Evidence from a new placebo-controlled study published this month in Clinical Infectious Diseases may dispel the popular notion that cranberry juice is an effective preventive against recurrent bladder infections. Researchers recruited 319 women who had just recovered from a bladder infection and assigned half to drink 16 ounces of low-calorie cranberry juice cocktail daily for six months. The remaining participants in the placebo group drank a special juice developed by Ocean Spray that looked and tasted like real cranberry juice but had no actual cranberry content. Analysis of the results found that the difference in the rate of bladder infection re-occurrence was not statistically significant between the two groups, and therefore, cranberry juice apparently offers no protection against future bladder infection.
“This is yet one more example of a study that runs counter to popular wisdom,” says ACSH’s Dr. Elizabeth Whelan. “We now see that the beneficial health effects derived from cranberries may only be minimal at best, at least in reducing bladder infections, although a larger study should be completed.”