Some tout soy (tofu, soy milk, soybeans) as a superfood; others say its benefits still aren't clear. Here's the latest.
- Cholesterol: Studies consistently show soy protein tends to lower bad LDL cholesterol. And a new Canadian study shows that eating soy protein caused LDL particles to convert from a small, dense type, more apt to clog arteries, into less harmful larger particles. The FDA agrees that soy may be good for your heart.
- Hot flashes: It's doubtful eating soy (or isoflavones -- plant estrogens extracted from soy) relieves hot flashes or other menopausal symptoms, according to new research.
- Cancer: Increasing your soy intake to prevent breast cancer is unnecessary, says Regina Ziegler of the National Cancer Institute. And too much soy food or supplements of soy isoflavones could actually stimulate breast cancer growth in patients, experts caution. Soy might reduce the risk of prostate cancer or thwart its progression, but a new Harvard study failed to find significant benefits to prostate cancer patients given a low-fat, high-soy diet.
- Bones: Soy may strengthen elderly spines, says new British research. But other studies show no soy benefit to young or postmenopausal bones.
- Brain: Despite recent evidence that eating tofu might increase memory loss in older people, a new University of California study finds that soy isoflavones boosted memory and cognitive function in elderly women.
The bottom line: Be moderate, not fanatical, about soy. Harvard nutritionist Walter Willett OKs a few servings a week. (Asian populations average just 1/2 cup or less of tofu daily.) But don't count on medical miracles. Check with your doctor before using soy to treat a medical problem.