Saturday, May 12, 2007

Wham: Cranberry for Urinary Tract Infections

An interesting small research study was done in the scientific journal Phytomed recently (2007;14:237-241), providing additional evidence that shows how Cranberry extract reduces urinary tract infections. Hopefully, these positive results will lead to more detailed larger studies. A full abstract of this trial, reported upon in HerbClip from American Botanical Council, is linked to today's headline. Quoting from Herbclip:

"Common in women, the elderly, and infants, urinary tract infections (UTIs) are defined as the "presence of a certain threshold number of bacteria in the urine (usually greater than 100,000 per mL)." One in four women who have a UTI will have a recurrence. Cranberry (Vaccinium macrocarpon) products are often used to prevent UTIs. The journal authors report on a study to test the effects of concentrated cranberry extract on women with recurrent UTIs.Most UTIs are caused by one type of bacterium -- Escherichia coli.

The authors conducted an open-label pilot study for 4 months at Helios Integrated Medicine, PC in Boulder, Colorado. Twelve women aged between 25 and 70 years with a history of 6 UTIs in the past year took 1 cranberry capsule twice daily for 12 weeks. Each capsule contained 200 mg cranberry extract standardized to 30% total phenols (much higher than dried cranberries and dried juices), produced by Phenolics, LLC (El Granada, CA), by selective extraction of the berries. The total cranberry proanthocyanidin intake during the study was approximately 100 mg per day. None of the women developed a UTI during the study, based on symptoms or laboratory results.

After 2 years, a follow-up was done, and the same medical history questionnaire was reviewed with each woman. At that time, eight of the women reported no changes in their health since the study began. They all continued to take various cranberry supplements prepared by different manufacturers in doses ranging from 150 to 300 mg per day, and they continued to be free from UTIs. Four women stopped taking cranberry supplements for various unrelated medical reasons. Of those, one remained free of UTIs and two developed symptoms, which resolved after resuming the supplementation. The fourth developed a UTI confirmed by urinalysis and was treated with antibiotics. She then resumed the cranberry supplements and did not have any further symptoms.

This study adds evidence to three previous studies cited by the authors that indicate the effectiveness of cranberry products in preventing UTIs in women. These study results are unique, however, in that none of the women had a recurrent infection during the study period. Also, this study used a unique cranberry product standardized to 30% phenolics."

As always, Sham vs. Wham would recommend that readers remember the tests done were of a specific brand of extract, and that if you want the same results, you buy the same brand as in the study.



curious said...

It's the D-Mannose in Cranberry that affects the e. coli bacteria so they won't stick to the bladder surface. you can get is without any Cranberry arround it at any healthfoodstore...

Dave Jensen said...

Thanks Curious! Good suggestion. I've always found herbalists of two minds on this. Some people say "go for the extracted biochemical with the effects" and others say "take the entire botanical product, as a food, and it will react better in your body." Good to know what the exact ingredient in the Cranberry is however!