BCAAs (Branched-Chain Amino Acids) – leucine, isoleucine, and valine – are essential amino acids found in muscle tissue and must be obtained through diet or supplements. Known for supporting muscle protein synthesis, BCAAs are popular among athletes for their positive effects on muscle metabolism and potential support in weight management. Safe in recommended amounts, they are low-calorie and often aid in maintaining or reducing body mass when paired with sufficient protein intake.