The study, published in Seminars in Cancer Biology, showed nutrients from Hass avocados -- the most readily available -- killing some cancer cells and preventing precancerous cells from developing into actual cancers.

"As far as we know, this is the first study of avocados and oral cancer," lead author Steven D'Ambrosio, of Ohio State University's Comprehensive Cancer Center, said in a statement. "Our study focuses on oral cancer, but the findings might have implications for other types of cancer. These are preliminary findings, and more research is needed."

D'Ambrosio, who collaborated with researchers in Ohio State's College of Pharmacy, found that phytochemicals extracted from avocados target multiple signaling pathways and increase the amount of reactive oxygen within the cells, leading to cell death in precancerous cell lines. The phytochemicals did not, however, harm normal cells.

Avocados are full of beneficial antioxidants and phytonutrients, including vitamin C, folate, vitamin E, fiber and unsaturated fats, D'Ambrosio says.