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Hold the cranberries: UTI myths explained

Hold the cranberries: UTI myths explained

Source: Cleveland Clinic

The myths about preventing and treating a urinary tract infection (UTI) are many, but let’s get to the truth.

About 60 percent of women will experience this common malady (and the painful, frequent and sometimes urgent urination that goes with it) over their lifetimes. At the top of the UTI “myth list” is the widely held belief that drinking cranberry juice or taking cranberry supplements can prevent and treat UTIs.

“There is an active ingredient in cranberries that can prevent adherence of bacteria to the bladder wall, particularly E. coli,” says urologist Courtenay Moore, M.D. “But most of the studies have shown that juice and supplements don’t have enough of this active ingredient, A-type proanthocyanidins (PACs), to prevent bacteria from sticking to the urinary tract.”

Overall, clinical studies on the efficacy of cranberry juices and extracts for the prevention of UTIs are conflicting.

In 2012, the Cochrane Data Base identified 24 studies comparing cranberry products (juice or extracts) to control or alternative treatments. The review found that compared with placebo, cranberry products did not significantly reduce the occurrence of UTIs. The effectiveness of cranberry was not significantly different to antibiotics for women.

Also, because supplements are not regulated by the U.S. Food and Drug Administration, it’s not known how much of the active ingredient each product contains. Therefore, many of the products may not have enough of the active ingredient to be effective in preventing bacterial adherence to the bladder wall.


Dr. Moore says she’s heard all of the myths about how to prevent or treat UTIs — drinking lots of water, urinating after sex, avoiding tight-fitting pants and staying away from hot tubs, bubble baths and tampons. None of these beliefs is supported by any scientific data, she says.

On the other hand, here are three things that Dr. Moore says women should do to help prevent UTIs:

1. Take precautions to prevent UTIs after sexual activity.
“Frequency of sexual activity is strongly correlated with UTIs,” Moore says, and multiple partners and a history of sexually- transmitted diseases put you at the greatest risk. If you’re prone to recurrent UTIs, Dr. Moore advises against using spermicides or barrier contraceptives (like a diaphragm) and will often recommend a single dose of an oral antibiotic be taken before or after sex.

2. Develop good bowel habits.
Urinary tract infections are caused when bacteria from the rectum strays into the vagina, she says. That most commonly happens when you have constipation or diarrhea, so do what you can to stay regular.

3. Balance “good” bacteria with bad.
For women with recurrent UTIs, Dr. Moore often uses oral or vaginal probiotics, also known as “good” bacteria.

“You want more healthy bacteria so less bad bacteria can adhere to the vagina,” she says. Rushing to the grocery store for yogurt isn’t enough, though. “Not all yogurt brands have probiotics in them, and you’d have to eat about seven a day to get what you need,” she says.

(WhatDoctorsKnow is a magazine devoted to up-to-the minute information on health issues from physicians, major hospitals and clinics, universities and health care agencies across the U.S. Online at


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