A diet rich in chocolate, wine, fruits and vegetables may help protect people from heart disease caused by air pollution, new research suggests.

The researchers found that elderly men were less likely to experience changes in heart function during heavy smog days if they ate foods loaded with flavonoids, an antioxidant found in plants.

For example, eating about 100 grams of blueberries (about three-quarters of a cup) every day might protect older men from smog-related heart disease, said lead researcher Jia Zhong, a doctoral student at the Harvard School of Public Health.

“We as individuals have no regular means to protect ourselves from air pollution,” said Zhong’s mentor, Dr. Andrea Baccarelli, an associate professor of environmental epigenetics at the Harvard School of Public Health. “Here we have a potential avenue where we can protect ourselves.”