When the burn starts, many women turn to this tart fruit juice for help.
Perhaps no home remedy is more associated with a urinary tract infection (UTI) than cranberry juice. Upon getting a UTI, many women will immediately stock up on cranberry products like cranberry juice or cranberry juice capsules in an attempt to “cure” their infection.
However, the relationship between cranberry juice and UTIs is not quite as strong as many women may believe. There is some truth behind this legend, but cranberry juice won’t actually “kill off” bacteria, and it probably won’t prevent UTIs for most women, either.
But it’s not exactly surprising that so many women turn to cranberry products when they start to feel the burn: UTIs are incredibly painful and unpleasant, and many people who get them are willing to try anything to soothe the pain.
UTIs are a burning, painful bacterial infection in the bladder. They occur when bacteria enter the urethra, where they can easily multiply and attach to the bladder wall, leading to an infection that causes painful UTI symptoms. More than half of women get at least one UTI in their lifetime, according to the U.S. Department on Health and Human Services.
The Truth About Cranberries + UTIs
Cranberries *do* influence the bacteria that cause UTIs (such as E. coli), but not in the way many people expect. Instead of fighting off any bacteria that enter the urethra or bladder, the components in cranberries help keep the bacteria from attaching to the surface of the urinary tract. If it can’t adhere, it can’t infect.
There’s just one problem with this cranberry superpower: It only seems to work in in vitro studies. In vitro literally translates to “in the glass,” and it refers to a study done in a tightly controlled lab environment, such as within a test tube or culture dish. That’s in contrast to an in vivo study, which translates to “in the living” and refers to a study done in more natural, realistic conditions.
In other words, the components of cranberries helped keep bacteria from attaching to surfaces of a culture dish, for example, but not necessarily the surfaces of the urinary tract. One reason for this might be that cranberry products have to go through the digestive process before they end up in the bladder, which may alter its specific effects on bacteria.
However, there might be one case in which cranberry products may help. In randomized, controlled trials, the only studies that were able to reveal benefits of cranberry products for UTIs were for women with recurrent UTIs. For those women, cranberry products did reduce the incidence of UTIs compared to a placebo.
But overall, the only proven, effective treatment for UTIs is antibiotics, which is why seeing your doctor when UTI symptoms start is important. As for keeping those UTIs away, instead of making cranberry juice part of your daily diet, here are effective tips to prevent a UTI.
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Hisano M, Bruschini H, Nicodemo AC, Srougi M. Cranberries and lower urinary tract infection prevention. Clinics (Sao Paulo). 2012 Jun;67(6):661-7.
Jepson RG, Craig JC. Cranberries for preventing urinary tract infections. Cochrane Database Syst Rev. 2008 Jan 23;(1).
Urinary tract infections. Bethesda, MD: Office on Women’s Health, U.S. Department on Health and Human Services. (Accessed on February 13, 2019 at https://www.womenshealth.gov/a-z-topics/urinary-tract-infections.)