Branched chain amino acids, or BCAAs, are some of the 20 amino acids that make up protein. They are released into your body when protein is broken down, and each one serves its own purpose. BCAAs are particularly beneficial for muscle growth. Sources include red meat and dairy products.
Foods High in BCAAs
When creating a balanced diet, the notion of having to add amino acids to the list of essential vitamins and minerals may seem daunting. Fortunately, according to a study published in the December 2018 issue of Nutrients, these amino acids are actually found in any and all foods that contain protein.
In fact, the average diet likely already provides enough BCAA sources, thanks to their presence in many staple foods that contain protein. Some of the most abundant sources include:
- Turkey breast
- Ground beef
If meat is not a product you usually consume, BCAA foods also include:
- Dairy products, such as milk, yogurt and cheese
When it comes to meat, the leaner the better, because leaner meats have a higher protein content than fattier cuts. Similarly, low-fat dairy products are much better for protein intake than their fattier counterparts and are also more beneficial for health on the whole.
While animal products usually contain all 20 of the essential amino acids and plant-based products may not include this entire group, you don't have to eat meat to benefit from amino acids. As long as you eat a variety of plant-based products, your body will receive a sufficient amount of amino acids, including branched chain amino acids.
Benefits of BCAA Sources
Protein provides energy as well as supporting your mood and cognitive function. Additionally, protein not only helps with muscle growth, but also helps build, maintain and repair tissues, cells and organs throughout your body. So it is integral to everyone, not just those who are bodybuilders or frequent exercisers.
Branched chain amino acids are particularly crucial in muscle growth because of their role in protein synthesis. However, when protein enters the body, it is broken down into 20 separate amino acids that all perform individual, beneficial roles.
The three amino acids that make up the branched chain amino acids are leucine, isoleucine and valine. Leucine and isoleucine are especially beneficial to muscle strength and growth, but other amino acids also have important health functions. For example, the amino acid tryptophan aids in improved mood and reduced symptoms of depression and anxiety by helping release serotonin, a mood-regulating hormone. Further benefits include:
- Maintenance of heart health
- Keeping the immune system strong
- Aiding the respiratory system's overall health
- Increased speed of recovery following exercise
A high-protein diet is beneficial not only for its branched chain amino acid content, but also for the many other amino acids absorbed following protein breakdown.
Branched Chain Amino Acids Explained
BCAAs are a form of essential amino acid that play a key part in the metabolism of muscle proteins, which in turn can aid with muscle development and muscle growth. As mentioned, the three BCAAs are leucine, isoleucine and valine.
- Leucine, in particular, is vital to the stimulation of the molecular signaling process that leads to the synthesizing of muscle proteins. Protein synthesis is the biological process of how amino acids become protein.
- Isoleucine works in a very similar way. It is predominantly used in the healing of muscle tissue and increasing muscle endurance, so it is popular among bodybuilders and athletes looking to increase their muscle mass. In addition, isoleucine benefits energy production and helps the body restore itself following strenuous exercise, making it ideal for people who are very active.
- Valine is slightly different from its counterparts. There are various assumptions regarding the benefits of its supplementation, including treating malnutrition following drug addiction, but more research is needed to confirm these results. Valine is usually included in multivitamins alongside many other nutrients and should not be taken alone.
Single supplementation of any amino acid can lead to an imbalance of nitrogen in the body, which can cause a reduction in the effectiveness of metabolism and force the kidneys to work harder. In children, single amino acid supplementation can stunt growth and cause difficulties as they age.
The branched chain amino acid valine should never be used as a supplement in pregnant women or during breastfeeding — this can cause damage to the baby.
Branched Chain Amino Acids: Risks
There are certain risks associated with branched chain amino acids. These ordinarily do not arise from dietary intake alone, but it is important to be aware of the potential health risks associated with too much of any single amino acid in the body.
A study published in October 2017 in the journal Oncotarget attempted to ascertain a link between BCAA circulation in the body and increased risk of cardiometabolic disease (a disease relating to the heart and certain diabetic conditions) by performing tests on a group of people between ages 21 and 110. The study found that there was a quantifiable risk associated, particularly in adults. The risk did not appear as prevalent in the older demographic.
A further study published in the journal Diabetes in July 2018 found that increased levels of BCAAs increases the likelihood of heart failure and cardiovascular disease — regardless of the weight of the subject, even though obesity was initially theorized as the cause of the link between BCAA levels and heart disease. However, it is important to note that these results are based on serum BCAA and not dietary intake, which poses less of a threat due to how the body processes food.
- Gatorade Sports Science Institute: "Branched-Chain Amino Acid Supplementation to Support Muscle Anabolism Following Exercise"
- University of Rochester: "Valine"
- HelpGuide.org: "Choosing Healthy Protein"
- NCBI: Oncotarget: "Association of Circulating Branched-Chain Amino Acids With Cardiometabolic Traits Differs Between Adults and the Oldest-Old"
- Touch Endocrinology: "The Meaning of Cardiometabolic Risk in Hypertensive Patients"
- American Diabetes Association: Diabetes: "High Serum Branched-Chain Amino Acids Level Independently Predicts Incident Heart Failure—The Hong Kong Diabetes Register"
- Khan Academy: "Protein Synthesis"
- U.S. National Library of Medicine: PubChem: "I-Isoleucine"
- Harvard Health Publishing: "How Much Protein Do You Need Every Day?"
- USDA: "DRI Calculator for Healthcare Professionals"
- NCBI: Nutrients: "Food Products as Sources of Protein and Amino Acids—The Case of Poland"