The claim came after conclusions were published by a group of 300 scientists attending a weekend conference on its life-giving properties in the southern Spanish city of Jaen.
"The Mediterranean dietary pattern is being rediscovered as the one that best fulfils the need for nourishment and pleasure," the scientists said on Tuesday, while gathered in the world's biggest olive oil production centre.
"One of the most well-known and important characteristics of the Mediterranean diet is the presence of virgin oil as the principal source of energy from fat," the scientists added.
Such a diet "is a healthy dietary model to achieve a healthy aging and to prevent the most important causes of morbidity and mortality around the world," the conference concluded.
According to the scientists, the Mediterranean diet is associated with a low cardiovascular risk and it aids a healthy metabolism after eating.
With its monounsaturated fat intake, olive oil appears to be associated with a reduced risk of age-related cognitive decline, the conference noted.
Stop heart disease
Commercial olive oil comes in several categories but extra virgin olive oil is regarded as the most nutritious.
At the first international congress on olive oil and its role in promoting good health, scientists said on Saturday that a vitamin-filled Mediterranean diet based on olive oil, fish and fresh vegetables helped to keep Spanish rates of heart disease some two-thirds lower than in northern Europe.
It is also seen as a key weapon in warding off Alzheimer's disease, cardiovascular ailments and cancer.
"We don't even know 10% of its benefits," said congress chairman Francisco Perez.