This is an extremely simplistic look at a very complicated process. Remember, soy is composed of hundreds of components all interacting together. Genistein doesn’t act alone. If it’s extracted from whole soy foods and then isolated and consumed without the other soy ingredients, it can actually have detrimental effects.
Some Soys Are Better Than Others
There are dozens of different types of soy foods available, but when it comes to nutrients and health-promoting qualities, not all soy products are the same. Some soy foods are far better for you than others. Here are six great ones:
- Fresh cooked soybeans, also called edamame, are eaten after cooking, much like peas. Cook the beans in boiling water. Then, put the whole pod in your mouth. Bite down a little on the pod, and pull it out of your mouth, using your teeth to strip the beans out.
- Dry roasted soybeans can be eaten as a snack food. There are several different surprisingly delicious flavors, such as Ranch and Cajun (my personal favorite).
- Tempeh is a traditional Asian and Indonesian food that’s growing in popularity, so you can find it in most grocery stores. It’s a cultured soy cake that sometimes has other grains or spices added to it. You can cook tempeh in a number of ways: sauté it in olive oil, bake it, put it in salads or stews, make a sandwich with it, or add it to a stir-fry dish.
- Tofu is another excellent Asian product. It is made from soybean milk curd. It looks a little like cheese and has a very mild flavor. Tofu will pick up the flavor of any dish you put it in. You can use it in at least 101 different ways, so I suggest you get a good tofu cookbook and experiment.
- Miso is a fermented soybean paste that you add to water to make miso soup.
- Natto is a fermented form of soy popular in Japan. It is commonly used in sushi rolls and with rice. Natto comes in a wide variety of flavors, but it’s much more difficult to find in grocery stores in the United States.
How much soy should you consume each day to lower your risk of breast cancer? Experts say about 4–12 ounces of a quality soy product. However, if you want to eat less soy but still get the same or even better cancer-fighting effects, you can add certain spices.
Add a Little Spice to Your Life
When you cook soy, you can exponentially enhance its anticancer power by simply adding a pinch of turmeric or cumin. Both of these spices defend against and sabotage the growth of breast cancer in many clever ways.
A 1997 study from Tufts University in Boston found that when turmeric and genistein are combined, they have a synergistic effect. In other words, each one makes the other more effective. Researchers used certain highly estrogenic pesticides, endosulfan/chlordane/DDT, to start some tumors—estradiol for others—growing in a breast-cancer-cell line in the laboratory. Both genistein and curcumin (an active ingredient extracted from turmeric and cumin) prevented the growth of the tumor cells—but not completely. When they were added together, the effect was so strong, all tumor-cell growth stopped.
Many studies show that young girls who eat soy products before they go through puberty have a substantially lower risk of breast cancer later in life. One explanation for this finding is that a woman’s breast tissue is considered “immature” before she has had her first baby. Immature breast tissue is more sensitive to environmental toxins and other carcinogens. Soy has been found to help mature the breast tissue, making it more resistant to environmental toxins. According to a study published in Carcinogenesis in 2004, exposure to soy prior to puberty triggers another protective action—it "up-regulates" the Breast Cancer 1 (BRCA1) gene, a tumor-suppression gene. In other words, soy turns on a gene that suppresses tumor growth—and keeps it on.