Orange juice has many potential positive effects when it comes to cancer, particularly because it is high in antioxidants from flavonoids such as hesperitin and naringinin. Evidence from previous in vitro studies has indicated that orange juice can reduce the risk of leukemia in children, as well as aid in chemoprevention against mammary, hepatic, and colon cancers. Biological effects of orange juice in vitro are largely influenced by the juice’s composition, which is dependent on physiological conditions of the oranges such as climate, soil, fruit maturation, and storage methods post-harvest.
The researchers acknowledge potential toxicity from orange juice if consumed in excess amounts — especially for children, hypertensive, kidney-compromised, and diabetics. Excessive drinking of orange juice for individuals from these groups has the potential to create noxious effects, hyperkalemia, and has been associated with both food allergies and bacterial outbreaks in cases where the juice was unpasteurized. "Excessive intake of any food, even for the healthiest, can lead to oxidative status imbalance," wrote the researchers.
Further research is highly recommended to determine the biological connection between orange juice and cancer chemoprevention. Issues such as the type of cultivar and the amount consumed will also need clarification.
Overall, the review article summarizes several biological effects of orange juice that can contribute to chemoprevention, including antioxidant, antimutagenic and antigenotoxic, cytoprotective, hormonal, and cell signaling modulating effects. Orange juice has antimicrobial and antiviral action and modulates the absorption of xenobiotics. "OJ could contribute to chemoprevention at every stage of cancer initiation and progression," the researchers explained. "Among the most relevant biological effects of OJ is the juice’s antigenotoxic and antimutagenic potential, which was shown in cells in culture and in rodents and humans."
source : http://www.sciencedaily.com/releases/2013/09/130913124127.htm