Does Cranberry Really Work for Urinary Tract Infections?

cranberries and urinary tract infections

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Pretty much everyone knows that you should drink cranberry juice for a urinary tract infection. But is this an old wives tale?

The quick answer is no—it is not an old wives tale. The research on the benefits of cranberry juice has been around for a long time. And actually, it is one of the sugars, D-mannose, that is present in cranberry juice, that does all the work.

A clarification is important here. We are talking about REAL cranberry juice, not the cocktail junk loaded with added sugars. If anything, this type of drink will promote urinary tract infections. In addition to helping with urinary tract infections, cranberries are loaded with antioxidants. Which brings us to this particular study. In it, researchers looked at the effects of a single dose of either a placebo drink, a cranberry leaf extract beverage (CLEB) or low calorie cranberry juice cocktail (LCJC). All participants were given one of the drinks one week apart. Here’s what they found:

  • The cranberry drink increase blood glutathione peroxidase activity (a marker of antioxidant protection).
  • The cranberry cocktail increased glutathione concentrations and superoxide dismutase activity (antioxidant activity).
  • Interestingly, within the first 3 hours of drinking either cranberry beverage there was a strong ability to block the attachment of the bacteria E. coli to the wall of the bladder.

Personally, I was surprised that the cranberry juice cocktail had similar protection as the real stuff, but it is what it is. Either way, I would still steer patients towards the use of the real stuff.

In case you’re not aware of what constitutes the “real stuff,” look for the most expensive cranberry juice you can find. And it’s going to be very, very sour. More than what the average person would enjoy drinking. This is why it is typically mixed with other juices or with added sugars.

In addition to cranberry juice (or the straight up D-mannose, which can be bought separately from places like Amazon), I also recommend probiotic douches, to make sure that the normal, protective bacterial flora is present in the vaginal vault to keep future infections at bay.

James Bogash

For more than a decade, Dr. Bogash has stayed current with the medical literature as it relates to physiology, disease prevention and disease management. He uses his knowledge to educate patients, the community and cyberspace on the best way to avoid and / or manage chronic diseases using lifestyle and targeted supplementation.