Fortification of grain products with the B vitamin folate may help reduce memory loss in the over-60 set. That’s the implication from a careful look at data from a recent nationwide health and nutrition survey, NHANES III.
Researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston, Mass., were looking for a relationship between blood homocysteine levels and memory loss. Earlier, their research had established that homocysteine levels were higher in elderly people with low intakes of B vitamins, especially folate.
They had also validated reports that homocysteine–a byproduct of our own amino acid metabolism–increases risk of stroke, which is a major player in the loss of cognitive function. But they wanted to see if high homocysteine levels or low B vitamin status had a more subtle influence in memory loss among people over age 60.
That’s because B vitamins are involved in the synthesis of chemicals crucial to brain function, according to nutritional epidemiologist Martha Morris, who led the study. Or, homocysteine itself might be toxic to nerve cells. Morris collaborated with Paul Jacques, Irwin Rosenberg and Jacob Selhub at the Boston center, which is funded by the Agricultural Research Service, USDA’s chief scientific research agency.
Luckily, the NHANES III included a sensitive test of recall after a short delay, one that can identify individuals with a milder loss of recall.
Others had reported that homocysteine was related to Alzheimer’s disease, as well as to poor cognitive function in elderly both with and without dementia. Perhaps 75 percent of dementia is due to stroke or Alzheimer’s disease, which is now thought to develop from minor strokes. So the researchers excluded data from people who had suffered a stroke.
Their analysis showed elevated homocysteine levels were associated with memory loss. But the survey subjects whose blood folate levels were in the upper half appeared to be protected from memory loss even if their homocysteine levels were high.
The take-home message: Keep folate levels up. And that’s easy now; virtually all grain products have been fortified with the vitamin since 1998.