The Mediterranean-style diet, recommended by doctors to improve heart health, might also reduce the development of depression, according to a study published in Archives of General Psychiatry, reports HealthDay News.

Mediterranean diets consist mostly of fruits, vegetables, whole grains, beans, dairy, olive oil, red wine and fish.

“We are speaking of a relative reduction in [depression] risk of 42 percent to 51 percent,” said study coauthor Miguel A. Martinez-Gonzalez, MD, PhD, chair of preventive medicine at the University of Navarra in Spain. “This is a strong association.”

Researchers examined the Mediterranean diet adherence questionnaires of 10,000 depression-free adults by looking at nine components.

After a 4.4-year follow-up, depression was 30 percent lower in those who adhered to the diet. In addition, researchers noted that specific elements of the diet lowered depression rates.

A possible reason for this, investigators said, is that the Mediterranean diet improves the performance of the endothelium—the lining of blood vessels—which is involved in making brain-derived neurotrophic factor, or BDNF, a molecule responsible for the growth and function of nerve cells.

“Dysfunction of BDNF is thought to be responsible for some depression cases,” said Martinez-Gonzalez.

But he recommended the Mediterranean diet as a way to prevent depression—not treat it.

Another health care expert, David Mischoulon, MD, PhD, an associate professor of psychiatry at Harvard Medical School, agreed.

“If you have a family history of depression and you are concerned about it, a diet like this would probably be a good place to start,” Mischoulon said.

Learn more about the benefits of a Mediterranean-style diet here.