Amino acids are the basic building blocks of all the proteins in the human body. Humans need 20 different amino acids in order to make proteins. Of these amino acids, 12 are called “nonessential,” because they can be manufactured within the human body. The other 8 amino acids are known as “essential” amino acids, because they cannot be produced by the human body and, therefore, must be obtained from dietary sources.
Use of amino acid supplements is part of an alternative therapy known as orthomolecular medicine. The term, “orthomolecular,” was first used by Nobel Prize winner, Linus Pauling. The central concepts behind orthomolecular medicine are that different people have inherited variant biochemical pathways, and certain abnormal pathways make people susceptible to various diseases, including cancer. In the practice of orthomolecular medicine, specific amounts of vitamins, trace elements, amino acids, and fatty acids are used to correct these biochemical abnormalities and to treat a variety of diseases.
Scientists have begun to explore the roles of amino acids in the prevention of cancer. A recent study led by Dr. Shumin Zhang indicated that high levels of the amino acid, cysteine, may be associated with a lower risk of breast cancer. In the study, women with higher cysteine levels in their plasma had a significantly lower risk of developing breast cancer, as compared to women with lower cysteine levels in their plasma. The study also demonstrated that the connection between cysteine levels and breast cancer risk was more pronounced in leaner women and in pre-menopausal women.
Because high dosages of cysteine can cause nerve damage, a cysteine precursor (a molecule that is converted to cysteine in the body), N-acetylcysteine, may be the most effective and safest alternative. As with any supplements, be sure to first consult with your integrative healthcare professional.
Different theories exist about the possible roles of amino acids in the treatment of cancer; some alternative medicine practitioners believe that:
Limiting the dietary intake of certain amino acids, such as phenylalanine and tyrosine, may stop tumor growth
The amino acid, glutathione, may help slow the progression of cancer and may help prevent cancer patients from the negative impact of radiation therapy and some chemotherapy drugs on healthy cells
The amino acid, cysteine, may help protect cancer patients from the toxic effects of certain chemotherapy drugs
As with many other complementary and alternative therapies, there is no evidence from controlled clinical trials to support these claims.
Nevertheless, many people have benefited from various amino acid therapies. As with any alternative or complementary therapies, be sure to first consult with your integrative healthcare professional and your oncologist.