Approximately one out of every three Americans will get cancer in their lifetime. The National Cancer Institute links one-third of all cancer cases to the use of tobacco and another third to the foods that we eat. In other words, approximately two-thirds of cancer cases can be prevented with diet and lifestyle modification.

Chinese and Japanese men and women have significantly lower rates of prostate and breast cancer than American men and women—approximately 90 percent less breast cancer in women and about 90 percent less prostate cancer in men. One of the main reasons for this is because of their high consumption of soy products. Even though the U.S. is the largest producer of soy in the world, Americans consume very little soy protein, if any. The Japanese people alone consume approximately thirty times more soy products than Americans.

What’s so great about soy? Soy contains powerful phytonutrients called isoflavones, such as genestein, which protect women from developing breast cancer and men from developing prostate cancer. Even if one has breast or prostate cancer, genestein will likely slow down the growth and the spread of cancer in the body.

I recommend that all my patients begin substituting soymilk and soy cheese for regular milk and cheese. I also encourage them to consume a soy protein drink daily. By mixing soymilk and frozen blueberries, strawberries, or other fruit in a blender, you can make a delicious and nutritious drink. This is an excellent way to start the day.

Many experts recommend around 35 to 40 grams of soy protein a day, which is the average amount of soy consumed by individuals in Taiwan. If you don’t enjoy soymilk, you can start by drinking half skim milk and half soymilk and then gradually increase the amount of soymilk. Other forms of soy include roasted soy nuts, tempeh, and tofu. One type of soy you should avoid is soybean oil because it is high in polyunsaturated fat. Also soy sauce, which is very high in sodium, should only be consumed in small amounts.

Another diet change I encourage is to decrease the consumption of saturated, polyunsaturated, and hydrogenated fats. This will also help reduce the risk of cancer. Saturated fats are found primarily in fatty cuts of meat, chicken skins, and dairy products—such as milk, cheese, butter, and ice cream. Polyunsaturated fats are found in sunflower oil, safflower oil, corn oil, soybean oil, and most salad dressings and cooking oils. Polyunsaturated fats actually cause more free radical damage to our body’s cells than saturated fats. This can eventually cause mutations in DNA resulting in cancer. Hydrogenated fats are found primarily in margarines and peanut butters.

I strongly recommend substituting extra virgin olive oil in place of polyunsaturated oils. Additionally, you can decrease your consumption of saturated fats by consuming extra lean free-range meats, skinning chicken, and choosing to bake or broil instead of frying. And eating red meat should be limited to once a week in the amount of about 4 ounces.

I also suggest that adults consume five to nine servings of fruits and vegetables a day, along with decreasing the consumption of sugar. This is important because sugar actually feeds cancer and decreases the function of the immune system.