A recent study published in the journal Neurology found that diets high in flavonoid-rich foods may lower Parkinson's disease (PD) risk in men.  Foods high in flavonoids — compounds that occur naturally in some plants — include berries, red wine, tea, and eggplant.

Certain flavonoids show the positive effects of antioxidants, molecules that limit the effects of oxidative stress, which occurs when the body is unable to get rid of waste by-products that result from chemical reactions taking place throughout the body. Antioxidants have been trendy of late, with multiple studies showing that diets rich in antioxidants could protect against a variety of diseases including Parkinson's, Alzheimer’s, some cancers, and heart disease.

The new research, from Harvard University and University of East Anglia in Great Britain, was conducted on a large scale over a 20-year period: Around 130,000 men and women participated, of whom more than 800 developed Parkinson's. Male participants who ate the most flavonoids were 40 percent less likely to develop PD than those who ate the fewest. No similar link was found in women. The gender specificity may open new avenues for future research, especially since men’s Parkinson’s risk overall is somewhat higher than women’s.

This was the first longitudinal study (an observational study conducted over the course of a long period of time, usually decades) investigating the role of flavonoids in preventing PD.

“I think that this study doesn’t represent a solid enough result to tell people to eat more flavonoids,” says Alberto Ascherio, MD, PhD, of the Harvard School of Public Health, who oversaw some of the research. “In order to really show scientific accuracy, researchers will need to do several similar such studies.”

“This is the first flavonoid study to focus specifically on PD, and the results are good,” said The Michael J. Fox Foundation’s Maurizio Facheris, MD, MSc. “However, while we can certainly encourage people to eat more berries, there is still much work to be done to understand how preventive such dietary changes may be.”