Cranberries help urinary tract infections, but not as juice
DASHING out for a bottle of cran berry juice when a urinary tract in fection hits may not be so helpful after all. Research published in the American Journal of Obstetrics and Gynecology suggests it could just be an old wives’ tale.
The active ingredients in cranberries prevent bacteria from adhering to the bladder wall. A urinary tract infection (UTI) can affect any part of the urinary system, kidneys, bladder or urethra.
More than 3 million Americans, mostly women, experience a UTI every year. Symptoms include frequent, painful urination, pelvic pain and traces blood in the urine. The infection does not normally last long, and most patients self-diagnose.
For many, the first port of call is a box of cranberry juice. However, new research suggests that while cranberry capsules can help, cranberry juice may be little more than a panacea. Dr. Timothy Boone, PhD, vice dean of the Texas A&M Health Science Center College of Medicine in Houston, and colleagues wanted to know if cranberries can really help. Cranberry capsules reduce the prevalence of UTI The team studied 160 patients aged 23-88 years who were undergoing elective gynecological surgery between 20112013. Normally, 10-64% of women undergoing this kind of surgery will develop a UTI following the removal of the catheter. Half of the patients received two cranberry juice capsules twice daily - the equivalent in strength to two 8-ounce servings of cranberry juice - for 6 weeks after surgery. The others took a placebo. Cranberry capsules lowered the risk of UTIs by 50%. In the cranberry treatment group, 19% of patients developed a UTI, compared with 38% of the placebo group.
So, how does it work? For a UTI to occur, bacteria must adhere to and invade the lining of the bladder. Cranberries contain A-type proanthocyanidins (PACs), which interfere with the bacteria’s ability to the bladder wall, reducing the likelihood of infection. However, the researchers point out that since a cranberry capsule provides the equivalent of 8 ounces of cranberry juice, a patient would need a lot of pure cranberry to prevent an infection.
Dr. Boone explains: “It takes an extremely large concentration of cranberry to prevent bacterial adhesion. This amount of concentration is not found in the juices we drink. There’s a possibility it was stronger back in our grandparents’ day, but definitely not in modern times.”
“Cranberry juice, especially the juice concentrates you find at the grocery store, will not treat a UTI or bladder infection. It can offer more hydration and possibly wash bacteria from your body more effectively, but the active ingredient in cranberry is long gone by the time it reaches your bladder.”