Integrative Medicine Blog

Soy as a Potential Tool for Cancer Prevention-Risk Reduction

Eric C. Sharer, MPH, RD, CSO, CDN Thursday, June 02, 2016
Istock baked tofu

As cancer is the 2nd most common leading cause of death in the United States, it is very important to embrace a healthy lifestyle to promote cancer prevention and cancer risk reduction. One food that has been found to have a strong connection to preventing certain cancers as well as helping fight cancer that someone may have is soy foods. Read below to learn more about the cancer prevention/cancer fighting potential of soy as well as to find a tasty tofu recipe!

Soy foods are any foods that come from soy beans, and include tempeh, tofu, edamame, miso, natto, soy milk, soy cheese, soy protein powder, and soy isolates in meat alternatives. It is best to consume foods as close to their natural source as possible, so it is recommended to focus on foods closer to the soy bean such as tempeh, tofu, edamame, miso, natto, and soy milk over the other soy options when possible.

Soy is a good source of nutrients that have many health benefits. Epidemiological studies have found that soy protein may reduce the risk for cancers including breast, colon, and prostate. 1, 2

Studies show that eating soy-foods early in life decreases risk of breast cancer in adults. Studies within Asia show that Asian women who consume higher amounts of isoflavone-rich soy-foods are less likely to have breast cancer as compared to those who consume little soy. Studies suggests that children and/or teens who consume as little as one serving of soy daily decrease their risk of breast cancer later in life by 25 to 50 percent. 3, 4

Isoflavones, commonly called phytoestrogens (plant estrogens) because they bind to the same receptors in cells that bind to the hormone estrogen, are plant chemicals found in soy products. They are different, however, from estrogen in some important ways. In some tissues, isoflavones exert weak estrogen-like effects, but in others, they seem to have anti-estrogenic effects. Yet, in others, they have no effect at all.

While results of some animal studies suggest that isoflavones may be contraindicated for women with breast cancer, or possibly even those who are at high risk of this disease, human studies generally show that neither soy-foods nor isoflavone supplements have estrogenic effects on breast tissue. 4, 5 The current position of the American Cancer Society is that breast cancer patients can safely consume up to three servings of soy-foods daily.6

Research in the United States and China show that for breast cancer survivors, those who consumed the most soy products were less likely to have their cancer return, compared with those who tended to avoid soy products. 1, 7

In addition to fighting and preventing cancer, soy has been found to be helpful for other conditions, including: heart disease, relieving hot flashes, and promoting bone health for postmenopausal women. 4, 5

If you are interested in eating more soy, try this easy and tasty tofu recipe below.



2. Badger TM, Ronis MJ, Simmen RC, Simmen FA. Soy protein isolate and protection against cancer.

J Am Coll Nutr. 2005;24:146S-149S

3. Messina M, Hilakivi-Clarke L. Early intake appears to be the key to the proposed protective effects of soy intake against breast cancer Nutr Cancer. 2009;61:792-8.

4. Sharer, Eric C., MPH, RD, LDN. Vegetarian/Vegan Myths. American Dietetic Association Vegetarian Nutrition Dietetic Practice Group Web site. Published 2012.

5. Messina,Virginia, MPH, RD. Isoflavones. American Dietetic Association Vegetarian Nutrition Dietetic Practice Group Web site. Published 2009. Updated 2009.

6. Rock CL, Doyle C, Demark-Wahnefried W. et al. Nutrition and physical activity guidelines for cancer survivors. CA Cancer J Clin. 2012. 23

7. Nechuta SJ, Caan BJ, Chen WY, et al. Soy food intake after diagnosis of breast cancer and survival: an in-depth analysis of combined evidence from cohort studies of US and Chinese women. Am J Clin Nutr. 2012;96:123-132.

Tasty Baked Tofu

By: Eric C. Sharer, MPH, RD, CSO, CDN Yields 3-4 servings


1 lb. Firm tofu, drained and pressed* See below

¼ cupTamari (Gluten free soy sauce)

1/8 cupVegan Worcestershire sauce, such as Annie’s Naturals or Edwards and Sons

Optional ingredients:

Your favorite vegetables, diced. Ex. Garlic, onions, bell peppers, mushrooms, grape/cherry tomatoes, fresh ginger, fresh or ground turmeric, etc.


  1. Press tofu. See below for instructions
  2. Remove tofu from towel(s). Cut tofu cut into at least 8 slabs.
  3. Mix tamari and Vegan Worcestershire sauce together in a bowl.
  4. Oil a glass baking dish such as a 9x9 or 9 ½ x 11 Pyrex pan, using a high smoke point oil such as grapeseed oil or organic canola oil.
  5. If pan is large enough, place tofu flat in the pan. If there are too many pieces of tofu, lean the slices against each other so that they are slightly tilted ( / / / / / ). Mix tamari and Vegan Worcestershire sauce again and pour over tofu. If using other vegetables put them in a separate bowl as they will not be added until right before the dish goes into the oven. Cover the pan with a lid or cutting board and let tofu marinate for 10 minutes.
  6. After 10 minutes. Flip the tofu over and let marinate for 10 minutes longer while covering the dish. Preheat oven to 400°F. Add vegetables on top of tofu.
  7. Place dish in oven. Check tofu in 10 minutes. Flip or stir tofu/vegetables if possible. Return to the oven and cook for 5-10 minutes longer.
  8. Remove tofu when vegetables are tender and tofu is hot and slightly crispy.
  9. Serve tofu with your favorite complex carbohydrate such as roasted sweet potatoes, brown rice, quinoa, wild rice, etc.
  10. The baked tofu also goes great over a large salad.
*** If you do not have time to marinate the tofu, it is ok to place it right in the oven after

the tamari, Vegan Worcestershire Sauce, and optional vegetables are added.

Pressing Tofu-

Wrap tofu in towel or several paper towels and place directly on cutting board or on a metal baking tray.Place another cutting board or metal baking tray on top of the tofu. Place a heavy object right on top of the 2nd cutting board or metal baking tray tofu (unopened half gallon of almond milk, book, or heavy skillet for 10 minutes.