Protein Building Block May Prevent Breast Cancer
(Washington, Reuters Health, 7/14/03)

Dr. Shumin M. Zhang of Harvard Medical School in Boston, and team, analyzed data from blood tests done on 30,000 women in 1989 and 1990. The researchers compared blood levels of cysteine, a protein building block, for 712 of the women who had been identified in 1996 as breast cancer victims with the cysteine levels of 712 cancer-free subjects. The scientists found that women with low cysteine levels were more likely to have developed breast cancer than their peers. These findings suggests that supplementation with cysteine and/or with N-actylcystein (NAC), which is known to boost the body's cysteine production, may protect against breast cancer.