Estrogen is a natural hormone essential for female breast and sexual development. It governs your menstrual cycle, controls functioning of the ovaries and uterus and stimulates the normal growth and division of breast cells. Weight, exercise, alcohol consumption and hormone replacement therapy are all factors that influence your estrogen levels. Even the food you eat can affect the levels of estrogen in your body.
Red or orange vegetables and fruits are rich sources of beta-carotene, a precursor that is used to make vitamin A in your body. Natalie Ledesma, MS, RD, CSO, at the University of California, San Francisco, advises daily consumption of beta-carotene in the form of carrots, sweet potatoes, melon, squash or mango. Beta-carotene and chemically-related carotenoid compounds are effective in reducing the growth of estrogen receptor positive and negative breast tumor cells. High levels of beta-carotene are associated with up to 50 percent reduction in the risk of breast cancer.
Soybeans and Soy Foods
Soybean and related soy products are high in phytoestrogens, plant estrogens with weak activity in humans. These weaker estrogens appear to bind to the estrogen receptor on breast and ovarian cells and block the stronger human form of estrogen from binding. Overall this leads to lower levels of estrogen in the body and a reduced cancer risk.
Broccoli and Cabbage
Daily consumption of cruciferous vegetables, particularly broccoli and cabbage, recommends Ledesma. She notes that one Swedish study of postmenopausal women demonstrated a reduction in breast cancer risk by 20 to 40 percent from adding one to two daily servings of cruciferous vegetables. Women who ate raw or lightly cooked cabbage, including sauerkraut, three or more times per week also showed a significant decrease in breast cancer risk. Cooking the cabbage for long periods of time negated those benefits.
Oats and Whole Grains
David Grotto, RD, LD, notes that the high fiber content of foods containing oats and whole grains may block harmful estrogens. In addition to decreasing estrogen, a switch to whole grains improves overall health. High-fiber foods make you feel full and satisfied for longer, reducing the likelihood that you will overeat and gain weight. In addition, Grotto states that oats increase the activity of particular immune cells known as natural killer T cells and may enhance your body's ability to eliminate tumor cells.