice fed high-fat diets with supplemental BCAAs had substantially higher death rates than those fed high-fat diets without supplementation. More significantly, none of the people who ate a high-fat, low-BCAA diet died.
When BCAA supplementation is regarded useful by an individual, it should be taken right before high-intensity exercise so that available levels are drawn straight from blood plasma and can briefly aid in the enhancement of high-energy exercise physiology.
To prevent competition and offer a complete package of components, BCAAs should be included in a combined essential and non-essential amino acid formulation. Finally, BCAA supplements should not be used as a long-term treatment since their effects have not been well investigated and may be hazardous.
Branched chain amino acid supplements should only be used for a limited period of time and as a temporary dietary supplement.
Branched Chain Amino Acids Citations
- Branched chain amino acids, aging and age-related health. Ageing Res Rev . 2020 Dec;64:101198.
- Branched chain amino acids in metabolic signalling and insulin resistance. Nat Rev Endocrinol . 2014 Dec;10(12):723-36.
- Branched chain amino acids and muscle protein synthesis in humans: myth or reality? J Int Soc Sports Nutr . 2017 Aug 22;14:30.
- Branched Chain Amino Acids: Beyond Nutrition Metabolism. Int J Mol Sci . 2018 Mar 23;19(4):954.
- Branched Chain Amino Acids. Annu Rev Physiol . 2019 Feb 10;81:139-164.