| The Chinese say that breast cancer is a rich woman's | | | | timing exposure to genistein, an estrogen, before |
| disease and indeed there is a very small incidence of | | | | puberty causes mammary gland differentiation. Once |
| it in China and Japan. Families in both countries eat a | | | | a dell has become differentiated it is less prolific and |
| diet rich in soybeans and tofu. The health benefits of | | | | less likely to develop cancer. However, if the |
| soy are in isoflavones which are a class of plant | | | | estrogen is administered to an animal after the |
| estrogen found in a high concentration in soy. In | | | | development of an estrogen-responsive tumor, the |
| particular genistein occurs in soy products such as | | | | growth of this tumor will be stimulated. |
| tofu, soy protein isolates, soy flour and some | | | | This also has serious repercussions many women in |
| estrogen dietary supplements. | | | | their early to mid fifties are ingesting genistein and |
| The reason that genistein has come under medical | | | | other isoflavones in supplements daily. They are |
| scrutiny is the fact that it activates estrogen | | | | marketed as a safe and natural alternative to the big |
| receptors in cells, including some types of breast | | | | bad HRT products, they are deemed so safe that |
| tumor cells. Unfortunately clinical trials have been | | | | they are more often than not sold without a doctor's |
| ambiguous, and in some cases extremely | | | | knowledge or prescription and yet women over fifty |
| contradictory. Some concluded that female rats fed | | | | have an increased risk of developing breast cancer. |
| on genistein prior to puberty reduced the number of | | | | Helferich concluded that purified genistein is not as |
| chemically induced mammary tumors. Other studies | | | | potent as HRT, it can be just as dangerous because |
| showed that estradiol, the primary human estrogen, | | | | it is often taken in higher quantities. To compound |
| encouraged the growth of existing | | | | matters the components are not strictly regulated |
| estrogen-dependent breast tumors. | | | | and can differ between batches. Genistein is only one |
| University of Illinois food science and human nutrition | | | | component of the complete bean, whole soy beans |
| professor William Helferich, demonstrated that similar | | | | have a wide variety of ingredients that are biologically |
| to estradiol dietary genistein stimulates the growth of | | | | active and they may have a cumulative effect which |
| estrogen responsive tumors and dietary genistein | | | | means that eating the whole can have a different |
| interfered with treatments, such as tamoxifen, that | | | | effect from eating a small supplemental part. |
| target estrogen receptors in breast tumors. As over | | | | All of this means that the sum of the nutrients in the |
| two thirds of women with breast cancer have | | | | whole bean is greater than that of the original parts |
| estrogen-responsive tumors, this has serious | | | | combined; it is far cheaper to add whole soy beans |
| repercussions. | | | | to casseroles stews and soups than take expensive |
| Helferich concluded that the difference was the | | | | nutrient supplements. |