For many years, cranberry juice or cranberry supplements have been promoted to prevent or treat urinary tract infections.  Some consider this a “home remedy” while others may cite research studies that show cranberry as an effective treatment.  Let’s explore cranberry juice, the facts and fiction.   

What is a urinary tract infection?

A urinary tract infection (UTI) occurs when bacteria in the kidney, ureter, bladder or urethra cause an infection.  This may cause symptoms such as pain, burning or difficulty urinating, frequent urination, an urgent need to go to the bathroom, blood in the urine, cloudy or foul-smelling urine, lower back pain, or fever.  A UTI is diagnosed by a urine test and typically treated using an antibiotic. The length of treatment can vary from three days to a longer course of medication, depending on the severity of the infection.

The facts about cranberries and UTIs

More than 20 national and international studies were examined, including randomized controlled research trials, considered the gold standard for evaluating effectiveness of a treatment.  These studies evaluated the role cranberries play in preventing or treating a urinary tract infection among a variety of populations, including children, adults, men, women, pregnant women, and those with certain medical conditions.

As of 2020, the current research shows cranberry products provide very little or no benefit in the prevention or treatment of a UTI when compared to a placebo.

How to prevent UTIs

Despite the lack of effectiveness of cranberries, there are things you can do to help prevent a urinary tract infection:

  • Drink water.  Hydrating with about two liters of water a day will help to flush the urinary tract, prevent infection and also is the most important way to prevent kidney stones.
  • Practice good hygiene.  Women should wipe front to back after urinating and a bowel movement.
  • Urinate after sex.  Urinating will help flush the lower part of the urinary tract.

Although cranberries are not effective in preventing or treating urinary tract infections, they are tasty, have antioxidant properties and are always a great compliment to holiday dinners!

If you are experiencing symptoms of a UTI, your primary care doctor can help.

 David W. Sobel, MD

David W. Sobel, MD

David Watson Sobel, MD, is a urologist at Rhode Island and The Miriam hospitals. He is also a clinical instructor (urology) at The Warren Alpert Medical School of Brown University. 

Dr. Sobel earned his undergraduate degree from Brown University, medical degree from Tufts University School of Medicine and completed his residency at University of Vermont Medical Center. He is a member of Rhode Island One Disaster Medical Assistance Team (RI-1 DMAT) and founder of the Consortium for Ureteral Stent Pain (CUSP) and the Pan-New England Stone Society (PNESS). Dr. Sobel is the recipient of the 2018 University of Vermont Laurence H. Coffin Research Award.