|
Leafy
Green Vegetables Keep
Brain Sharp Through Aging
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. "The men took a
series of cognitive tests at the beginning of the study period
and then repeated those tests three years later," explained Tucker.
"We compared their first and second scores, reviewed their responses
to dietary questionnaires, and took blood samples in order to
see if nutrient levels in the diet and the blood were related
to changes in cognitive performance."
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.
"Unlike our prior work with this population, in which we observed
an association between low folate levels and lower cognitive test
scores at one point in time, this study looks at the effects of
these nutrients over time." Tucker says, "That is an important
step in establishing causality."
Reference
Source 125
September
21, 2005
For
more information on how to prevent other diseases, use
PreventDisease.com's "Quick
Prevention Resources".
|