June 3, 2024 – Women who most closely followed the Mediterranean diet had a 20% lower risk of early death, compared to others who made different dietary choices, according to a new study led by Harvard Medical School researchers.
When the researchers sought to understand how the diet may have affected women’s bodies to prolong their lives, they found fewer signs of problems in the women’s blood and other body fluids that are hallmarks of diabetes and heart problems.
But interestingly, the signs of healthy body functioning most linked to a long life were different than those measured by standard blood tests given during an annual physical. Variations in a woman’s standard cholesterol panel or in glucose checks that screen for diabetes were only minimally linked to early death, the researchers reported.
Instead, other biomarker measures were much more predictive, particularly signs of inflammation and the levels homocysteine and alanine, which are two types of amino acids that are small molecules called metabolites. Both are linked to heart and metabolism problems.
“For women who want to live longer, our study says watch your diet,” senior author Samia Mora, MD, a Harvard professor of medicine and cardiologist at Brigham and Women’s Hospital in Boston, said in a statement. “The good news is that following a Mediterranean dietary pattern could result in about one-quarter reduction in risk of death over more than 25 years with benefit for both cancer and cardiovascular mortality, the top causes of death in women (and men) in the U.S. and globally.”
The Mediterranean diet focuses on plant-based foods like vegetables, fruits, nuts, and whole grains, with the main source of fat coming from olive oil. The diet does include moderate amounts of fish, poultry, dairy, and eggs, and calls for rarely eating red meat, sweets, or processed foods.
For the study, researchers analyzed 25 years of health data for more than 25,000 women living in the U.S. The women provided detailed information about what they ate for nearly 3 years, and the researchers analyzed their health records afterward.
At the start of the study, all of the women were considered healthy and the average age was about 55 years old. In the following 25 years, nearly 3,900 of the women died. The top causes of death among the group were heart disease and cancer. Women who reported sticking most closely to the Mediterranean diet had a 23% reduced risk of early death due to any cause.
The researchers cautioned that their research was limited due to a lack of diversity in the people studied, who mainly were middle-aged and older, well-educated White women.