Branched-Chain Amino Acids
Possible Deficiencies
Only a person deficient in protein would become deficient in BCAAs, because most foods that are sources of protein supply BCAAs. Few people in Western societies are protein deficient.
Side Effects
Side effects have not been reported with the use of BCAAs. Until more research is conducted, people with ALS should avoid taking supplemental BCAAs. In one study, supplementation with a large amount of BCAAs (60 grams) caused alterations in the blood levels of tryptophan, phenylalanine, and tyrosine.3 The changes in the blood levels of these amino acids could, in theory, cause depression in susceptible individuals. Until more is known, individuals with a history of depression should consult a doctor before supplementing with BCAAs. People with kidney or liver disease should not consume high amounts of amino acids without consulting their doctor.