The Mediterranean diet is a nutritional model that has been recognized by the international scientific community as one of the healthiest and most balanced diets in the world. Following a healthy diet like the Mediterranean diet is a simple and achievable way of looking after ourselves and preventing the development of cardiovascular disease, diabetes and different types of cancer, for example.

A study carried out and led by IMIM researchers has shown, for the first time, the potential therapeutic action of the traditional Mediterranean diet on cardioprotective HDL or “good cholesterol”. The team, coordinated by Dr. Montserrat Fitó of the IMIM Research Group on Cardiovascular Risk and Nutrition, concluded that following a Mediterranean diet, rich in virgin olive oil, improves the function of high-density lipoproteins (HDLs). That is to say, it helps the particles that transport “good cholesterol” to work better. This may be one of the reasons why following this diet prevents the development of cardiovascular disease.

HDLs and “Good Cholesterol”

The main function of HDLs is to remove the excess cholesterol from the arteries and transport it to the liver for excretion. Until now, the benefits to the function of “good cholesterol” had only been shown in some clinical trials with drugs, with surgical interventions or with interventions based on increasing the consumption of isolated foods but no studies had been done on what happened if the entire diet was modified.

In this study, the researchers compared two types of Mediterranean diet, one rich in olive oil and the other rich in nuts, with a low-fat diet and they saw that sticking to a traditional Mediterranean diet, especially when it was rich in olive oil, was associated with improved HDL functions. The biological functions of HDLs are, therefore, what help to explain its cardioprotective role, rather than the levels of “good cholesterol”.

The Study

To carry out this study, the researchers randomly chose a subsample of 296 volunteers from the PREDIMED (Prevention with the Mediterranean Diet) study and isolated the lipoproteins from the blood samples obtained before beginning the study and after a year of following the Mediterranean diet, and studied their main functions. The study opens up a broad range of possibilities, as it allows us to understand another physiological process that the Mediterranean diet is able to improve, as well as contributing to the discovery of new therapeutic targets to improve the functions of HDL.

This study has attracted the attention of the American Heart Association, the most important organization worldwide in cardiovascular health, as to date, no study of this type had been carried out, with such a large sample size and with a follow-up of a whole year.

Reference article

Hernáez A, Castañer O, Elosua R, Pintó X, Estruch R, Salas-Salvadó J, Corella D, Arós F, Serra-Majem L, Fiol M, Ortega-Calvo M, Ros E, Martínez-González MÁ, de la Torre R, López-Sabater MC, Fitó M. Mediterranean Diet Improves High-Density Lipoprotein Function in High-Cardiovascular-Risk Individuals: A Randomized Controlled Trial. Circulation 2017; 135(7): 633-643.