Study Finds Mediterranean Diet Can Reduce Risk of Death by 23%

Following the Mediterranean diet could lower your risk of death from any cause by 23%, according to a study published in JAMA Network Open.

A prior review of various dietary patterns found that the Mediterranean diet had the most significant and consistent positive effects on cardiometabolic and anthropometric risk factors.

This diet has been repeatedly recognized as the healthiest by the U.S. dietary guidelines and endorsed by the American Heart Association, European Society of Cardiology and Australian National Heart Foundation.

The diet includes plant-based foods and healthy fats, with extra virgin olive oil as the primary fat source, according to the Cleveland Clinic.

A meta-analysis of 29 studies, involving over 1.6 million participants from ages 4 to 32 years, found that following the Mediterranean diet more closely could lower the risk of dying from any cause by 10%.

In this study published in JAMA Network, researchers sought to investigate how adhering to the Mediterranean diet affects the risk of death from any cause and how factors like inflammation, cholesterol, blood sugar and certain amino acids play a role in this risk reduction.

Researchers focused particularly on women without any symptoms for 25 years, as research in this area is lacking.

The Women’s Health Study (WHS) included 39,876 female health professionals 45 years and older, starting between April 30, 1993, and January 24, 1996.

Participants were randomly given low-dose aspirin, vitamin E or placebos to see the effects on heart disease and cancer. The trial ended in 2004 without significant findings, but participants continued to be observed.

At the beginning of the study, women provided information on their demographics, lifestyle, medical history and medications. They also reported their weight and height, from which their body mass index (BMI) was calculated, and blood pressure was recorded.

For this investigation, 28,340 participants who provided blood samples at the start were included, excluding those without biomarker measurements or dietary information. This left a total of 25,315 women supporting study results.

To assess diet adherence, a detailed food-frequency questionnaire was used.

The Mediterranean diet score, ranging from 0 to 9, measured intake of nine key food components such as vegetables, fruits, nuts and olive oil. Higher scores indicated better adherence. Participants were divided into three groups based on their scores: low (0-3), intermediate (4-5) and high (6-9).

Information of mortality was gathered through the questionnaires and confirmed using medical records and death certificates.

Blood samples collected at the beginning of the study were also analyzed to assess traditional biomarkers such as cholesterol and new markers including certain amino acids.

The study used statistical models to compare mortality rates among the different diet adherence groups, adjusting for factors like age, smoking and physical activity.

The amount of traditional and new biomarkers were also examined to explained the link between diet adherence and reduced risk of mortality.

Among the 25,315 women, mainly White, their average age was about 55-years-old.

In their 25 years of being examined, 3,879 of them died.

Women who followed the Mediterranean diet more closely had a lower risk of death compared to those who didn’t. Those with medium adherence had a 16% lower risk, and those with high adherence had a 23% lower risk.

Even after adjusting for lifestyle factors, the risk reduction stayed significant.

The biggest factors in lowering the risk were certain small molecules, inflammation, triglycerides, body mass index and insulin resistance. Other factors, including cholesterol and blood sugar, had smaller effects.

Though the researchers explored new areas, most of the potential benefits of adherence to the Mediterranean diet and morality remains unexplained, and future studies should examine other pathways that could mediate the Mediterranean diet–associated lower mortality as well as examine cause-specific mortality.