Memory Loss? Eat Some Blueberries

September 13, 1999

A diet rich in blueberry extract reversed some loss of balance and coordination and improved short-term memory in aging rats, USDA reports. If the findings translate to human behavior, too, a lot more blueberries will be sold.

"If this finding holds for humans, it should further encourage consumption of fruits and vegetables high in antioxidants to help fight the effects of aging," says Agriculture Secretary Dan Glickman. The findings will be published in the Sept. 15 issue of the Journal of Neuroscience.

Researchers fed extracts of blueberry, strawberry or spinach daily for eight weeks to 19-month old rats with an age equivalent to 65 or 70 year old humans. All three extracts improved short-term memory; only the blueberry extract improved balance and coordination.

This is the first study that shows fruits and vegetables actually reversing dysfunctions in behavior and nerve cells. Earlier, the same researchers, led by neuroscientist James A. Joseph of the USDA Human Nutrition Research Center on aging at Tufts University, Boston, reported that high antioxidant fruits and vegetables prevented some loss of function in aging rats.

Blueberries, strawberries and spinach test high in the ability to subdue oxygen free radicals. These oxygen radicals, that can damage cell membranes, DNA and other delicate internal machinery, are blamed for many of the dysfunctions and diseases associated with aging.

"Motor behavior is one of the first things to go as you age," says Joseph. "The improvements we saw in coordination and balance are really significant. In other studies, little else has reversed these deficits in motor function."

A decline in motor skills starts at about 12 months for rats. By 19 months, the length of time rats can walk a narrow rod before losing balance normally declines from 13 to 5 seconds. After eating blueberry extract, the rats stayed on the rod for 11 seconds on average.

Joseph and psychologist Barbara Shukitt-Hale were the lead researchers on the project. They may be contacted on the Internet at joseph_ne@hnrc.tufts.edu or hale_ne@hnrc.tufts.edu.