A new US study shows cranberry juice anthocyanins have only limited absorption but the researchers note that, in spite of this low bioavailability, the levels may be sufficient to generate a sustained health beneficial effect in terms of cell metabolism and gene expression.

Cranberries contain a variety of anthocyanins, which are a sub-group of flavonoids, with reports in the literature suggesting flavonoids are powerful antioxidants, protecting the body from oxidative stress.