The Mediterranean diet is a concept first proposed in 1975 by the American biologist Ancel Keys and chemist Margaret Keys. The diet took inspiration from the eating habits and

traditional food Traditional foods are foods and Dish (food), dishes that are passed on through generations or which have been consumed for many generations. Traditional foods and dishes are traditional in nature, and may have a historic precedent in a national ...

typical of Crete, much of the rest of Greece, and southern Italy, and formulated in the early 1960s. It is distinct from Mediterranean cuisine, which covers the actual cuisines of the Mediterranean countries, and from the Atlantic diet of northwestern Spain and Portugal. While inspired by a specific time and place, the "Mediterranean diet" was later refined based on the results of multiple scientific studies. This approach emphasizes a plant-based diet, focusing on unprocessed cereals,

legume Legumes are plants in the pea family Fabaceae (or Leguminosae), or the fruit or seeds of such plants. When used as a dry grain for human consumption, the seeds are also called pulses. Legumes are grown agriculturally, primarily for human consum ...

vegetable Vegetables are edible parts of plants that are consumed by humans or other animals as food. This original meaning is still commonly used, and is applied to plants collectively to refer to all edible plant matter, including edible flower, flo ...

s, and

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

s. It also includes moderate consumption of

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

, dairy products (mostly

cheese Cheese is a type of dairy product produced in a range of flavors, textures, and forms by coagulation of the milk protein casein. It comprises proteins and fat from milk (usually the milk of cows, buffalo, goats or sheep). During prod ...

and

yogurt Yogurt (; , from , ; also spelled yoghurt, yogourt or yoghourt) is a food produced by bacterial Fermentation (food), fermentation of milk. Fermentation of sugars in the milk by these bacteria produces lactic acid, which acts on milk protein to ...

), and a low amount of red meat.

Olive oil Olive oil is a vegetable oil obtained by pressing whole olives (the fruit of ''Olea europaea'', a traditional Tree fruit, tree crop of the Mediterranean Basin) and extracting the oil. It is commonly used in cooking for frying foods, as a cond ...

has been studied as a potential health factor for reducing all-cause mortality and the risk of

chronic disease A chronic condition (also known as chronic disease or chronic illness) is a health condition or disease that is persistent or otherwise long-lasting in its effects or a disease that comes with time. The term ''chronic'' is often applied when the ...

s. The Mediterranean diet is associated with a reduction in all-cause mortality in

observational studies In fields such as epidemiology, social sciences, psychology and statistics, an observational study draws inferences from a sample to a population where the independent variable is not under the control of the researcher because of ethical conc ...

. A 2017 review provided evidence that the Mediterranean diet lowers the risk of

heart disease Cardiovascular disease (CVD) is any disease involving the heart or blood vessels. CVDs constitute a class of diseases that includes: coronary artery diseases (e.g. angina pectoris, angina, myocardial infarction, heart attack), heart failure, ...

and early death. The Mediterranean diet may help with weight loss in obese people. The Mediterranean diet is one of three healthy diets recommended in the 2015–2020 Dietary Guidelines for Americans, along with the DASH diet and vegetarian diet.

Health effects

A 2017 review found evidence that practice of a Mediterranean diet could lead to reduced risk of cardiovascular diseases, overall

cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...

incidence,

neurodegenerative diseases A neurodegenerative disease is caused by the progressive loss of neurons, in the process known as neurodegeneration. Neuronal damage may also ultimately result in their death. Neurodegenerative diseases include amyotrophic lateral sclerosis, mul ...

diabetes Diabetes mellitus, commonly known as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes is due to either the pancreas not producing enough of the hormone insulin, or the cells of th ...

, and early death. A 2018 review showed that practice of the Mediterranean diet may improve overall health status, such as reduced risk of non-infectious diseases, reduced total costs of living, and reduced costs for national

healthcare Health care, or healthcare, is the improvement or maintenance of health via the preventive healthcare, prevention, diagnosis, therapy, treatment, wikt:amelioration, amelioration or cure of disease, illness, injury, and other disability, physic ...

. A 2016 review found similar weight loss as other diets. A 2019 Cochrane review found that there is still uncertainty regarding the effects of Mediterranean‐style diet advice on cardiovascular disease occurrence and risk factors in people both with and without existing cardiovascular disease. The US 2015–2020 national guidelines devised a "Healthy Mediterranean-Style Eating Pattern", assessed against and mirroring the Mediterranean diet patterns and its positive health outcomes. It was designed from the "Healthy U.S.-Style Eating Pattern", but it contains more fruits and seafood, and less dairy. In the 2020s, research on the Mediterranean diet indicates that a Mediterranean diet may contribute to health.

Cardiovascular disease

The Mediterranean diet is included among dietary patterns that may reduce the risk of cardiovascular diseases. A 2013 Cochrane review found limited evidence that a Mediterranean diet favorably affects cardiovascular

risk factor In epidemiology, a risk factor or determinant is a variable associated with an increased risk of disease or infection. Due to a lack of harmonization across disciplines, determinant, in its more widely accepted scientific meaning, is often use ...

s. A 2013 meta-analysis compared Mediterranean,

vegan Veganism is the practice of abstaining from the use of animal products and the consumption of animal source foods, and an associated philosophy that rejects the commodity status of animals. A person who practices veganism is known as a ve ...

, vegetarian, low-glycemic index, low-carbohydrate, high-fiber, and high-protein diets with control diets. The research concluded that Mediterranean, low-carbohydrate, low-glycemic index, and high-protein diets are effective in improving markers of risk for cardiovascular disease and diabetes, while there was limited evidence for an effect of vegetarian diets on glycemic control and lipid levels unrelated to weight loss. However, more cautious reviews arose in early 2016, raising concerns about the quality of previous

systematic review A systematic review is a scholarly synthesis of the evidence on a clearly presented topic using critical methods to identify, define and assess research on the topic. A systematic review extracts and interprets data from published studies on ...

s examining the impact of a Mediterranean diet on cardiovascular risk factors. These reviews insisted upon the need for further standardized research, stating that the evidence for possible prevention of cardiovascular disease by the diet was "limited and highly variable". Reviews in 2016-17 reached similar conclusions about the ability of a Mediterranean diet to improve cardiovascular risk factors, such as lowering the risk for

hypertension Hypertension, also known as high blood pressure, is a Chronic condition, long-term Disease, medical condition in which the blood pressure in the artery, arteries is persistently elevated. High blood pressure usually does not cause symptoms i ...

and other cardiovascular diseases. A Mediterranean diet is recommended as a means of lowering

Apolipoprotein B Apolipoprotein B (ApoB) is a protein that in humans is encoded by the gene. Its measurement is commonly used to detect the risk of Atherosclerosis, atherosclerotic Coronary artery disease, cardiovascular disease. Isoforms The protein occur ...

. The Mediterranean diet is low in saturated fat with high amounts of monounsaturated fat and

dietary fiber Dietary fiber (fibre in English in the Commonwealth of Nations, Commonwealth English) or roughage is the portion of plant-derived food that cannot be completely broken down by human digestive enzymes. Dietary fibers are diverse in chemical co ...

. One possible factor is the potential health effects of olive oil in the Mediterranean diet. Olive oil contains monounsaturated fats, most notably

oleic acid Oleic acid is a fatty acid that occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish due to the presence of impurities. In chemical terms, oleic acid is cl ...

, which is under clinical research for its potential health benefits. The

European Food Safety Authority The European Food Safety Authority (EFSA) is the agency of the European Union (EU) that provides independent scientific advice and communicates on existing and emerging risks associated with the food chain. EFSA was established in February 2002 ...

Panel on Dietetic Products, Nutrition and Allergies approved health claims on olive oil, for protection by its

polyphenol Polyphenols () are a large family of naturally occurring phenols. They are abundant in plants and structurally diverse. Polyphenols include phenolic acids, flavonoids, tannic acid, and ellagitannin, some of which have been used historically as ...

s against oxidation of blood lipids and for the contribution to the maintenance of normal blood LDL-cholesterol levels by replacing saturated fats in the diet with oleic acid (Commission Regulation (EU) 432/2012 of 16 May 2012). A 2014 meta-analysis concluded that an elevated consumption of olive oil is associated with reduced risk of all-cause mortality, cardiovascular events and stroke, while monounsaturated fatty acids of mixed animal and plant origin showed no significant effects. The

American Heart Association The American Heart Association (AHA) is a nonprofit organization in the United States that funds cardiovascular medical research, educates consumers on healthy living and fosters appropriate Heart, cardiac care in an effort to reduce disability ...

discussed the Mediterranean diet as a healthy dietary pattern that may reduce the risk of

cardiovascular disease Cardiovascular disease (CVD) is any disease involving the heart or blood vessels. CVDs constitute a class of diseases that includes: coronary artery diseases (e.g. angina, heart attack), heart failure, hypertensive heart disease, rheumati ...

s. A 2023 review found evidence for a reduction of mortality and cardiovascular disease risk in women on a Mediterranean-type diet.

Diabetes

In 2014, two meta-analyses found that the Mediterranean diet was associated with a decreased risk of

type 2 diabetes Type 2 diabetes (T2D), formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent ...

, findings similar to those of a 2017 review. The American Diabetes Association and a 2019 review indicated that the Mediterranean diet is a healthy dietary pattern that may reduce the risk of diabetes.

Cancer

meta-analysis Meta-analysis is a method of synthesis of quantitative data from multiple independent studies addressing a common research question. An important part of this method involves computing a combined effect size across all of the studies. As such, th ...

in 2008 found that strictly following the Mediterranean diet was correlated with a decreased risk of dying from cancer by 6%. Another 2014 review found that adherence to the Mediterranean diet was associated with a decreased risk of death from cancer. A 2017 review found a decreased rate of cancer, although evidence was weak. An updated review in 2021 found that the Mediterranean diet is associated with a 13% lower risk of cancer mortality in the general population.

Weight loss in obesity

Overweight adults who adopt Mediterranean diets may lose weight by consuming fewer calories. A 2019 review found that the Mediterranean diet may help obese people lower the quantity and improve the nutritional quality of food intake, with an overall effect of possibly losing body weight.

Cognitive ability

A 2016 systematic review found a relation between greater adherence to a Mediterranean diet and better cognitive performance; it is unclear if the relationship is causal. According to a 2013 systematic review, greater adherence to a Mediterranean diet is correlated with a lower risk of

Alzheimer's disease Alzheimer's disease (AD) is a neurodegenerative disease and the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems wit ...

and slower cognitive decline. Another 2013 systematic review reached similar conclusions, and also found a negative association with the risk of progressing from mild cognitive impairment to Alzheimer's, but acknowledged that only a small number of studies had been done on the topic.

Major depressive disorder

There is a correlation between adherence to the Mediterranean diet and a lower risk of depression. Studies on which these correlations are made are observational and do not prove cause and effect.

Gluten

As the Mediterranean diet usually includes products containing

gluten Gluten is a structural protein naturally found in certain Cereal, cereal grains. The term ''gluten'' usually refers to the elastic network of a wheat grain's proteins, gliadin and glutenin primarily, that forms readily with the addition of water ...

, such as pasta and bread, increasing use of the diet may have contributed to the growing rate of gluten-related disorders.

Dietary components

There are variations of the "Mediterranean diets" in different countries and among the individual populations of the Mediterranean basin, due to ethnic, cultural, economic and religious diversities. The "Mediterranean diet" as defined by dietitians generally includes the following components, which are not typical of diets in the Mediterranean Basin: * High intakes of

olive oil Olive oil is a vegetable oil obtained by pressing whole olives (the fruit of ''Olea europaea'', a traditional Tree fruit, tree crop of the Mediterranean Basin) and extracting the oil. It is commonly used in cooking for frying foods, as a cond ...

(as the principal source of fat), and a plant-based diet: vegetables (including leafy green vegetables, onions, garlic, tomatoes, and peppers), fresh fruits (consumed as desserts or snacks), cereals (mostly

whole grain A whole grain is a grain of any cereal and pseudocereal that contains the endosperm, germ, and bran, in contrast to refined grains, which retain only the endosperm. As part of a general healthy diet, consumption of whole grains is associated ...

s), nuts, and legumes. * Moderate intakes of fish and other

seafood Seafood is any form of Marine life, sea life regarded as food by humans, prominently including Fish as food, fish and shellfish. Shellfish include various species of Mollusca, molluscs (e.g., bivalve molluscs such as clams, oysters, and mussel ...

, poultry, eggs,

dairy product Dairy products or milk products are food products made from (or containing) milk. The most common dairy animals are cow, water buffalo, goat, nanny goat, and Sheep, ewe. Dairy products include common grocery store food around the world such as y ...

s (primarily cheese and yogurt), and red wine. * Low intakes of red meat, processed meat, refined carbohydrates, and sweets. These proportions are sometimes represented in the Mediterranean Diet Pyramid. In a diet with roughly this composition, the fat content accounts for 25% to 35% of the total intake of

calorie The calorie is a unit of energy that originated from the caloric theory of heat. The large calorie, food calorie, dietary calorie, kilocalorie, or kilogram calorie is defined as the amount of heat needed to raise the temperature of one liter o ...

s, while the amount of saturated fat is, at most, 8% of the calorie content. Some cuisines of the Mediterranean region are not fully consistent with Mediterranean diet guidelines. For instance, olive oil is not the staple fat in the cuisines of all countries which border the Mediterranean: in northern and central Italy, lard and

butter Butter is a dairy product made from the fat and protein components of Churning (butter), churned cream. It is a semi-solid emulsion at room temperature, consisting of approximately 81% butterfat. It is used at room temperature as a spread (food ...

are commonly used in cooking, and olive oil is reserved for dressing salads and cooked vegetables;Massimo Alberini, Giorgio Mistretta, ''Guida all'Italia gastronomica'', Touring Club Italiano, 1984 in both

North Africa North Africa (sometimes Northern Africa) is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of t ...

and the

Middle East The Middle East (term originally coined in English language) is a geopolitical region encompassing the Arabian Peninsula, the Levant, Turkey, Egypt, Iran, and Iraq. The term came into widespread usage by the United Kingdom and western Eur ...

, sheep's tail fat and rendered butter ( ''samna'') are traditional staple fats.

Environmental effects

Consuming a Mediterranean diet or plant-based diet may contribute to improving environmental and agricultural sustainability, possibly due to lower use of dairy products, ruminant meat, and ultra-processed foods. The environmental impact and amount of energy needed to feed livestock exceeds its nutritional value. In a 2014 lifecycle analysis of

greenhouse gas emissions Greenhouse gas (GHG) emissions from human activities intensify the greenhouse effect. This contributes to climate change. Carbon dioxide (), from burning fossil fuels such as coal, petroleum, oil, and natural gas, is the main cause of climate chan ...

, researchers found that a Mediterranean-like diet may reduce food production emissions below those of an omnivorous diet for 2050, with a

per capita ''Per capita'' is a Latin phrase literally meaning "by heads" or "for each head", and idiomatically used to mean "per person". Social statistics The term is used in a wide variety of social science, social sciences and statistical research conte ...

reduction of 30%.

History and research

The concept of Mediterranean diet was first publicized in 1975 by the American biologist Ancel Keys and chemist Margaret Keys (a husband and wife team), but failed to gain widespread recognition until the 1990s. Objective data showing that the Mediterranean diet is healthy originated from results of epidemiological studies in

Calabria Calabria is a Regions of Italy, region in Southern Italy. It is a peninsula bordered by the region Basilicata to the north, the Ionian Sea to the east, the Strait of Messina to the southwest, which separates it from Sicily, and the Tyrrhenian S ...

Naples Naples ( ; ; ) is the Regions of Italy, regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 908,082 within the city's administrative limits as of 2025, while its Metropolitan City of N ...

and

Madrid Madrid ( ; ) is the capital and List of largest cities in Spain, most populous municipality of Spain. It has almost 3.5 million inhabitants and a Madrid metropolitan area, metropolitan area population of approximately 7 million. It i ...

, confirmed later by the Seven Countries Study first published in 1970, and a book-length report in 1980. The most commonly understood version of the Mediterranean diet was presented by, among others, Walter Willett and colleagues of the

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

School of Public Health since the mid-1990s. The Mediterranean diet is based on a paradox: although the people living in Mediterranean countries tend to consume relatively high amounts of fat, they have far lower rates of

than in countries such as the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

where similar levels of fat consumption are found. A parallel phenomenon is known as the French paradox. By 2011, the Mediterranean diet was included by some authors as a

fad diet A fad diet is a diet that is popular, generally only for a short time, similar to fads in fashion, without being a standard scientific dietary recommendation, and often making unreasonable claims for fast weight loss or health improvements; ...

promoted for losing weight. Since about 2016, the

and American Diabetes Association have recommended the Mediterranean diet as a healthy dietary pattern that may reduce the risk of

s and

, respectively. The

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

National Health Service The National Health Service (NHS) is the term for the publicly funded health care, publicly funded healthcare systems of the United Kingdom: the National Health Service (England), NHS Scotland, NHS Wales, and Health and Social Care (Northern ...

also recommends a Mediterranean diet to reduce cardiovascular disease risk."Mediterranean diet"
uhcw.nhs.uk. Retrieved 22 October 2023. In 2018, the '' European Journal of Public Health'' questioned the value of the traditional Mediterranean diet due to homogenization of dietary choices and food products in the global economy. Despite this,

clinical research Clinical research is a branch of medical research that involves people and aims to determine the effectiveness (efficacy) and safety of medications, devices, diagnostic products, and treatment regimens intended for improving human health. The ...

activity remained high, with favorable outcomes reported for various disease conditions, such as

metabolic syndrome Metabolic syndrome is a clustering of at least three of the following five medical conditions: abdominal obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum high-density lipoprotein (HDL). Metabolic syndro ...