Cranberry is natural herb ingredient of Cranalon™, FortiFi™
Cranberry is used both in folk medicine, as well as in cuisine for centuries. A study carried out in 2000 by Wang and Jiao revealed that cranberry juice is an effective scavenger of free radicals; therefore, the plant has antioxidant properties. Cranberry is also rich in flavonoids, citric and other acids and vitamin C. Clinical trials showed that cranberry helps prevent urinary tract infections. (1,2)
Health benefits and potential health benefits
Cranberries are a source of polyphenol antioxidants, phytochemicals under active research for possible benefits to the cardiovascular system, immune system and as anti-cancer agents.
Cranberry juice contains a chemical component, a high molecular weight non-dializable material (NDM), as noted above, that is able to inhibit and even reverse the formation of plaque by Streptococcus mutains pathogens that cause tooth decay. Cranberry juice components also show efficacy against formation of kidney stones.
Raw cranberries and cranberry juice are abundant food sources of the anthocyanidin flavonoids, cyanidin, peonidin and quercetin. These compounds have an unknown effect on human health, but are powerful against human cancer cells in vitro. Their effect in humans, however, is unproven, showing poor absorption into human cells and rapid elimination from blood.
Since 2002, there has been an increasing focus on the potential role of cranberry polyphenolic constituents in preventing several types of cancer. In a 2001 University of Maine study that compared cranberries with twenty other fruits, cranberries had the largest amount of both free and total phenols, with red grapes at a distant second place. Cranberry tannins have anti-clotting properties and may reduce urinary tract infections and the amount of dental plaque-causing oral bacteria, thus being a prophylaxis for gingivitis.
There is potential benefit of cranberry juice consumption against bacterial infections in the urinary system. Research shows that an effect occurs from a component of the juice inhibiting bacterial attachment to the bladder and urethra.
Although promising for anti-bacterial activity, long-term consumption of cranberry juice has only limited evidence for beneficial effects against urinary tract infections in women. Similar applications have not been successfully proved in other clinical trials of consuming cranberry juice or tablets by people with spinal cord injury associated with bladder catheterization, neurogenic bladder or infrequent urination, any of which may be associated with increased susceptibility to bacterial infections.
Current and completed clinical trials
In April 2004, the French government agency AFSSA, which regulates food products in a way similar to the United States Food and Drug Administration, granted approval of cranberry juice as an antibacterial agent for urinary tract health.
To date, four completed randomized clinical trials have shown evidence for inhibiting bacterial infections in the urinary tract of women by drinking cranberry juice over a 12 month period.
The US National Center for Complementary and Alternative Medicine (NCCAM) also reports three recently completed and four ongoing clinical trials of cranberry juice or capsules (pharmacy). Six of these human studies are examining antibacterial effects in female urinary tract infections. One evaluates effects of cranberry polyphenols on cytochrom P450 enzymes involved in metabolism. To evaluate the drug interaction potential of cranberry, alprazolam, dextromethorphan and caffeine are being examined. As of January 2008, the results of these trials have not been published.
An autumn 2004 caution from the Committee on Safety of Medicines, the UK agency dealing with drug safety, advised patients taking warfarin not to drink cranberry juice after adverse effects (such as increased incidence of bruising) were reported, possibly resulting from the presence of salicylic acid native to polyphenol-rich plants such as the cranberry. However, during 2006-8, several reviews of case reports and pilot studies have failed to confirm this effect, collectively indicating no statistically significant interaction between daily consumption of 250 mL cranberry juice and warfarin in the general population (3).
1. Walker EB, Barney DP, Mickelsen JN, et al. Cranberry concentrate: UTI prophylaxis. J Family Pract 1997;45:167-8 [letter].
2. Avorn J, Monane M, Gurwitz JH, et al. Reduction of bacteriuria and pyruria after ingestion of cranberry juice. JAMA 1994;271:751-4.