The Mediterranean diet is a diet inspired by the eating habits of Spain, Italy and Greece in the 1960s. The principal aspects of this diet include proportionally high consumption of olive oil, legumes, unrefined cereals, fruits, and vegetables, moderate to high consumption of fish, moderate consumption of dairy products (mostly as cheese and yogurt), moderate wine consumption, and low consumption of non-fish meat products. Olive oil has been studied as a potential health factor for reducing all-cause mortality and the risk of chronic diseases.
The Mediterranean diet is associated with a reduction in all-cause mortality in observational studies. There is some evidence that the Mediterranean diet lowers the risk of heart disease and early death, although a 2019 review determined that the evidence had low quality and was uncertain. The American Heart Association and American Diabetes Association recommend the Mediterranean diet as a healthy dietary pattern that may reduce the risk of cardiovascular diseases and type 2 diabetes, respectively. 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 US Dietary Guidelines, which also include the DASH diet or a vegetarian diet.
A 2017 review found evidence that practice of a Mediterranean diet could lead to a decreased risk of cardiovascular diseases, overall cancer incidence, neurodegenerative diseases, diabetes, and early death. A 2018 review showed that practice of the Mediterranean diet may improve overall health status, such as reduced risk of non-communicable diseases, reduced total costs of living, and reduced costs for national healthcare. A 2016 review found similar weight loss as other diets.
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.