Leafy green vegetables could help keeping brains sharp in adults

27/09/05 According to a recent report in the American Journal of Clinical Nutrition, folate, a B vitamin found in foods like leafy green vegetables and citrus fruit, may protect against cognitive decline in older adults. The research was conducted by scientists at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University.

A team led by Katherine L. Tucker, PhD, director and professor of the Nutritional Epidemiology Program at the Friedman School of Nutrition Science and Policy at Tufts, studied a group of Boston-area men who were members of the ongoing Normative Aging Study (NAS). Tucker and her colleagues found that men who obtained more folate in their diets showed significantly less of a decline in verbal fluency skills over the course of three years than did men with lower dietary folate intake.

High folate levels, both in the diet and in the blood, also appeared to be protective against declines in another category of cognitive skills known as spatial copying. To test this, the 50- to 85-year-old study participants were asked to copy various shapes and figures, and their drawings were assessed for accuracy.

In an earlier study with the same NAS group, which corroborated the findings of other investigators, the Tufts research team observed that high homocysteine--a known blood marker of cardiovascular disease risk--was associated with lower cognitive test scores.

Since folate supplementation can help reduce blood levels of homocysteine, it was thought that this might explain folate's beneficial effects. However, in the current study, the effects of folate were independent of its impact on homocysteine, which turned out to be more strongly associated with tests of memory.