Cranberry Extract Keeps Urinary Tract Infections at Bay

Healthnotes Newswire (March 22, 2007)—What if you were told that you could cure your frequent urinary tract infections (UTIs) for good? According to a recent study in Phytomedicine, it might be as easy as taking a concentrated cranberry extract. Caused by an overgrowth of bacteria, UTIs are particularly common in women, infants, and the elderly. Symptoms can include a burning sensation with urination, a sense of urgency when having to void, frequent urination, bad-smelling urine, and dark, cloudy, or bloody urine.

Sexual intercourse, using estrogen (in oral contraceptives or hormone replacement therapy, for example), taking antibiotics, and being female all make it more likely that you’ll experience a UTI. Once you get one, you are more likely to suffer from another.

Antibiotics are usually prescribed to treat UTIs, but with repeated use the bacteria begin to “outsmart” the drugs—a process called bacterial resistance. To get around this, it’s important to prevent the infection before it begins.

Cranberries (Vaccinium macrocarpon) have been used historically to help prevent UTIs. Originally thought to work by acidifying the urine, it is now known that compounds called proanthocyanidins in the berries make it difficult for bacteria to stick to the walls of the bladder, potentially halting the infection.

Several studies have suggested that preparations made from dried cranberry juice or dried whole cranberries might help prevent UTIs. Researchers gave 12 women with a history of recurrent UTIs (six or more infections within a year) 400 mg of a concentrated cranberry extract (standardized to contain 30% phenolic compounds including at least 25% proanthocyanidins) each day for 12 weeks.

None of the women developed a UTI while taking the cranberry supplement, and they reported no adverse effects. What’s more, when they were interviewed two years later, the eight women who continued taking cranberry supplements were still UTI-free.

“The results of this study are unique in that none of the women in the study had a recurrent infection. Although this is just a pilot study and the results preliminary, it is a remarkable finding,” the team said.

The amount of phenolic compounds in the study supplement was much higher than that found in most cranberry preparations, which typically contain between 0.5 and 5% total phenolic compounds. “Comparison of this study with earlier reports suggests that there is a correlation between the amount of phenolic compounds ingested and the prevention of recurrent infections,” the researchers concluded.

Of note, one of the study’s authors is an employee of Phenolics, LLC, the company that manufactures the cranberry preparation used in the trial.

(Phytomedicine 2007;doi:10.1016/j.phymed.2007.01.004)

Kimberly Beauchamp, ND, earned her bachelor’s degree from the University of Rhode Island and her Doctorate of Naturopathic Medicine from Bastyr University in Kenmore, WA. She cofounded South County Naturopaths in Wakefield, RI. Dr. Beauchamp practices as a birth doula and lectures on topics including whole-foods nutrition, detoxification, and women’s health.

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