A Mediterranean diet is generally defined as one rich in plant foods and fish, low in meat and dairy products, and with a high ratio of monounsaturated fatty acids to polyunsaturated fatty acids.
The first study concluded that individuals aged 70 to 90 years old who adhered to a Mediterranean-type diet and led a fairly healthy life had a more than 50 per cent lower death rate than those who did not.
Kim Knoops and colleagues from Wageningen University, the Netherlands, investigated the single and combined effect of a Mediterranean diet, being physically active, moderate alcohol use, and nonsmoking on all-cause and cause-specific deaths in elderly individuals.
The study called HALE (Healthy Ageing: a Longitudinal study in Europe), was conducted between 1988 and 2000 and included 1,507 healthy men and 832 women, in 11 European countries.
The researchers found that adhering to a Mediterranean diet was associated with a 23 per cent lower risk of all-cause death; moderate alcohol use, a 22 per cent lower risk; physical activity, a 37 per cent lower risk; and nonsmoking, a 35 per cent lower risk.
Similar results were observed for death from coronary heart disease, cardiovascular diseases, and cancer. Having all four low risk factors lowered the all-cause death rate by 65 per cent.
The second study was led by Katherine Esposito and colleagues from the Second University of Naples, Italy, who demonstrated that a Mediterranean-style diet had beneficial effects the metabolical syndrome - condition characterised by obesity, high blood pressure and increased blood sugar.
Recent estimates indicate that the metabolic syndrome is highly prevalent in the United States in particular with an estimated 24 per cent of the adult population affected.
The randomized trial was conducted from June 2001 to January 2004 at a university hospital in Italy among 180 patients (99 men and 81 women) suffering from the metabolic syndrome.
Half the patients followed a Mediterranean-style diet, while the remaining 90 followed a "prudent diet", made up of 50-60 per cent carbohydrates, 15-20 per cent proteins, and less than 30 per cent total fat.
The researchers found that after two years, patients in the Mediterranean diet group had significant decreases in body weight, blood pressure, levels of glucose, insulin, total cholesterol, and triglycerides and a significant increase in levels of high-density lipoprotein cholesterol.
Moreover, only forty patients consuming the Mediterranean regime still had features of the metabolic syndrome, compared with 78 patients following the control diet, and the prevelance of the metabolic syndrome was almost halved in the Mediterranean group.
"The results of this study represent the first demonstration, to our knowledge, that a Mediterranean-style diet rich in whole grains, fruits, vegetables, legumes, walnuts, and olive oil might be effective in reducing both the prevalence of the metabolic syndrome and its associated cardiovascular risk," the authors concluded.
Both studies appear in the 22/29 September issue of JAMA.