Aug. 23, 2010 -- Compounds found in various berries and possibly in walnuts may slow down natural aging processes in the brain, new research indicates.
What's more, blueberries, strawberries, and acai berries may help the aging brain in a crucial but previously unrecognized way, according to a study presented at the National Meeting of the American Chemical Society in Boston.
Scientists say they have found evidence that compounds in the berries and maybe walnuts activate the brain's natural "housekeeper" mechanism that cleans up and recycles toxic proteins, which have been linked to age-related mental decline and memory loss.
"The good news is that natural compounds called polyphenols found in fruits, vegetables and nuts have an antioxidant and anti-inflammatory effect that may protect against age-associated decline," Shibu Poulose, PhD, a scientist with the U.S. Department of Agriculture-Agriculture Research Service's Human Nutrition Research Center on Aging, says in a news release.
Poulose says previous research has suggested that one factor involved in aging is a steady decline in the body's ability to protect itself against inflammation and oxidative damage, which can leave people vulnerable to degenerative brain diseases, cancer, and heart disease.
He says research he's done in the past has shown that old laboratory rats that were fed for two months on diets containing high-antioxidant strawberry, blueberry, or blackberry extract showed a reversal of age-related declines in nerve function and behavior involving learning and memory.
The Benefits of Berries
In the new study involving mouse brain tissue, Poulose says he and his colleague investigated cells called microglia, which collect waste products of the nervous system, and found that in aging they stop working properly.
When that happens, the biochemical waste builds up, and the normally protective cells become overactivated to the point that they damage healthy cells.
"Our research suggests that the polyphenolics in berries have a rescuing effect," he says in the news release. "They seem to restore the normal housekeeping function. These findings are the first to show these effects of berries."
Poulose says the study provides more reason to eat foods rich in polyphenols. These include, in addition to berries and walnuts, many other fruits and vegetables, especially those with deep red, orange, or blue colors.
Frozen berries, he says, also are good sources of polyphenols and are available all year.
This study was presented at a medical conference. The findings should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.