Genistein in Soy Can Prevent Breast Cancer with a Catch
Yes, scientists say, the Genistein in soy foods can help prevents breast cancer — but only if it is consumed during puberty. According to Dr Leena Hilakivi-Clarke, professor of oncology at the Lombardi Comprehensive Cancer Center at Georgetown:
Timing seems to be vitally important in use of this bioactive food, and if we can figure out why that is so, then we may be able to help prevent breast cancer in the widest sense possible.
Obviously, the Genistein must confer some cancer-protection on cells during breast development. There is some evidence that use of genistein in puberty cut the number of so-called “terminal end buds” in the breast, and/or modified the expression of genes in those terminal end buds, but scientists are unable to explain at this point why that would lessen the incidence of later cancers.
Another theory is that Genistein activates cells known to suppress tumors, specifically BRCA1, p53, and PTEN. Those genes may continue to be more active later in life, though the exact mechanism is not yet known.