How much cranberry juice is enough to prevent urinary tract infections?

Date posted: 
Wednesday, April 27, 2016

Though cranberries have been used for many decades to prevent urinary tract infections, there has been no effort to determine an effective dose, primarily because there has been no research grade product available.

Data access has been approved for a randomized, placebo-controlled, dose-response study which aims to compare low dose and medium dose cranberry juice to a placebo in the prevention of recurrent urinary tract infections in adult women.

“Determining the effective dose range is desirable for several reasons,” says project lead, Dr Lynn Stothers, from the Department of Urologic Sciences at the University of British Columbia. “We need to ensure that the dose prescribed is effective. Compliance is likely to be higher if lower doses are required, and since the incidence of adverse effects will tend to increase with increasing doses, minimizing the dosage is desirable.”

“We hope to develop a dose curve relating the number of infections in each group compared to their intake of cranberry, and we hypothesize that the number of urinary tract infections will be significantly lower in subjects receiving cranberry juice compared with the group that receives the placebo.”

Dr Stothers also thinks it likely that there will be a decrease in outpatient physician visits and a decrease in prescription drugs costs for urinary tract infections in patients using cranberry juice, compared to those receiving the placebo.

Population Data BC will be linking BC Ministry of Health data with researcher collected data for the project, which is funded by the National Institutes of Health.

Page last revised: April 27, 2016