Last week, media outlets were quick to pick up the story of a research study that showed cranberry extract isn’t as effective as antibiotics for the prevention of recurrent urinary tract infections (UTIs). The headlines were consistent: “Antibiotics beat cranberries,” “Don’t bet on cranberry,” and “Cranberries little help”. Unfortunately, what is lacking from many of the medical news reports is a critical review of the study’s methodology and thus the validity and applicability of its results. While a study comparing the efficacy of antibiotics and cranberry is a great idea, the cranberry extract studied contained the daily equivalent of merely 9.1 mg of proanthocyanidins, the key chemical constituent responsible for protecting against adherence of bacteria in the urinary tract. This dose falls far short of the 72 mg daily dose of proanthocyanidins currently accepted as the most effective based on recent clinical studies, a problem admitted by the study’s authors in discussing their results.
Even at such a low dose, cranberry showed great promise.
After 12 months of taking either trimethoprim-sulfamethoxazole (TMP-SMX, 480 mg once daily) or cranberry capsules (500 mg, containing 4.55 mg of proanthocyanidins, twice daily):
- the mean number of women experiencing at least 1 UTI was greater in the cranberry than the antibiotic group (4.0 vs 1.8; p=0.02)
- the proportion with at least 1 UTI was also greater in the cranberry group (78.2% vs 71.1%; p=0.03)
- median time to first UTI was 4 months in the cranberry group, vs. 8 months in the antibiotic group
- 86.3% of fecal and 90.5% of asymptomatic bacteriuria E coli isolates were TMP-SMX resistant vs. 23.7% and 28.1% in the cranberry group
- increased resistance rates for was other types of antibiotics were also found in the TMP-SMX group after 1 month
- antibiotic resistance did not increase in the cranberry group
As noted by Galen’s Watch, “As part of a total treatment that included other supplements that have shown benefit in preventing UTI’s such as probiotics and vitamin C the outcome could be quite different. A typical treatment plan could include dietary recommendations and herbs, among other things.” All is not lost for cranberry. At the correct dose, it remains an important part of a holistic approach to preventing UTIs.
- Beerepoot MAJ et al. Cranberries vs antibiotics to prevent urinary tract infections. A randomized double-blind noninferiority trial in premenopausal women. Arch Intern Med [serial on the internet]. 2011 [cited 2011 July 30];171(14):1270-1278. Available from: http://archinte.ama-assn.org/cgi/content/short/171/14/1270.
- Freeman DW. For urinary tract infection, antibiotics beat cranberries. CBS News [website]. 2011 July 26 [cited 2011 July 30]. Available from: http://www.cbsnews.com/8301-504763_162-20083454-10391704.html.
- Gardner A. Don’t bet on cranberry against UTIs. CNN [website]. 2011 July 25 [cited 2011 July 30]. Available from: http://www.cnn.com/2011/HEALTH/07/25/antibiotics.cranberry.upi.prevention/.
- Walsh N. Cranberries little help for bladder. MedPageToday [website]. 2011 July 25 [cited 2011 July 30]. Available from: http://www.medpagetoday.com/InfectiousDisease/GeneralInfectiousDisease/27725.
- Howell AB et al. Dosage effect on uropathogenic Escherichia coli anti-adhesion activity in urine following consumption of cranberry powder standardized for proanthocyanidin content: a multicentric randomized double blind study. BMC Infect Dis [serial on the internet]. 2010 [cited 2011 July 30];10:94. Available from: http://www.biomedcentral.com/1471-2334/10/94#B12.
- Way S. Antibiotics beat Cranberries for UTI’s? Not so fast… Galen’s Watch . 2011 July 26 [cited 2011 July 30]. Available from: http://camwatcher.typepad.com/cam_watcher/2011/07/antibiotics-beat-cranberries-for-utis-that-is-what-the-headlines-say-but.html.
Imagine a therapy that is completely free, readily available, and virtually without side effects that can radically transform your health. It’s called “nature exposure,” or forest bathing. And it's easy as 1-2-3-4-5.
It’s official – fall is here and winter is coming. It’s rainy and grey outside today in Toronto and I just want to stay inside, wrap myself in layers of wool, and cozy up on the couch, preferably near a fireplace. Sometimes, that’s exactly what this naturopathic doctors orders, but every day, I’m still pushing myself to gear up and get outside. […]
I’ve never been good at mindful meditation. You know, the kind where you focus on your breath and develop awareness of your personal news ticker. The kind where you notice and name that voice inside your head that reviews your day, questions your every action, worries about everything, and can be your worst critic. And then you focus again on your breath. You’d think I’d be a pro. My mother was a yoga teacher in the 70s. She taught me breathing techniques and progressive muscle relaxation and visualization in my tweens. She introduced me to mindfulness and meditation and mindful meditation with the hopes that it would help lift me out of my depression. It didn’t. […]
I love simple ways that help calm anxiety and bring your attention to the present moment. Stop feelings of panic in their tracks with this exercise that makes use of your 5 senses to focus on the here and now. […]
It’s hard to describe what happens when panic sets in. People who don’t experience chronic acute anxiety episodes or PTSD (post-traumatic stress disorder) or dissociation often struggle to understand. As I woke the other day with a feeling of great distress, I found a new, truly geeky analogy to explain both the sensations and the management. […]
The idea of hearing voices is one of the most vilified aspects of mental illness. Hearing voices is frequently attributed to those living with schizophrenia and dissociative identity disorder, but is much more common, and complex, than its portrayal on TV or in media. Although auditory hallucinations can pose significant problems in some cases, voice-hearing can be positive and even, non-clinical. […]