According to a new report some components of a Mediterranean diet may be more vital to good health than others.

Although earlier research had indicated that the typical Mediterranean diet was linked to a longer life, it has now been found that certain aspects of the diet and not the whole are what increase chances of living long.

High consumption of vegetables, fruits, nuts and olive oil, low consumption of meat, and moderate consumption of alcohol may be more linked to longevity. Eating high quantities of fish and seafood and limiting dairy intake however did not seem to effect longevity.

In a study researchers at the University of Athens Medical School studied 23,349 men and women who were participating in the European Prospective Investigation into Cancer and Nutrition. None of the participants had previously been diagnosed with cancer, heart disease, or diabetes.

The participant's diets were closely monitored and rated according to how closely they followed the traditional Mediterranean diet. During the follow-up period of 8.5 years there were 652 deaths among 12,694 participants who had lower Mediterranean diet scores of 0-4 and 423 deaths among the 10,655 participants who had higher scores of at least 5.

The researchers found that those with the higher scores were more likely to be alive at the end of the study as compared to those with a low score. The factors in the diet that played a stronger role than others were found to be moderate alcohol consumption, low consumption of meat and meat products, high vegetable consumption, high fruit and nut consumption, high monounsaturated to saturated fat ratio, and high legume consumption.

The study authors said the beneficial effects of the diet were negated when factors of heavy vegetable consumption, light meat intake or moderate drinking were removed from the diet. The combination of consuming a diet that was rich in vegetables and olive oil showed maximum health benefits.

The report is in the June 23 online edition of BMJ.