Copyright (c) 2010 Stephen Lau

Breast cancer is the most common cause of death in women. In a most recent cancer study, researchers announced that cancer costs the global economy nearly $900 billion a year—more than any other cause of death. The study also said that breast cancer is among the costliest forms of the disease, particularly in high-income countries, such as the United States. There may be many causes of breast cancer, one of which is a link to having too much estrogen (female hormone manufactured by the ovaries in women and in small amounts by the testicles in men) in the body. During menstruation, as well as in the latter part of each menstrual cycle, women often experience high estrogen levels. Increased estrogen may over stimulate cell growth in the breast as much as four times, and any excess of estrogen may increase the risk of cancer by stimulating cell growth in the breasts, ovaries and uterus in women. Cells dividing too rapidly may pose a risk of a genetic accident, resulting in alteration in the genetic structure of cells in the breast.

Accordingly, reducing estrogen may reduce a woman's risk of breast cancer. The question is: How to reduce the estrogen level in a woman's lifespan? The risk of breast cancer is significantly lower in Japan than that in the United States—about one-fourth. This discrepancy can be explained by the fact that the menstrual cycle of women in the United States is approximately 26 to 29 days, compared to the average of 32 days for women in Japan. So, the length of the menstrual cycles may hold the key to reducing cancer risk in women, because the shorter the menstrual cycles, the less production of estrogen, and the lower the cancer risk.

Late onset of menstruation may also reduce the number of menstrual cycles throughout a woman's lifespan, and thus reduces the risk of breast cancer.

The number of pregnancy during a woman's life may play a pivotal role in reducing the cancer risk by reducing the production of estrogen. By the same token, an early onset of menopause, may also lower the cancer risk.

If you cannot get yourself pregnant or increase the number of your pregnancy, you can at least lengthen your menstrual cycle through diet. Researchers have found that greater intake of soy protein may increase the menstrual cycles by an average of two and a half days. Therefore, take more soy products, such as tofu, miso, tempeh, soy milk and soy nuts. Research studies have also indicated that a vegetarian diet high in fruits and vegetables may delay the onset of puberty, that is, menarche in women. Lignins in oats, barley, whole wheat, nuts and seeds may inhibit estrogen synthesis; therefore, a diet rich in these foods may reduce the production of estrogen. Flaxseed, for example, gives you over 100 times more lignins than any other oil seeds and grains.

In addition, you can also protect yourself against breast cancer by eating dietary fiber. Excess estrogen in the body is sent to the liver where it is partially deactivated and excreted into the bile to be subsequently reabsorbed or eliminated. Therefore, extra dietary fiber shortens the time the excess estrogen may remain in the body.

Other than getting yourself pregnant, the only alternative to decrease the estrogen level is through diet.