Randomized controlled trials, in which people are randomly assigned to a particular treatment and then monitored over time, are considered by many to be the “gold standard” of nutrition research. In this randomized controlled trial, 1,002 Spanish adults (average age 59) with heart disease were randomly assigned to a Mediterranean diet or a control diet (which differed by emphasizing lean meats and fish and low-fat dairy, and restricting fatty fish, nuts and olive oil) and followed for 7 years. Those eating a Mediterranean diet were 25-29% less likely to have a major cardiovascular event (such as a heart attack or stroke) than those eating the control diet, with the relationship being especially strong in men. These findings are consistent with previous research noting the cardioprotective benefits of a Mediterranean diet.
Lancet. 2022 May 4;S0140-6736(22)00122-2. doi: 10.1016/S0140-6736(22)00122-2. (Delgado-Lista J et al.)