In this study, the first of its kind carried out in a UK population, the researchers found that healthy individuals with greater adherence to a Mediterranean-type diet had 6 to 16% lower risk of future cardiovascular disease compared to individuals who had poor adherence.
Dr Nita Forouhi, lead author from the Medical Research Council Epidemiology Unit at the University of Cambridge, UK, said: “We estimate that one in 25 of all new cardiovascular disease cases or one in eight cardiovascular deaths in our UK based study population could potentially be avoided if this population increased their adherence to the Mediterranean diet.”
The Mediterranean diet is typically high in fruits, vegetables, whole grains, nuts and olive oil, while low in red meats and moderate in dairy, fish, poultry and wine. The UK National Institute for Health and Care Excellence (NICE) recommends a Mediterranean style diet for people already diagnosed with cardiovascular disease to prevent further episodes of heart attack or stroke. However, the association of the Mediterranean diet with preventing cardiovascular disease in the first instance or preventing further episodes has not been examined in the UK until now.
Dr Forouhi adds: “The benefits of the Mediterranean diet for cardiovascular health are well documented in countries of the Mediterranean region, but this is the first study to evaluate this in the UK. If our findings are broadly representative of the overall UK population, then we can assume that higher level of adherence to the Mediterranean diet could have significant impact in lowering the cardiovascular disease burden in the UK.”
The researchers collected data from 23,902 initially healthy Britons taking part in the EPIC-Norfolk prospective cohort study. The participants’ diets were measured using food frequency questionnaires and participants were followed up for an average of 12 to 17 years to investigate the association between adherence to the Mediterranean diet and the occurrence of new-onset CVD and deaths during that time.
The Mediterranean diet was defined using a 15 point score based on guideline recommendations from a Mediterranean dietary pyramid published by the Mediterranean Diet Foundation. This is the first time these guidelines have been tested for their associations with health. There are other definitions of what constitutes a Mediterranean diet, but when alternative definitions were used in this study, the findings were broadly similar.
Dr Forouhi adds: “Encouraging greater adoption of the Mediterranean diet looks like a promising component of a of a wider strategy to help prevent cardiovascular disease, including other important factors such as not smoking and maintaining a healthy weight, blood cholesterol and blood pressure.”
The authors acknowledge that these findings are based on an observational study and so a cause and effect relationship cannot be assumed. However, they were careful to make comprehensive adjustments for lifestyle and other factors that could potentially distort the findings, and together with the consistency of results with other studies elsewhere, their current findings provide robust evidence for a link.
Dr Forouhi concludes: “Our study shows that higher versus lower adherence to a Mediterranean-type diet is linked with lower future CVD risk in the UK but our challenge now is to understand the social, economic and cultural factors that might support or prevent people being able to keep to this dietary pattern in the UK.”