Can Amino Acids Increase Fat Loss? What the Evidence Says
Sports nutrition experts generally accept that increased consumption of protein through the diet and supplemental protein, especially with BCAAs, can increase exercise performance and support muscle growth under special circumstances, and it can prevent some forms of sarcopenia.
While there is plenty of research on the role of general high-protein diets on fat loss and body composition in general, researchers, nutritionists, and athletes alike are interested in the role that specific amino acids might have in fat oxidation, commonly known as “fat burning."
Here is the summary of the research:
- An increased complete protein intake through high-protein diets is associated with greater fat loss.
- BCAA supplementation (76% leucine), together with moderate calorie restriction has demonstrated significant losses of abdominal visceral fat, which is the type of fat that covers organs, high proportions of which are associated with type 2 diabetes and heart disease.
- Taking BCAAs to support weight loss in people with type 2 diabetes is controversial. In some studies, it was shown to improve glucose control, while in others, BCAA supplementation in obese people with type 2 diabetes showed a potential to increase insulin resistance. This is because, in general, body compositions higher in fat correlate with high levels of BCAAs, and recent studies suggest that BCAA may interfere with the oxidation of fatty acids, leading to insulin resistance.
- Circulating BCAAs in the blood are generally associated with a greater percentage of body fat in non-athletes.
- BCAA supplementation in resistance-trained athletes on a hypocaloric diet can maintain muscle mass and performance while losing fat mass.
Research shows that while a high-protein diet together with exercise is associated with fat loss, an increased intake of specific amino acids, namely BCAAs, for achieving fat loss is only effective in specific cases. More specifically, BCAA supplementation may boost fat loss while preserving muscle mass and supporting performance in trained athletes, but it isn’t effective for healthy non-athletes who want to lose weight or for treating obesity.
If you or a client think that they would benefit from increased protein or specific amino acid intake, you can work with them to see how to maximize protein intake through diet. If it is more cost-effective for them to take a supplement, if they are still having trouble meeting protein intake through diet alone, or if they want to supplement with specific BCAAs to take advantage of the benefits for athletes, they may consider supplementation. Make sure you talk to your client about what they should consider before deciding to take a supplement.
Protein intake is an essential part of a healthy lifestyle for athletes and non-athletes alike. Athletes who have specific performance or body composition goals may find benefits to increasing their intake of specific amino acids, specifically BCAAs.
It is generally accepted that increased BCAA intake through diet or through supplementation can help to improve muscle mass, performance, energy metabolism, and overall body composition in people who engage in regular moderate to vigorous exercise. However, there is no substantial support for BCAA supplementation use on its own as a weight-loss aid.