The meta-analysis that pooled data from 12 international studies was conducted by researchers at the University of Florence and was published on 11th September in BMJ.
Previous research on the diet that is followed by populations bordering the Mediterranean Sea has suggested it protects against cardiovascular disease and cancer, but until this study, no research had yet pooled all the data available to examine the link to premature death and incidence of chronic diseases in the general population.
For the study, the authors systematically reviewed all the prospective cohort studies published since 1966 that have analysed links between following a Mediterranean diet, rates of death, and presence of chronic diseases in primary prevention settings. This came to a total of 12 studies covering over 1.5 million people whose dietary habits and health were followed for up to 18 years.
All the studies used an "adherence score" to represent how closely the participants followed the diet.
The results showed that:
• A cumulative analysis of data pooled from eight cohorts (total of 514,816 subjects and 33,576 deaths) examining overall deaths due to any cause against adherence to a Mediterranean diet showed that a two point increase in the adherence score was significantly associated with a 9 per cent reduced risk of death.
• The analyses also showed a beneficial link between greater adherence to a Mediterranean diet and deaths from cardiovascular diseases (9 per cent reduction) and cancer (6 per cent), and incidence of Parkinson's disease and Alzheimer's disease (13 per cent).
The authors concluded that:
"These results seem to be clinically relevant for public health, in particular for encouraging a Mediterranean-like dietary pattern for primary prevention of major chronic diseases."
The findings reinforce the current guidelines and recommendations from all major scientific institutions that encourage people to follow a Mediterranean-like diet to reduce their risk of major chronic diseases.
The researchers suggested that an "adherence score" based on how closely a Mediterranean diet is followed could be used as an effective prevention tool for reducing the risk of premature death in the general population.