PARIS (AFP) - The Mediterranean diet, which is famously beneficial for the cardiovascular system, also helps protect against diabetes, according to a paper published online Thursday by the British Medical Journal. The mainstays of the Mediterranean diet are olive oil, fish, grains, fruit, nuts and vegetables, usually supplemented by a modest amount of red wine. Meat and dairy products have only a minor role. Researchers at the University of Navarra in northern Spain recruited 13,753 people with graduate-level education between December 1999 and November 2007 and who had no history of diabetes when they were enrolled. Their health and dietary habits were then tracked in detail over the following months and years. During the follow-up period an average of 4.4 years over the range of participants 103 people became diagnosed with Type 2 diabetes, with a large preponderance of cases among those who did not follow the basics of the Med diet. Those who adhered to the diet most strictly enjoyed a relative reduction of 83 percent in the risk of diabetes. Intriguingly, many people in this group also had the biggest accumulation of risk factors for the disease they were older, were fatter, had a family history of diabetes, more sedentary lifestyle or were ex-smokers. But they appear to have been shielded by the diet, the authors say. Type 2 diabetes has become an epidemic in developed and developing countries, with the blame being pinned on a switch to sugary and fatty diets and sedentary lifestyle. A less common form of diabetes called Type 1 is caused by permanent destruction of insulin-producing beta cells in the pancreas, and usually occurs early in life. Without treatment by synthetic doses of insulin, diabetes can result in kidney failure, blindness, heart disease and death. The International Diabetes Federation forecasts the number of cases including many adolescents will explode from 246 million today to 380 million by 2025. Many previous studies have praised the Mediterranean diet for cardiac and vascular health, and a paper published in January this year in the British journal Thorax found that women who followed the diet while pregnant may also protect their baby from childhood asthma and allergy.