EATING a Mediterranean-style diet helps you live longer by protecting against all the major chronic diseases, a study has shown. Those who eat lots of fresh fish, fruit, vegetables and whole grains are less likely to die prematurely, according to the research. The diet was also found to be an effective defence against heart disease, Parkinson's, Alzheimer's disease and cancer. Scientists looked at 12 international studies using a nine-point scale to assess how closely 1.5million volunteers stuck to the Mediterranean diet. Those with higher scores were shown to be less likely to die of any cause, or have a major chronic disease, says the study published today in the British Medical Journal Online First. The diet has been thought to improve heart health and stave off cancer because it is high in fruit, vegetables, fish, nuts, whole grains and healthy fats such as those in olive oil, while low in red meat and dairy products. Drinking alcohol, particularly red wine, is encouraged in moderation. Populations surrounding the Mediterranean Sea, such as Greece, Spain and Italy, tend to eat these foods. Researchers from the University of Florence, Italy, looked at the previous studies, which collectively included more than 1.5million participants. Their dietary habits and health were tracked for follow-up periods ranging from three to 18 years. Scientists used an 'adherence score' to estimate how well volunteers followed to the diet. Those who stuck closely to it scored between seven and nine points, while volunteers who didn't follow the diet could have scored as low as zero. The researchers found that those who stuck rigidly to a Mediterranean diet had significant improvements in their health, including a drop of 9 per cent in overall deaths and a 9 per cent drop in heart deaths. They found a 13 per cent reduction in cases of Parkinson's and Alzheimer's disease, and a 6 per cent fall in cancer. Lead researcher Dr Francesco Sofi said all major scientific institutions recommend a Mediterranean diet for prevention of major chronic diseases. He said: 'These results seem to be clinically relevant in terms of public health, particularly for reducing the risk of premature death in the general population.' Earlier this year, U.S. researchers found that sticking to a Mediterranean diet could help stave off premature death. British, Greek and Spanish scientists found it helped prevent the development of asthma and respiratory allergies in children. Last year, U.S. researchers also found that eating a Mediterranean diet could reduce the risk of developing Alzheimer's.