The Seven Countries study in the 1960s which was an analysis done by Dr Ancel Keys was showed that populations in the Mediterranean region experienced lower coronary heart disease (CHD) mortality. He attributed this to their diet. Later on further observational studies confirmed the benefits of adherence to a Mediterranean dietary pattern on cardiovascular disease (CVD) risk factors.
But is there objective hard evidence? True clinical benefits to this diet is more limited – which is highly problematic as this is the paradigm upon which modern day diets are built. This Cochrane Database of Systematic Reviews published 2019, looked at this diet specifically.
They analysed a comprehensive database on the Mediterranean diet and concluded that there is no benefit for this method of eating for preventing heart disease (primary prevention) and for those that have developed heart disease (secondary prevention).