Soy…A Great Tasting Miracle Food
Soy foods as tofu and soymilk have been around for a while. Yet, many Americans don’t relish them. But, once you learn the health benefits, you’re sure to rank them higher on your list.
Here’s the scoop on soy.
Soy contains isoflavones. These powerful anti-carcinogenic compounds have been shown to prevent or suppress prostate cancer. The nutritional stars in isoflavones responsible for this action are genistein, daidzein and glycetein, which are potent phytoestrogens and antioxidants that help regulate hormonal balance. Japanese men who consume an average of over twenty pounds of soy products every year, are five times less likely to die from prostate cancer as American men. Isoflavones not only suppress the growth of cancer cells but also inhibit cell proliferation
The phytoestrogens, plant sources of estrogen, found in soy can also help protect against cancer of the breast, endometrium and ovary. Research studies indicate that those Chinese women in Asia who consumed about 55 grams (about 2 ounces) of soy a day (which is what they typically consume) exhibited a 60% lower risk of breast cancer.
Ipriflavone, a type of isoflavone found in soy, has been found to inhibit bone breakdown and enhance bone growth, helping to maintain bone health.
Numerous studies, including double-blind studies, suggest that its’ ability to inhibit breakdown of existing bone is similar to estrogen, but without any classical hormonal effects such as stimulating breast or uterine tissue growth, vaginal bleeding or spotting, or breast tenderness.
A two-year study investigated ipriflavones bone building effect in 198 women. Women, not receiving osteoactive drugs, took either 200mg of ipriflavones three times daily along with 1g of calcium, or only 1g calcium and a placebo. After six months of ipriflavone-calcium supplementation, spinal bone density increased 1.4%.
Although this may sound small, it’s a clinically significant amount and predicts a lesser risk of fracture. Twenty women in the placebo group experienced a 4.9% decrease in bone density after the second year.
The good news about isoflavones doesn’t end here. This nutrient also enhances the action of calcium plus improves bone strength. It improves bone strength by increasing resistance to breaking and improving the ability of bone to withstand both dynamic and impact stress.
Helps Relieve Menopause Symptoms
Their antioxidant and phytoestrogenic properties help to reduce the incidence of hot flashes and vaginal dryness.
In a study of 104 women, 51 women were given 60 grams (about 2 ounces) of isolated soy protein daily, containing 76mg isoflavones. The remaining women took 60 grams (2 ounces) of placebo, daily for 12 weeks.
The results were staggering! The soy group was significantly superior to the placebo group in reducing the number of hot flashes: a 26% reduction by week 3; a 33% reduction by week 4; and a 45% reduction in daily hot flashes versus a 30% reduction with the placebo group by week 12.
Additionally, observational studies show that only about 15% of Japanese women report hot flashes compared to 85% in the U.S.
Soy is a rich source of protein, calcium and fiber. One of its other major nutrient contributions is omega 3- fatty acid. This nutrient team helps to protect against stroke and heart disease.
Many studies have demonstrated this effect. Perhaps the best evidence comes from a review of 38 scientific studies. This meta-analysis concealed that consumption of soy protein decreased serum concentration of total cholesterol, LDL cholesterol and triglycerides.
Trouble With Tofu?
A recent preliminary study involving 3700 Japanese-American men living in Hawaii and 500 of their wives reported that men and women who ate tofu at least twice a week during middle years were more likely to show mental decline in later life, compared to those who seldom ate tofu. The researchers were surprised by the findings given that the Japanese, where tofu is a dietary staple, has a low rate of Alzheimer’s disease.
Yet an editorial that accompanied the study noted that men who ate the most tofu were also more likely to have come from poorer immigrant families, so an inadequate childhood diet could explain the increased risk of neurological problems later in life. In addition, the study’s researchers found that a history of stroke was a more predictable indicator of cognitive function, than tofu consumption.
What should you do? Since the growing body of evidence suggests that soy helps to protect against a multiple of things, I don’t advise limiting it.
Where Can You Get Soy
Soy Milk. Tofu. Soy nuts. Soy cheese. Soy burgers. Soy shakes. And the most recent addition is edamame.
Fresh soybeans, known as edamame, have recently hit the supermarket shelves and are receiving a warm welcome in many American households. This soybean is harvested just before the seeds are fully mature. They are sold as loose pods that each holds two to three edible beans.
These soybeans are sweet and have become a popular snack in the U.S.. The ready-to-cook pods are typically sold frozen in one-pound bags and are easy to prepare. You boil them for five minutes, drain them and eat them. Just squeeze the beans out of the pod and pop them right into your mouth. You can also add them to salads or pasta.
Soy supplements are another good source of isoflavones. This is a good way to guarantee a steady intake. Look for those that have isoflavones in them so you get an adequate amount of the therapeutic constituent, isoflavones.
Soy Products Have Gained The Recognition They Deserve
The FDA has finally placed its seal of approval on soy products. Products that contain at least 6.25g or more of soy protein can place on the label: “diets low in saturated fat and cholesterol that includes 25g of soy protein a day may reduce the risk of heart disease.”
Not only does soy protect against heart disease, but as you learned above, soy supplies a healthy source of protein, eases menopausal hot flashes, strengthens bone, and reduces the risk of breast and prostate cancer, and maybe even some types of colon cancer. Although the FDA has not put their seal of approval on these added benefits, recognizing the importance of soy in helping to protect against heart disease is a big step forward.
How does soy based baby formulas measure up? Since they contain less than the required amount of soy protein per serving, labels wills not carry this claim.
Albertazzi P, et al. The effect of dietary soy supplementation on hot flushes. Obstet Gynecol 1998;91:6-11.
Aldercreutz H, et al. Role of soy protein with normal or reduce isoflavone content in reversing bone loss induced by ovarian hormone deficiency in rats. Am J Clin Nutr. 1998;68:1358S-1363S.
Anderson JW et al. Meta-analysis of the effects of soy protein intake on serum lipids. New Engl J Med 1995;333:276-82.
Brezinski A, et al. Short-term effects of phytoestrogen rich diet on postmenopausal women Menopause 1997; 4:89-94.
Carrol KK, et al. Soy consumption and cholesterol reduction: Review of animal and human studies. J Nutr 1995;125:594-95.
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