THURSDAY, April 26 (HealthDay News) -- Regular consumption of berries, such as blueberries or strawberries, may help keep your brain functioning well as you age, new research suggests.
The study found that women with the highest intake of berries appeared to delay cognitive aging by up to 2.5 years. Cognition refers to brain activities such as thinking, remembering and reasoning.
"Given that we know that fruits and vegetables are good for our health in general, our findings add to the idea that we should be consuming more, especially berries, as a way to help maintain memory in older ages," said the study's lead author, Elizabeth Devore, an instructor in medicine at Brigham and Women's Hospital and Harvard Medical School, in Boston.
"Berries are a simple dietary intervention that may be helpful to the brain," Devore added.
Results of the study were published online April 26 in the Annals of Neurology.
Berries and other fruits and vegetables are rich in substances known as flavonoids. Flavonoids help protect the body's cells from damage and reduce inflammation.
"Flavonoids, which are antioxidants found in berries, apples, citrus fruits, tea, red wine and onions, have been shown to reduce the risk of chronic diseases such as heart disease, diabetes and cancers," explained nutritionist Nancy Copperman, director of public health initiatives at the North Shore-LIJ Health System in Great Neck, N.Y.
Berries contain a particular flavonoid called anthocyanidin. Devore said anthocyanidin helps give berries their rich colors, and it's found in fruits such as raspberries, blueberries, strawberries, cherries, elderberries, and red and concord grapes.
Devore explained that one of the things that's special about anthocyanidins is that they can cross the blood-brain barrier and that these flavonoids tend to locate in the areas of the brain responsible for memory and learning.
Another recent study, also from Harvard but from a different group of researchers, recently found that berries might help reduce a man's risk of Parkinson's disease.
The current study included data on food consumption from the U.S. Nurses' Health Study, which began in 1980 and collected dietary information every four years. In the period between 1995 and 2001, the researchers began measuring cognitive function in just over 16,000 female volunteers.
At the time the researchers started measuring cognitive function, all of the study participants were older than 70. Cognitive function was measured twice with a two-year interval between each assessment.
The investigators found that women who had the highest intake of blueberries (more than one serving a week) and strawberries (more than twice a week), appeared to delay cognitive aging by as much as 2.5 years. Devore said other berries may also contribute to a reduction in cognitive aging, but there wasn't enough consumption of other berries, cherries or grapes to be able to study the effects of these fruits. A serving of blueberries or strawberries is a half-cup, she noted.
Commenting on the study, Dr. Robert Graham, an internist at Lenox Hill Hospital in New York City, said: "Large epidemiological studies, such as this one, add to the basic science research that the antioxidant and anti-inflammatory properties of berries have a beneficial role in age-related cognitive decline. I would advise all my patients, at any age, to eat more berries. Berries are an easy, nutritious and delicious way preserve brain function."
Copperman, the nutritionist, said that "the current study demonstrates that women who consumed the most flavonoids, especially berries, had a slower cognitive decline over time than women with lower intakes. Increasing our intakes of fruits and vegetables is one of the best ways to live a healthy life."
While the study found an association between eating berries and maintaining mental function, it did not prove a cause-and-effect relationship.
Read more about the benefits of fruits and vegetables from the U.S. Centers for Disease Control and Prevention.