Can pure fruit and vegetable juices protect against cancer and cardiovascular disease too? A review of the evidence.

While it is widely accepted that fruit and vegetables (F&V) lower the risk of cancer, and cardiovascular disease (CVD), the role of pure fruit and vegetable (PFV) juices is often downplayed. This review poses two questions: Are the protective benefits of F&V dependent upon constituents lacking in PFV juices (e.g. fibre)? Do PFV juices impact on disease risk when considered separately from F&V? Studies comparing the effects of fibre and antioxidants were reviewed, yielding the finding that the impact of F&V may relate more strongly to antioxidants, than to fibre. For the second question, high-quality published studies that considered PFV juices were reviewed. The impact of PFV juices on cancer risk was weakly positive, although a lack of human data and contradictory findings hampered conclusions. For CVD, there was convincing evidence from epidemiological and clinical studies that PFV juices reduced risk via a number of probable mechanisms. It was concluded that the view that PFV juices are nutritionally inferior to F&V, in relation to chronic disease risk reduction, is unjustified.