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The Mediterranean diet has not only been popular amongst peoples living in Italy, Spain and Greece and more recently in the US, but has received increasing attention from health and nutrition experts for its numerous health benefits, underscored by its ranking as the #1 overall diet by U.S. News and World Report in 2023. Its popularity is not just based on its nutritional benefits. Its simplicity, balance, and flexibility makes it an ideal choice for those seeking a delicious, sustainable and effective eating plan.

“…richness in plant-based foods, including whole grains, fruits, vegetables, beans, legumes, nuts, seeds, herbs, spices, and healthy fats like extra virgin olive oil.”

The attention the Mediterranean diet has received in the health and nutrition communities traces its roots to the 1950s, following Ancel Keys’ Seven Countries Study, which revealed lower rates of cardiovascular disease and increased longevity among populations living around the Mediterranean Sea, in particular on the Greek island of Crete. Even though Key’s original study has been criticized for its methodological flaws, this correlation was attributed to the diet’s lack of red meat and richness in plant-based foods, including whole grains, fruits, vegetables, beans, legumes, nuts, seeds, herbs, spices, and healthy fats like extra virgin olive oil. While the diets in people living in countries like Italy, Spain, Greece and Southern France have deviated significantly from the original concept with increased portion sizes, processed meat, and sugary foods, the traditional Mediterranean diet concept recommended in the US today contains moderate amounts of lean proteins such as fish, seafood, and poultry, red meats and sweets are discouraged.

Based on numerous studies since Key’s original publication, the diet’s health benefits extend beyond heart health. A study led by Zhilei Shan and colleagues from the Department of Nutrition at the Harvard T.H. Chan School of Public Health, and published in JAMA Internal Medicine in 2023, demonstrated that individuals adhering closely to a Mediterranean diet had a nearly 20% lower risk of premature death over a period of 36 years. This research, encompassing a significant sample size of over 119,000 participants from the Nurses’ Health Study and the Health Professionals Follow-up Study, utilized dietary metrics like the Alternate Mediterranean Diet score to explore the impact of healthy eating patterns. The findings demonstrate a strong association between a Mediterranean diet and reduced mortality risk, offering valuable insights for public health nutrition. While the study’s observational nature limits its ability to establish causality, the large and diverse sample size substantially strengthens the validity of its positive implications for diet and longevity. These findings have major clinical implications given the epidemic of chronic diseases like cardiovascular disease, colon and breast cancer, type 2 diabetes, neurodegenerative diseases, and respiratory diseases, which are the leading causes of death worldwide.

“The Mediterranean diet has also been linked to better brain health.”

A 2022 study led by Bayan Moustafa, DO, and colleagues, associated with various institutions including the University of Illinois at Chicago College of Medicine, and published in JAMA Network Open, revealed that high adherence to a Mediterranean diet among more than 6,300 middle-aged or older Hispanic adults led to improved overall cognition and decreased learning and memory reduction levels over seven years. This research utilized data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) and the Study of Latinos–Investigation of Neurocognitive Aging (SOL–INCA), employing the Mediterranean Diet Score (MDS) to categorize diet adherence and employing cognitive tests such as the Brief Spanish-English Verbal Learning Test and the Digit Symbol Substitution Test. The findings suggest that a culturally tailored Mediterranean diet may reduce the risk of cognitive decline and Alzheimer’s disease among Hispanic or Latino populations. While the study’s cohort design limits its ability to establish direct causality, the substantial sample size and the longitudinal follow-up enhance the robustness of its conclusions regarding diet and cognitive health. Nutrients found in the diet, such as polyphenols, antioxidants, dietary fiber and omega-3 fatty acids, are believed to have protective effects on brain cells. However, a recent randomized controlled study by a team of investigators from Rush University and published in the New England Journal of Medicine aimed to evaluate the beneficial effect of the MIND diet, a diet based on the general concepts of the Mediterranean diet failed to show a significant cognitive benefit. Among cognitively unimpaired participants with a family history of dementia, changes in cognition and brain MRI outcomes from baseline to year 3 did not differ significantly between those who followed the MIND diet and those who followed the control diet with mild caloric restriction. These negative findings of this controlled clinical trial emphasize the caution which is necessary to interpret the results from epidemiological studies.

“While not a weight-loss diet, the Mediterranean diet has been found to aid in weight management.”

A 2022 study led by Dimitrios Poulimeneas and colleagues, from the Department of Nutrition and Dietetics at Harokopio University in Athens, Greece, and published in Nutrition Research, investigated the association between adherence to a Mediterranean lifestyle and weight loss maintenance. This study was part of the MedWeight study, analyzed 470 Greek adults with a history of overweight/obesity who had achieved significant weight loss. Using the Total Mediterranean Lifestyle Index (total-MLI), the study assessed factors like diet, physical activity, and sleep quality. The findings revealed higher adherence to a Mediterranean lifestyle significantly correlated with sustained weight loss. Like most epidemiological dietary studies, including the ones mentioned earlier, the study’s cross-sectional design limits its ability to infer causality. Yet, the comprehensive approach to lifestyle assessment and the focused sample contribute meaningful insights into weight loss maintenance strategies. This study underscores the potential role of a holistic Mediterranean lifestyle in supporting long-term weight management.

“Its holistic approach to nutrition and adaptability make it an excellent option for anyone looking to improve their health sustainably and enjoyably.”

In addition to its health benefits, the Mediterranean diet is eco-friendly. A study led by Lora Iannotti, a public health researcher at Washington University in St. Louis, and published in Nature in 2021, focused on developing a nutritious and sustainable diet, addressing environmental and health concerns globally. This research, encompassing various countries from Kenya to Sweden, was part of a broader effort by academic investigators, the United Nations, and international funders to identify diets which are beneficial for human health and for the planet. A key finding of the study was the recommendation of the EAT–Lancet Commission on Food, Planet, Health for a ‘flexitarian’ diet, emphasizing plant-based foods with occasional meat or fish, as a sustainable dietary choice.

The Mediterranean diet concept of a largely plant-based diet in addition to seafood with minimal amounts of red meat, sugar and ultra-processed foods is supported by a number of large epidemiological studies. It is consistent with the evidence from microbiome studies that have shown that such a diet is also associated with a high diversity and richness of the gut microbiota. The Mediterranean diet concept is not just a trend like so many fad diets, but a lifestyle choice promoting personal health and environmental sustainability. Its holistic approach to nutrition and adaptability make it an excellent option for anyone looking to improve their health sustainably and enjoyably. The Mediterranean diet is described in detail in Dr. Mayer’s new recipe book Interconnected Plates, which demonstrates the unique mix of tradition, science, and enjoyment of food. This recipe book shows simple ways to translate this science into 55+ daily meals. For more details, check it out here!