The findings show that the Mediterranean oil mounts a multi-pronged attack on the tumors, stunting their growth, driving their cells to implode and protecting against potentially-cancerous damage to DNA.
Spanish scientists from the Universitat Autonoma de Barcelona conducted experiments on rats, which showed that olive oil thwarts a gene that drives the growth of breast tumors. It also protects DNA from damage that can lead to cancer.
According to researcher Eduard Escrich, only long-term use will give results and recommends adding 50ml, or 10 teaspoons, of high quality, extra-virgin olive oil in daily diets.
Another Spanish research has found that apart from cutting risks of breast cancer, olive oil "turns down" genes linked to hardening of arteries and heart disease.
"Knowing which genes can be modulated by diet in a healthy way can help people select healthy foods," said Maria Isabel Covas, a researcher of the Insitut Municial d'Investigacio Medica in Barcelona.
Gerald Weissmann, editor-in-chief of the journal of the Federation of American Societies for Experimental Biology (FASEB), which published the finding, said, "This study is ground-breaking because it shows that olive oil and a Mediterranean diet affect our bodies in a far more significant way than previously believed."
The Mediterranean diet has previously been credited with protecting against all major diseases including cancer, heart disease, Alzheimer's and Parkinson's.
The health benefits come from it as the diet is high in fruit, vegetables, fish, nuts, whole grains and healthy fats such as those in olive oil, while low in red meat and dairy products.
From the April 4, 2011, Prepared Foods E-dition