Cranberry-containing products may be more than just a folk remedy for urinary tract infections (UTIs). A recent article from Archives of Internal Medicine concludes that cranberry-containing products offer women protection against UTIs, particularly those prone to recurrent infections.
Researchers studies over 1,600 men, women, and children of different populations including the elderly; the hospitalized; those with neuropathic bladder, spinal cord injuries, or multiple sclerosis; and pregnant women. Most of the trials (10) were conducted in North America; the remainder were conducted in Finland, Italy, and the United Kingdom.
Cranberry-containing products used in the studies took on different forms and dosages. Cranberry juice contains P a substance that has the ability to inhibit Escherichia coli from adhering to the lining of the bladder and the urethra, the tube that transports urine from the bladder to the outside of the body. The studies looked at cranberry juice as well as capsules or tablets.
The authors of the review concluded that cranberry-containing products are most protective against UTIs in women with recurrent infections. They also may offer protection to women in general, including those who are pregnant, and to children and other populations, but heterogeneity across the trials made interpretation difficult.
Interestingly, the studies showed that the cranberry juice was more effective than capsules or tablets, but the investigators noted that could be because women who drink cranberry juice are better hydrated. They also found that dosing at least twice daily seems necessary to achieve benefit.
Bottom Line: If you have recurrent urinary tract infections, daily cranberry juice may just be the tonic you need to decrease these infections.