Can Cranberry Juice Treat a UTI?

Over 150 million people will experience a urinary tract infection this year. Many of them will, upon diagnosis, race out to stock up on cranberry juice, a traditional ward against and treatment for UTI.

Cranberry juice, unfortunately, will not get the job done.

Cranberry capsules? Well, that's a different story!

First of all, what is a UTI, exactly? It describes any infection that occurs in any part of your urinary system – urethra, kidneys, ureter, and bladder. However, most involve the bladder and the urethra, and women are at a much greater risk than men. Symptoms can include frequent (and painful) urination, traces of blood in the urine, and pelvic pain. An infection in the upper urinary tract may precipitate pain in the flanks, nausea or fever as well as the “standard” symptoms.

Most of the time, UTIs can be treated with antibiotics. Although symptoms typically clear up after just a few days of treatment, patients will be encouraged to take the full course of treatment which will typically run from a week to ten days.

Now, here's the cranberry science: A UTI occurs when bacteria stick to the lining of your bladder. Cranberries produce A-type proanthocyandins, chemicals that interfere with the infecting bacteria's ability to adhere to the bladder wall. It has not been unreasonable, then, for doctors and grandmothers to proscribe cranberry juice as a UTI preventative and treatment.

But a team of researchers from the Texas A&M Health Science Center College of Medicine in Houston dug a little bit deeper and discovered that cranberry juice is not an effective protection against UTI. The researchers studied 160 patients undergoing elective gynecological surgery between 2011 and 2013. Normally 10 to 64% of women undergoing this treatment will develop a urinary tract infection upon the removal of the catheter placed during the surgical procedure.

What the researchers discovered was that it took the capsulized equivalent of 16 ounces of pure cranberry juice consumed daily to prevent bacterial adhesion. They concluded that cranberry juice, particularly the juice concentrates found at popular grocery stores, would not effectively treat a urinary tract infection.

But cranberry capsules lowered the risk of UTIs by 50%. Not only was the concentration of the active ingredient higher in the pills, but more of it reached the bladder. Most of the active ingredient in cranberry juice is long gone by the time the bladder is reached.

The research was just published in the American Journal of Obstetrics and Gynecology