A new review from Brazil concludes that orange juice has many positive effects that may aid cancer prevention, particularly because of its antioxidants. On the other hand, excessive consumption of orange juice may have harmful effects.
The review analyzed available data from in vitro, animal and human (observational and clinical) studies investigating potential cancer-preventing effects of orange juice (1). The data analysis showed that orange juice had many potential positive effects aiding cancer prevention, particularly because of its high content of antioxidants such as vitamin C and flavonoids. Several biological effects of orange juice may contribute to prevention, including antioxidant, antimutagenic and antigenotoxic, cell protective, hormonal, and cell sig-naling modulating effects. Among the most relevant biological effects is the juice’s antigenotoxic and anti-mutagenic potential, which was shown in cell cultures, animals and humans. Results from in vitro studies have indicated that orange juice can reduce the risk of leukemia in children and can aid in preventing mammary, hepatic and colon cancers. Orange juice seemed to contribute to prevention at every stage of cancer initiation and progression. In addition, it modulated the absorption of xenobiotics, such as drugs.
Some study data indicated that orange juice, if consumed in excess amounts, may have harmful effects – especially for children, as well as hypertensive, kidney-compromised, and diabetic patients – potentially because it generates an imbalance of the organism’s oxidative status. For individuals from these groups, excessive drinking of orange juice seems to have the potential to create harmful effects, such as hyper-kalemia (elevated potassium concentration in the blood), and has been associated with both food allergies and bacterial outbreaks in cases where the juice was unpasteurized.
The researchers commented that randomized controlled trials in humans are needed to establish to what extent orange juice has a preventive effect on cancer risk, i.e. in terms of its quantity, composition and qua-lity. The composition of orange juice depends on physiological conditions (related to climate, soil and fruit maturation), genetic characteristics of the oranges, and variations in processing and storage methods after harvest. Regarding intake recommendations, the scientists noted that excessive intake of any food, even for the healthiest, can lead to harmful effects.