People who live in the Mediterranean countries have a lower incidence of cancer than Americans do because of the high levels of olive oil, fish, fresh fruits and vegetables in their diet. Studies have shown that the “good” fat and phenols in olive oil may help prevent colon, breast, skin, pancreatic, lung, and ovarian cancers. One study found that rats whose diets were supplemented with olive oil had less cancer-prone tissue and tumors than the rats consuming other oils. Antioxidants in olive oil attack harmful molecules that can damage/alter cells and lead to cancer. The unsaturated fat in the oil helps to kill off cancerous breast cells and to lower levels of the gene responsible for breast  cancer. “Olive oil from the Lakonia region is extracted primarily from the  Koroneiki olive variety which has one of the highest levels of polyphenols, the  antioxidant that prevents the development of cancer.”