Anti cancer action is actually related to the polyphenols contained in the berries, rather than in their antioxidant potential, as is commonly assumed. A diet containing a high proportion of strawberries or raspberries (5% or more of total diet) in animals, has been found to significantly decrease the number of esophageal tumors triggered by NMBA, a known powerful carcinogen. Ellagic acid appears to prevent the activation of carcinogenic substances into cellular toxins, causing them to lose their ability to react with DNA and induce mutations capable of triggering the onset of cancer. In addition, strawberry also contains a kind of amine substance, which has good effect in the prevention of leukemia and other diseases related with blood.strawbrries