Epidemiological studies showed that olive oil exercised a protective effect against some malignant tumors (breast, prostate, digestive tract, etc.).
We know now that olive oil allows decreasing the risk of developing breast cancer. This effect was demonstrated within the framework of various researches.
The adoption of a healthy diet based on olive oil as a source of fat, would allow reducing considerably the incidence of a tumor because the cellular mutation that is at the origin of cancer is partially due to the consumption of toxic matter (toxin) which attack the DNA.
The passage of this toxin in the liver produces free radicals that might attack the DNA. To fight these radicals the body needs vitamins and antioxidants as those contained in olive oil.
The protective effect of olive oil against colon cancer has been demonstrated recently.
The metabolic impact of fat has been the object of several researches in recent years, particularly the role of olive oil consumption in preventing chronic liver disease and intestinal Crohn's disease.
The conducted researches have highlighted the positive effects of olive oil on precancerous lesions.
After analyzing the effect of three types of diets, different conclusions were drawn: A diet rich in olive oil significantly reduced the number of initial lesions of carcinogenesis; that was also the case of tumors that were less aggressive.
This positive effect could be related to the effect of oleic acid, the major monounsaturated fatty acid in olive oil. It has indeed been verified that oleic acid helps to reduce the production of prostaglandins derived from arachidonic acid, which plays an important role in the appearance and development of tumors.
However, it is not excluded that other compounds of olive oil, such as antioxidants, flavonoids, polyphenols and squalene, also have a positive effects. It is now known that squalene is good to the skin and that it reduces the incidence of melanomas.
In addition, olive oil, thanks to its palatability, facilitates the consumption of green vegetables and pulses whose positive effects in the prevention of cancer have been amply demonstrated.
Otherwise, the protective effect of olive oil against childhood leukemia and other types of cancer notably squamous cell cancer of the esophagus are under serious consideration. The results obtained so far are very promising.