By RONI CARYN RABIN, The New York Times, October 8, 2009

Eating a Mediterranean-style diet — packed with fruits, vegetables, legumes, nuts, olive oil and fish — is good for your heart, many studies have found. Now scientists are suggesting the diet may be good for your mental health, too.

A study of over 10,000 Spaniards followed for almost four and half years on average found that those who reported eating a healthy Mediterranean diet at the beginning of the study were about half as likely to develop depression than those who said they did not stick to the diet.

All of the participants were free of depression when they were recruited to the study, and each filled out a 136-item food frequency questionnaire when they joined. Based on their self-reported dietary habits, they were assigned a score between 0 and 9, with the highest score reflecting the closest adherence to a Mediterranean diet.Over time, those who had scored between 5 and 9 on the Mediterranean diet were 42 percent to 51 percent less likely to develop depression, the study found, than those who scored between 0 and 2.

The study, which was funded by the Spanish government’s official medical research agency, Instituto de Salud Carlos III, does not prove a cause-and-effect relationship between the Mediterranean diet and a lower risk for depression, only an association between the two. Still, many scientists are convinced that some damaging inflammatory and metabolic processes involved in cardiovascular disease may also play a role in mental health.

The study, which was funded by the Spanish government’s official medical research agency, Instituto de Salud Carlos III, does not prove a cause-and-effect relationship between the Mediterranean diet and a lower risk for depression, only an association between the two. Still, many scientists are convinced that some damaging inflammatory and metabolic processes involved in cardiovascular disease may also play a role in mental health.

“Both cardiovascular disease and depression share common mechanisms related to endothelium function and inflammation,” said Dr. Miguel Angel Martinez-Gonzalez, professor of preventive medicine at University of Navarra in Pamplona, Spain, and senior author of the paper, published in the October issue of Archives of General Psychiatry.

“The membranes of our neurons are composed of fat, so the quality of fat that you are eating definitely has an influence on the quality of the neuron membranes, and the body’s synthesis of neurotransmitters is dependent on the vitamins you’re eating,” Dr. Martinez-Gonzalez added. “We think those with lowest adherence to the Mediterranean dietary plan have a deficiency of essential nutrients.”

The elements of the diet most closely linked to a lower risk of depression were fruits and nuts, legumes and a high ratio of monounsaturated to saturated fats, the study found.

via Vital Signs – Nutrition – Lower Depression Risk Linked to Mediterranean Diet – NYTimes.com.

The study looked at more than 14,000 high school students to determine the relationship between body mass index (BMI) and suicide attempts, as well as the relationship between believing one is overweight — whether true or not —and suicide attempts.

“Our findings show that both perceived and actual overweight increase risk for suicide attempt,” said lead study author Monica Swahn, Ph.D. That association was as strong for boys as for girls, contrary to what the researchers had originally expected.

Teens who believed they were overweight were at greater risk for suicide attempts compared to those who did not believe they were overweight. Similarly, teens with a BMI that indicated they were indeed overweight were more likely to be at risk for suicide attempts. Those who perceived themselves as overweight and who actually had BMIs that put them into the “overweight” or “obese” category also were at greater risk.

“This is a major concern since more and more children and youth are becoming overweight and obese,” said Swahn, an associate dean for research at the College of Health and Human Sciences and an associate professor in the Institute of Public Health at Georgia State University.

Hatim Omar, M.D., chief of the Division of Adolescent Medicine at the University of Kentucky, said his own experience has led him to believe that perceived obesity does increase both depression and suicide risk. “Teens are vulnerable because of their development and any actual or perceived changes in their lives, including weight issues, can potentially increase the risk of depression or suicide,” he said.

Understanding these associations can help in the development of appropriate strategies for suicide prevention, the authors said. “We cannot only focus prevention strategies on those who are overweight and who are concerned about their weight,” Swahn said, “but we also need to include youth who feel that they are overweight even though they may not be.”

“Youth feel very pressured to fit in and to fit certain limited ideals of beauty,” Swahn said.

“This study adds another wake-up call to providers, parents, teachers and society about the need for screening for depression and suicide risk in all teens, with special attention to teens with perceived or actual obesity,” Omar said.

1. Swahn M, et al. Perceived and actual overweight and risk for suicide attempts: findings from the 2007 Youth Risk Behavior Survey. Journal of Adolescent Health, 2009

Teens Who Think They’re Overweight More Likely To Try Suicide.