More Berries May Mean Lower Disease Risk

< Feb. 16, 2011 > -- This is "berry" good news for fruit lovers: Blueberries, strawberries, and other red/purplish fruits and vegetables may help protect against Parkinson's disease (PD), a degenerative disease that strikes older adults.

A study that looked at more than 100,000 men and women found that those who ate berries and other foods with an antioxidant chemical called anthocyanin were less likely to develop PD.

Previous studies had found that anthocyanin and other flavonoids offered other health benefits, such as lowering the risk for high blood pressure. Flavonoids are also found in apples, citrus fruit, and chocolate, but these flavonoids did not offer the protection against PD that anthocyanin did, the researchers say.

Although flavonoids in general seemed to protect the men in the study; that was not true for the women, says Xiang Gao, M.D., at Harvard Medical School and the lead researcher. Only anthocyanins offered protection for both men and women.

Broad sample

For the study, researchers collected data on more than 49,000 men in the Health Professionals Follow-up Study and more than 80,000 women from the Nurses' Health Study.

Participants filled out detailed questionnaires about their diets. Using that information, the researchers calculated the amount of flavonoids people consumed. In addition, they also looked at the consumption of tea, berries, apples, red wine, and oranges and orange juice.

Over 22 years of follow-up, 805 people developed PD. Among men, those who consumed the most flavonoids were 40 percent less likely to develop the neurodegenerative illness compared with men who consumed the least amount of flavonoids, the researchers found.

Anthocyanins - found in berries - were associated with a lower risk of PD in both men and women.

Antioxidants' role

Anthocyanins and other antioxidants are chemicals that may protect your cells against the damaging effects of oxidation, the National Library of Medicine says. This process of oxidation occurs when your body digests food, or when you are exposed to tobacco smoke or radiation.

"A lot of the mechanisms in Parkinson's boil down to how the nerve cells handle oxidative stress," says Carlos Singer, M.D., at the University of Miami.

Flavonoids may help the nerve cells to better handle this oxidative stress, Singer says.

A Medical Mystery

Parkinson's disease is a chronic, progressive illness - and a medical puzzle. Scientists know this much: The disease develops when nerve cells in an area of the brain that controls movement begin to die. The death of these cells creates a shortage of the brain chemical dopamine. Dopamine acts as a messenger, sending out signals from the brain to the muscles. As these messages fade away, muscle movement suffers. When about 80 percent of the brain's dopamine is gone, the symptoms of Parkinson's appear.

What researchers don't understand is what causes the nerve cells to die.

Here are the facts on Parkinson's disease:

• It usually shows up after age 65, but 15 percent of those diagnosed are younger than 50.
• It is slightly more common in men than in women.
• It is usually diagnosed after other diseases have been ruled out because there is no test to confirm it.
• It has no cure at this time.
• Some people have severe symptoms, but others have only mild problems.

Always talk with your health care provider to find out more information.