Eating leafy greens may help slow mental decline.
Researchers studied 960 men and women ages 58 to 99 who completed food frequency questionnaires and had two or more cognitive assessments over an average of almost five years of follow-up.
Among many other foods, the researchers recorded the number of servings of lettuce, spinach, kale and collard greens. At least twice over the course of the study they administered cognitive tests covering memory, spatial ability and perceptual speed.
Those who ate the most leafy vegetables — one to two servings a day — scored the equivalent of 11 years younger on tests of mental ability than those who ate little or none. Greens contain lutein, folate, beta carotene and other nutrients known to affect aging.
Could the same effect be obtained with supplements containing these nutrients? Probably not. “The evidence for supplements is not positive, either from observational studies or clinical trials,” said the lead author, Martha Clare Morris, a professor of epidemiology at Rush University in Chicago. “The nutrients in food have many different forms and interactions. A specific formulation put in a pill with the same effect? That’s wishful thinking.”