The health benefits of the Mediterranean diet can be largely ascribed to the nutraceutical properties of extra-virgin olive oil (EVOO). Mono-unsaturated fatty acids and various phenolic compounds, such as oleocanthal, oleuropein, hydroxytyrosol, and tyrosol, are the main nutraceutical substances of EVOO. These substances have been suggested to have the ability to modulate aging-associated processes. In experimental models, it has been shown that EVOO with high concentrations of polyphenols has anti-inflammatory and anti-oxidant properties. Indeed, it was observed that hydroxytyrosol and oleocanthal inhibit the cyclooxygenases (COX-1 and -2) responsible for prostaglandin production; oleuropein is a radical scavenger that blocks the oxidation of low-density lipoproteins. Due to the relevance of olive oil in the economy of Sicily, our group has been funded to assess the nutraceutical properties of different kinds of olive oil. Indeed, the aim of the study is to evaluate effects of EVOOs, with low and high polyphenols content, on immuno-inflammatory and oxidative stress responses in young and old people. A further objective of our group is to evaluate effects of EVOO, with low and high polyphenol content, on the expression of genes encoding proteins that take part in the insulin/insulin-like growth factor-1 signaling pathway involved in longevity. The results of the study will be useful for producing olive oil enriched in nutraceutical properties that may be likely helpful in the prevention of age-related diseases.