# Medical use of cranberrry juice **URL:** \ **Category:** Factual Questions\ **Created:** [October 15, 2002, 6:21pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374 "2002-10-15T18:21:57Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![bensonGemini](https://avatars.discourse-cdn.com/v4/letter/b/eb9ed0/32.png) [@bensonGemini](https://boards.straightdope.com/u/bensonGemini)\ **Post date:** [October 15, 2002, 6:21pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/1 "2002-10-15T18:21:57Z")
I have heard that drinking a glass of cranberry juice a day can eliminate and prevent kidney stones. Is there any truth to that? And why? Also… I was looking at the bottle in the fridge, and it said ‘CALCIUM’ in big letters. Now correct me if I’m wrong, but isn’t calcium the very source of most kidney stones? Thanks. ---
**Author:** ![Earthworm\_Jim](https://avatars.discourse-cdn.com/v4/letter/e/f07891/32.png) [@Earthworm\_Jim](https://boards.straightdope.com/u/Earthworm_Jim)\ **Post date:** [October 15, 2002, 6:25pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/2 "2002-10-15T18:25:35Z")
> [@](#): > > \*Originally posted by bensonGemini \* > \*\*I have heard that drinking a glass of cranberry juice a day can eliminate and prevent kidney stones. Is there any truth to that? And why? Also… I was looking at the bottle in the fridge, and it said ‘CALCIUM’ in big letters. Now correct me if I’m wrong, but isn’t calcium the very source of most kidney stones? > > Thanks. \*\* I’m not sure about the kidney stone angle. However, I know that the doctor has told Missus Bubba to drink cranberry juice to ward off (or help fight) urinary tract infections. ---
**Author:** ![Ol\_Gaffer](https://avatars.discourse-cdn.com/v4/letter/o/8e8cbc/32.png) [@Ol\_Gaffer](https://boards.straightdope.com/u/Ol_Gaffer)\ **Post date:** [October 15, 2002, 6:49pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/3 "2002-10-15T18:49:34Z")
Mrs. Gaffer also enjoys a daily glass of cranberry juice as a UTI preventitive. She did have kidney stones a couple of years ago but they were due to pregnancy (mineral retention) and not due to diet. ---
**Author:** ![Ol\_Gaffer](https://avatars.discourse-cdn.com/v4/letter/o/8e8cbc/32.png) [@Ol\_Gaffer](https://boards.straightdope.com/u/Ol_Gaffer)\ **Post date:** [October 15, 2002, 7:00pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/4 "2002-10-15T19:00:03Z")
And, although cranberry juice may have some plumbing preventitive properties, I’m not sure how it could _eliminate_ kidney stones. If it did this, there would be millions of rejoicing individuals who were looking at the prospect of having to pass them! ---
**Author:** ![Scarlett67](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/scarlett67/32/7387_2.png) [@Scarlett67](https://boards.straightdope.com/u/Scarlett67)\ **Post date:** [October 15, 2002, 7:00pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/5 "2002-10-15T19:00:40Z")
Anecdotal evidence: I have a history of UTIs and kidney stones (3 so far; one was an oxalate stone). I haven’t had a recurrence (since 1996) since I started drinking cranberry juice on a somewhat daily basis. ---
**Author:** ![Revtim](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/revtim/32/1042_2.png) [@Revtim](https://boards.straightdope.com/u/Revtim)\ **Post date:** [October 15, 2002, 7:12pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/6 "2002-10-15T19:12:08Z")
I’m one of the few males that ever had a urinary tract infection (what’s next? a yeast infection?) and the doc told me to drink cranberry juice. I sure didn’t mind, I love the stuff. This was between 1981 and 1985. ---
**Author:** ![ZipperJJ](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zipperjj/32/211_2.png) [@ZipperJJ](https://boards.straightdope.com/u/ZipperJJ)\ **Post date:** [October 15, 2002, 7:26pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/7 "2002-10-15T19:26:13Z")
Does all cranberry juice have calcium? Lots of juices now are fortified with stuff not naturally found in them (I suspect for kids and adults who don’t like to drink milk), so maybe your bottle is just special, **benson** , and cranberry juice doesn’t really contain calcium. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [October 15, 2002, 9:55pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/8 "2002-10-15T21:55:59Z")
In order for cranberry juice to be effective against UTIs, you’d have to drink gallons and gallons of the stuff, which would probably lead to other complications; not that drinking it is bad for you, indeed fluid intake is generally good and cranberry juice has vitamins etc, but there’s no conclusive evidence that it is effective against UTIs (that’s what I keep hearing anyway). ---
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [October 15, 2002, 10:19pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/9 "2002-10-15T22:19:26Z")
AFAIK, cranberry juice contains a chemical which prevents the sticky outer coat of bacteria from adhering to the urinary tract ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [October 15, 2002, 10:20pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/10 "2002-10-15T22:20:09Z")
Fresh cranberries contain 7mg of calcium per 100g, which is rather low - strawberries contain twice as much, oranges contain 40mg (nearly six times the amount), spinach contains thirty times the amount ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [October 15, 2002, 10:26pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/11 "2002-10-15T22:26:15Z")
I believe that is true **Enola** , but the chemical is present in very very low concentration. ---
**Author:** ![Eva\_Luna](https://avatars.discourse-cdn.com/v4/letter/e/e495f1/32.png) [@Eva\_Luna](https://boards.straightdope.com/u/Eva_Luna)\ **Post date:** [October 15, 2002, 11:01pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/12 "2002-10-15T23:01:27Z")
Well, every time I’ve felt a UTI coming on, I’ve staved off the symptoms by chugging cranberry juice. (It’s always fun when the UTI starts on a Friday night, when you know the only way you’ll get to see a doctor before Monday is to go to the ER, which seems a bit extrme.) It works for me. Other liquids don’t. Heck, even my gyno recommended it. It’s never killed off the UTI entirely, but lessed the symptoms enough that I could function unitl I got to the doctor. ---
**Author:** ![Yeah](https://avatars.discourse-cdn.com/v4/letter/y/dbc845/32.png) [@Yeah](https://boards.straightdope.com/u/Yeah)\ **Post date:** [October 15, 2002, 11:18pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/13 "2002-10-15T23:18:17Z")
Time for the straight dope which, in medical matters, is usually the findings of a Cochrane Review. Below is the conclusion of Cochrane Database Syst Rev 2001;(3):CD001321, “Cranberries for preventing urinary tract infections” by Jepson RG, Mihaljevic L, Craig J. REVIEWER’S CONCLUSIONS: The small number of poor quality trials gives no reliable evidence of the effectiveness of cranberry juice and other cranberry products. The large number of dropouts/withdrawals from the trials indicates that cranberry juice may not be acceptable over long periods of time. There is no conclusive evidence to recommend cranberry juice for the prevention of UTIs. Further properly designed trials with relevant outcomes are needed. You can find the whole abstract at: > **[Cranberries for preventing urinary tract infections - PubMed](https://pubmed.ncbi.nlm.nih.gov/11686987/?dopt=Abstract)** > > The small number of poor quality trials gives no reliable evidence of the effectiveness of cranberry juice and other cranberry products. The large number of dropouts/withdrawals from the trials indicates that cranberry juice may not be acceptable... ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [October 15, 2002, 11:19pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/14 "2002-10-15T23:19:00Z")
Actually, it may be that the data I read is out of date; I’m now finding reports of recent clinical trials that appear to show positive results. ---
**Author:** ![Nightsong](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nightsong/32/3083_2.png) [@Nightsong](https://boards.straightdope.com/u/Nightsong)\ **Post date:** [October 15, 2002, 11:48pm UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/15 "2002-10-15T23:48:56Z")
Even if the chemcial compound in question isn’t in a high enough dosage to do much good unless you practically OD on cranberry juice, the fact that you’re pushing fluids helps. (Flush out those kidneys! Rinse out that bladder! Watch your water bill go sky high from flushing every 10 minutes!) 😃 And, to add to the anecdotal ‘evidence’: I, my sister, and my mother all can successfully fight off a UTI if we start chugging the 'juice at the first signs of a problem. But, if that’s the cranberry or the sudden fluid rush flushing out our systems… I can’t tell. End result is what matters to me though, in this case. 😉 * * * \<\< It’s not hard to meet expenses, they’re everywhere. \>\> ---
**Author:** ![Yeah](https://avatars.discourse-cdn.com/v4/letter/y/dbc845/32.png) [@Yeah](https://boards.straightdope.com/u/Yeah)\ **Post date:** [October 16, 2002, 1:47am UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/16 "2002-10-16T01:47:13Z")
"End result is what matters to me though, in this case. " Then you might try switching to water to save a few bucks. ---
**Author:** ![EasyPhil](https://avatars.discourse-cdn.com/v4/letter/e/e47c2d/32.png) [@EasyPhil](https://boards.straightdope.com/u/EasyPhil)\ **Post date:** [October 16, 2002, 3:11am UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/17 "2002-10-16T03:11:36Z")
There’s a difference between cranberry juice drinks and pure cranberry juice. Pure cranberry juice is awful tasting, but is probably what is used for UTI’s. Here’s a link: > **[LIVESTRONG.COM - Simple Healthy Living](https://www.livestrong.com/)** > > LIVESTRONG.COM offers diet, nutrition and fitness tips for a healthier lifestyle. Achieve your health goals with LIVESTRONG.COM's practical food and fitness tools, expert resources and an engaged community. ---
**Author:** ![Booker57](https://avatars.discourse-cdn.com/v4/letter/b/b9e5f3/32.png) [@Booker57](https://boards.straightdope.com/u/Booker57)\ **Post date:** [October 16, 2002, 3:21am UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/18 "2002-10-16T03:21:42Z")
> [@](#): > > \*Originally posted by EasyPhil \* > \*\*There’s a difference between cranberry juice drinks and pure cranberry juice. Pure cranberry juice is awful tasting, but is probably what is used for UTI’s. Here’s a link: > > [http://www.coolnurse.com/bladder.htm](http://www.coolnurse.com/bladder.htm) \*\* Cranberry juice drinks or blends? There is a difference. The highest consentration I can find is 27%. I love Cranberry juice. Straight or with vodka. Cold, very cold. ---
**Author:** ![EasyPhil](https://avatars.discourse-cdn.com/v4/letter/e/e47c2d/32.png) [@EasyPhil](https://boards.straightdope.com/u/EasyPhil)\ **Post date:** [October 16, 2002, 3:29am UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/19 "2002-10-16T03:29:42Z")
> [@](#): > > \*Originally posted by Booker57 \* > \*\* > > Cranberry juice drinks or blends? There is a difference. > > The highest consentration I can find is 27%. > I love Cranberry juice. Straight or with vodka. Cold, very cold. \*\* Go to a health food store and look in the juice department for the Lakewood brand, they have the 100% cranberry juice. ---
**Author:** ![flodnak](https://avatars.discourse-cdn.com/v4/letter/f/838e76/32.png) [@flodnak](https://boards.straightdope.com/u/flodnak)\ **Post date:** [October 16, 2002, 4:19am UTC](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374/20 "2002-10-16T04:19:20Z")
\ > [@](#): > > \*Originally posted by Revtim \* > \*\*I’m one of the few males that ever had a urinary tract infection (what’s next? a yeast infection?) \*\* Uh. You’ve heard of “jock itch”? (Not to mention things like thrush, a _Candida_ infection in the mouth, which can make your life miserable regardless of plumbing…) \ [Next page](https://boards.straightdope.com/t/medical-use-of-cranberrry-juice/132374.md?page=2)