Researchers at Brigham and Women’s Hospital have investigated the reasons behind the Mediterranean diet’s association with a 23 percent reduction in overall mortality risk among American women. This long-term study, published in JAMA, followed more than 25,000 initially healthy U.S. women for up to 25 years. It found that greater adherence to the Mediterranean diet correlated with a significantly lower risk of death from all causes, including cancer and cardiovascular disease.
Key Findings
The study highlighted several biological changes linked to the diet that may explain these health benefits. Researchers detected improvements in biomarkers related to metabolism, inflammation, insulin resistance, and other health indicators.
Senior author Samia Mora, MD, director of the Center for Lipid Metabolomics at Brigham, emphasized the study’s practical implications: “For women who want to live longer, our study says watch your diet! Following a Mediterranean dietary pattern could result in about a quarter reduction in the risk of death over more than 25 years.”
Diet Details
The Mediterranean diet is predominantly plant-based, featuring:
Nuts, seeds, fruits, vegetables, whole grains, legumes as staples.
Olive oil as the primary fat source.
Moderate intake of fish, poultry, dairy, eggs, and alcohol.
Limited consumption of meats, sweets, and processed foods.
Research Insights
The study investigated the biological mechanisms behind the Mediterranean diet’s benefits by analyzing a panel of around 40 biomarkers. Significant findings included:
Major contributions from biomarkers of metabolism and inflammation.
Notable effects from triglyceride-rich lipoproteins, adiposity, and insulin resistance.
Smaller contributions from branched-chain amino acids, high-density lipoproteins, low-density lipoproteins, glycemic measures, and hypertension.
Lead author Shafqat Ahmad, PhD, stressed the public health implications: “Even modest changes in established risk factors for metabolic diseases can yield substantial long-term benefits from following a Mediterranean diet.”
Study Limitations
While the study provides valuable insights, it has limitations:
Participants were predominantly middle-aged, well-educated, non-Hispanic white female health professionals.
The study relied on self-reported measures such as food-frequency questionnaires, height, weight, and blood pressure.
Despite these limitations, the study’s large scale and long follow-up period are significant strengths.
Cultural Adaptations
The Mediterranean diet has been adapted in various countries and cultures as it gained popularity. Mora noted, “The health benefits of the Mediterranean diet are recognized by medical professionals. Public health policies should promote the healthful dietary attributes of the Mediterranean diet and should discourage unhealthy adaptations.”
In summary, this landmark study underscores the potential of the Mediterranean diet to significantly reduce mortality risk, providing a compelling case for its broader adoption and public health promotion.
