BCAAs, also known as “branch-chain amino acids” are three essential amino acids (1) leucine, (2) isoleucine, and (3) valine, each of which has unique properties.
Amino acids are the building blocks of protein; they are chemical compounds that, when linked together, form proteins. When protein is ingested, our bodies break it down into amino acids before it’s absorbed into the bloodstream and used by the body.
Of the 20 amino acids our body uses, 11 are non-essential, meaning they do not need to be directly consumed to be formed. On the other hand, there are 9 essential amino acids – 3 of which are BCAAs – that the body cannot make, and thus must be supplied by food.
The reason BCAA supplements are important is because they are the only amino acids which are not metabolized by the liver, making them directly available to muscle tissues, where they act in a number of positive ways.
Meat and whey protein contain high concentrations of BCAAs. And if you’re trying to watch your weight, one of the benefits of using supplementation versus whole foods is that the benefits of BCAAs can be realized without the consumption of extra calories. Additionally, particularly around workouts, supplementing with BCAAs versus eating whole proteins keeps blood flow in the working muscles and away from the GI tract. When you ingest intact protein, you divert blood to the gut to aid in digestion.
5 BCAA Supplement Benefits
- BCAAs enhance protein synthesis. There is a gene in muscle cells called mTOR which essentially “turns on” muscle protein synthesis. Ingestion of BCAAs, particularly leucine, activates this pathway and leads to increased muscle protein formation. This begs the question “Why take all 3 BCAAs when leucine alone stimulates protein synthesis?” Since discovery of this pathway is still relatively recent, there is not a lot of research looking at the benefits of BCAA supplementation versus leucine supplementation alone, despite a large body of research supporting the anabolic properties of BCAAs and leucine alone (just not head-to-head).
As of now, until that research is available, and given what we do know about the other benefits of BCAA supplementation, I am still recommending a mix of BCAAs, though perhaps with a higher percentage of leucine.1 It should be noted that mTOR activation has also been implicated in the proliferation of cancer cells.2 As with any supplement, the risks should be weighed against the benefits before a decision is made whether to use it.
- BCAAs support fat loss. There have been a number of studies which show BCAA intake correlates to decreased obesity rates. One large study examined over 4000 people and found that those with the highest intake of BCAAs had the lowest bodyweights.3 It is important to understand that correlation doesn’t mean causation. Still, the results are pretty convincing.
- BCAAs lessen the loss of lean body mass. BCAAs are well-known to be anti-catabolic, and this is especially important to anyone who is trying to lose body fat, as lean mass loss is a very real risk when a person is in a calorie-restricted state.
- BCAAs combat age-related decreases in muscle mass. The process by which they accomplish this task is outlined in the first entry of this list. Still, its implication in the elderly warrants repeating. Many older individuals look at supplementation in general as something “young guys and bodybuilders do.” This is the wrong way to look at things.
Supplementation, in many ways, is more important for the older population than it is for younger people. Specifically, mTOR activation by leucine is decreased in advanced ages. That, coupled with the metabolic slowdown that occurs with aging and the need to avoid excess calories which can lead to fat accumulation, makes leucine-rich BCAA supplementation a very good idea in older people.
- BCAAs may offer other beneficial effects. BCAAs might enhance brain function, contribute to a more positive mood, and help regulate blood sugar. When viewed in light of the other known benefits, BCAAs should be near the top of any supplement regimen list.
BCAA Supplement Recommendations
GNC RapidDrive BCAA 5000
Again, nothing can replace real food and I am not suggesting that BCAAs are necessary for fat loss and muscle gain. However, given how hard it is to optimize body composition, it is worthwhile to look at BCAAs as a possible part of a healthy lifestyle plan.
- Most research on BCAAs has been done of formulas containing 25% isoleucine, 25% valine and 50% leucine. Although the research is by no means definitive, it appears as though maximum mTOR stimulation occurs with leucine doses of at least 3 grams. Thus, depending on total amount of BCAA supplementation a person wants to use, a more leucine-rich formula may be a better choice if lower total dosage is desired. ↩
- Guertin DA, Sabatini DM. Defining the role of mTOR in cancer. Cancer Cell. 2007;12(1):9-22. ↩
- Qin LQ, Xun P, Bujnowski D, et al. Higher branched-chain amino acid intake is associated with a lower prevalence of being overweight or obese in middle-aged East Asian and Western adults. J Nutr. 2011;141(2):249-54. ↩