Cranberry Juice Shows Promise in Combating Antibiotic Resistance in Bacteria That Cause UTIs 

Anyone who has suffered from a urinary tract infection (UTI) has likely heard the advice to drink more cranberry juice. Its impact on warding off UTIs is still disputed, but research has now determined that it may counter antibiotic resistance in bacteria that cause the infections.

A new study published in Applied and Environmental Microbiology has shown that cranberry juice can enhance the effectiveness of fosfomycin, an antibiotic commonly used as a UTI treatment. When researchers exposed strains of Escherichia coli (the main cause of UTIs) to cranberry juice, the majority of the strains absorbed more fosfomycin; this finding, the researchers believe, lays the groundwork for future testing to confirm what really happens in the body when those with UTIs drink cranberry juice.

Reinforcing UTI Antibiotics with Cranberry Juice

UTIs typically develop when bacteria like E. coli — which contributes to 85 percent of all cases — enter the urethra and spread through the urinary tract. UTIs often infect the bladder, leading to a condition known as cystitis; in rare instances, the kidneys can be infected, leading to a much more severe condition known as pyelonephritis.

According to the Centers for Disease Control and Prevention, symptoms of bladder infection include pain or burning while urinating, frequent urination, bloody urine, and pressure and cramping in the groin or lower abdomen; symptoms of kidney infection, on the other hand, include fever, chills, lower back pain, and nausea or vomiting.

Women are especially susceptible to getting UTIs, with more than half of all women likely to have an infection in their lifetime, according to a statement on the new study. This is due to a mix of anatomical reasons; women have a shorter urethra compared to men, and it’s more likely for bacteria to enter their urethra because of its proximity to the anal area.

UTIs are mostly treated with antibiotics, but there is concern over the rise of antibiotic resistance among bacteria. As a result, scientists are trying to find ways to improve the activity of antibiotics. One such solution may be cranberry juice.

In the new study, researchers tested 32 lab-grown strains of E. coli with cranberry juice, finding that in 72 percent of the E. coli strains tested, cranberry juice boosted the antibiotic activity of fosfomycin and suppressed the emergence of mutations associated with antibiotic resistance.

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Looking Into Natural Compounds

Although cranberry juice was shown to fight antimicrobial resistance in many of the E. coli strains, the researchers haven’t pinpointed the exact component in the juice that induces this effect. Something in the juice, they say, causes the bacteria to take in more sugars.

It just so happens that fosfomycin enters the bacteria through the same channels that sugars enter; this means that the E. coli strains exposed to cranberry juice are also coerced into absorbing more fosfomycin as well.

The researchers also aren’t sure if this same positive effect on antibiotic activity would occur after someone drinks cranberry juice, but future studies will aim to answer this question. In addition, the researchers hope to focus on the natural compounds in cranberry juice — these include proanthocyanidins and fructose, which have been found to deter bacteria from adhering to cells in the urothelium (the lining of the urinary tract).

The Impact of Cranberry Juice on UTIs

Antibiotics are still effective in treating UTIs by and large, but what help, if any, does cranberry juice provide? Cranberry juice won’t cure a UTI, but there is limited evidence that it may help reduce the risk of recurrent UTIs in healthy women, according to a 2020 FDA announcement.

Cranberry supplements in the form of pills may actually be a more effective option than juice, since cranberry juice is high in sugar, and it may not have the right active ingredient to act against UTIs, according to UTHealth Houston. Cranberry pills can be taken along with D-mannose, a simple sugar related to glucose that may reduce the number of certain bacteria that cause UTIs.

This article is not offering medical advice and should be used for informational purposes only.

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