Spotting a new benefit to a popular diet

A new study of more than 25,000 middle-aged American women found that following a Mediterranean diet reduces the risk of death from all causes by nearly a quarter.

Harvard researchers report that the Mediterranean diet, which was crowned the best diet for 7 years in a row (during the study), reduces inflammation in the body and improves the body's regulation of insulin and weight management, all of which protect against heart disease, dementia, stroke, and diabetes.

At the beginning of the study, which lasted for 25 years, the women filled out health questionnaires about their eating habits, health status, height and weight, to calculate their body mass index, every 6 months during the first year, and annually thereafter.

The researchers assigned scores for adherence to the diet on a scale from zero to 9, with a higher score indicating that the woman adhered to the diet more closely.

The assessment was based on intake of 9 dietary components, including high intake of vegetables (except potatoes), fruits, nuts, whole grains, fish, and monounsaturated fats.

Over a period of about 25 years, researchers counted 3,879 deaths, including 935 cases due to heart disease and 1,531 cases due to cancer.

Women with high adherence scores of 6 or higher had a 23% lower risk of death from all causes, while women with scores of 4 or 5 had a 16% lower risk.

"Most of the potential benefits of adhering to the Mediterranean diet and mortality remain unexplained, and future studies should monitor other pathways that could mediate the reduction in mortality associated with the Mediterranean diet," the researchers said.

The study was published in the journal JAMA Network Open.