For older women, supplemental soy may not yield cognitive benefits

THE QUESTION Soy has gotten a lot of buzz for benefits it may offer women as they age. Is retention of cognitive abilities — thinking skills, including memory — one of those benefits?

THIS STUDY randomly assigned 313 healthy, post-menopausal women (average age, 61) to supplement their regular diet with 25 grams of soy protein or a placebo daily, either as a powder to mix in food, as a drink or as a bar. Scores from a battery of standardized tests, which measured a broad spectrum of cognitive skills at the start of the study and again 21 / 2 years later, showed that women in both groups improved slightly overall. However, there was virtually no difference between those who did and did not consume soy. Only memory related to recognizing faces (visual rather than verbal memory) showed a difference, with the soy group scoring a little better.

WHO MAY BE AFFECTED? Post-menopausal women, who sometimes try soy to relieve hot flashes. Studies have produced mixed results on this, as they have for claims that soy helps prevent breast cancer and heart disease and helps lower cholesterol. Nonetheless, soy foods are generally considered a good option because they often replace less healthful foods and are a strong source of protein, fiber, vitamins and minerals, and are low in saturated fat.

CAVEATS The study did not assess whether soy might have cognitive benefits for men or younger women.

FIND THIS STUDY June 5 issue of Neurology (www.neurology.

LEARN MORE ABOUT forgetfulness and other memory issues with aging at (click “publications,” then enter “forgetfulness” as the keyword). Learn about soy at

— Linda Searing

The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.