Cranberries Versus Antibiotics in Preventing Infections

July 26, 2011— -- Cranberries have long been praised as a natural elixir to treat urinary tract infection symptoms, but a new study published in the Archives of Internal Medicine found that antibiotics may be better at preventing UTIs than those little red berries.

Researchers from the Academic Medical Center in Amsterdam gave low-dose antibiotics or cranberry capsules to 221 women who suffered from recurring urinary tract infections. After the year-long study period, researchers found that women who took the antibiotics suffered from fewer UTIs than those who took the cranberry extract.

But study authors noted that those who took the antibiotics also were more likely to build a resistance to the antibiotics, which could cause more infections in the future.

"Our experience from clinical practice is that women with recurrent UTIs do not like taking antibiotics for a long period because they know the resistance problem," said lead researcher, Marielle Beerepoot. "I think that doctors have to discuss the results of this study with the individual patients to make the best choice."

Women are more at risk of developing urinary tract infections than men, and more than half of all females will experience at least one UTI in their lifetime, according to the National Association for Continence. UTIs are caused by germs that enter the urethra and bladder, and E. coli is the most common of these bacteria.

Diabetes, kidney stones and pregnancy can put someone at higher risk of infection. Symptoms of an infection include cloudy or bloody urine, pain or burning during urination, pressure in the lower abdomen or back and strong urge to urinate often, even after just going to the bathroom.

The cranberry compound, known as A-type proanthocyanidins, fights infection by preventing bacteria from attaching to the walls of the urinary tract.

While Bill Gurley, professor of pharmaceutical sciences at University of Arkansas for Medical Sciences, was happy to see that the study opened up a foundation for more studies in the future, he said the 500 mg dose of cranberry extract in the study was too low to compete with the 480 mg twice-daily dose of antibiotics. Higher doses may have delivered different results.

And Beerepoot agreed.

"With a higher amount of working substance, it may be non-inferior to antibiotics," Beerepoot said. "A dose-finding study is still under way."

"Cranberry extract products have a low side effect profile," Gurly said. "What's neat is that there is usually a combination of unique compounds in botanicals. Once we get the dose right, cranberries could be a promising alternative in treating and preventing urinary tract infections."