D-mannose for UTI made it into our list of the ten most searched UTI home remedies, among other UTI home remedies like vitamin C, probiotics and Pau d’arco. We also get a lot of questions about it. It’s clearly popular, but does D-mannose work for recurrent UTI?
Jump To Section:
- What is D-mannose? >>>>
- The science behind D-mannose. >>>>
- Where does D-mannose come from? >>>>
- The problems with D-mannose for UTI. >>>>
- What the D-mannose research tells us. >>>>
D-Mannose In Brief
Some studies suggest that D-mannose may be effective prophylactically for some cases and help to prevent urinary tract infections. Other studies show that D-mannose primarily reduces the severity of symptoms.
Yet another study concluded that D-mannose may be effective in treating an acute UTI.
So what does all this mean? In a nutshell, there is not yet enough research to tweeze out exactly what to use D-mannose for, what pathogens it may be protective against in vivo (in actual patients and not just in a lab setting), and what the correct dosage should be.
It’s also important to know that D-mannose for UTI is not FDA regulated.
But it’s firmly on our radar – so read on to find out what we do know so far.
What Is D-Mannose?
D-mannose is a simple sugar (monosaccharide) that is closely related to the glucose found in many fruits, vegetables, and plants. It also occurs naturally in some cells in the human body.
D-mannose is rapidly absorbed and reaches organs within 30 minutes, after which it may be excreted via the urinary tract. The human body can’t metabolize or store D-mannose, though it is possible much of it is metabolized by bacteria in the gut.
Any effect on blood sugar levels should be minimal. For this reason, many sources claim D-mannose is safe for use by diabetics. Others issue a caution, so it’s always best to discuss its use with your doctor.
What Do We Know About D-Mannose For UTI?
Here’s the short answer: We don’t know enough about D-mannose for UTI. As mentioned above, there is a clear lack of studies into whether D-mannose for UTI is beneficial.
Studies that do exist have not tested appropriate dosage, and limited studies exist for the effectiveness of D-mannose for females who experience recurrent UTIs.
Most look at D-mannose against a microorganism in vitro, that is, on the lab bench, and not in females with symptoms, so we don’t have a lot of information about D-mannose out in the real world (in vivo).
The largest and most heavily referenced study in humans we have found involved 308 women.
In this study, the prophylactic use of D-mannose significantly reduced the risk of recurrent UTI, and was shown to be as effective as nitrofurantoin, an antibiotic.
Other Applications For D-Mannose
Other uses of D-mannose include reversing the effects of metabolic syndrome and support for intestinal problems.
Infants and children who have a rare inherited disorder called carbohydrate-deficient glycoprotein syndrome type 1b take D-mannose.
People with this condition have a deficiency of a specific protein in their intestines, the symptoms of which are reversible with dietary supplementation of D-mannose. In these cases, D-mannose improves liver function, lowers blood sugar levels, and helps prevent blood clotting disorders.
Some studies show that D-mannose may act as a prebiotic and may therefore help regulate the gut microbiome.
A prebiotic is a food substance that is non-digestible to humans, but provides a food source for “good” bacteria in your digestive system.
The Science Behind D-Mannose For UTI
It has been suggested in vitro (on a lab bench), that D-mannose competes with the uroepithelial cells (the bladder lining cells), for the “attention” of the finger-like projections, or pili, of bacteria. See the comparison below, showing the pili of E. coli vs. the smoother surface of Lactobacillus.
If the bacteria does not stick to the bladder lining, they cannot colonize the bladder and cause an infection.
Let’s dig a little deeper into this. Certain types of E. coli bacteria are known to bind to the mannosylated glycoprotein uroplakin Ia that is present in the bladder lining cells. D-mannose molecules, if present in the bladder, may provide an alternative for E. coli to bind to.
According to the theory, when E. coli bind with D-mannose molecules, the combined particles are flushed from the bladder during urination. Thus, the E. coli are prevented from adhering to the bladder wall and causing a urinary tract infection.
D-Mannose Eliminates Bacteria Without Killing Them
In vitro (outside the body) E. coli has been shown to opportunistically bind to free-floating D-mannose. When ingested, it’s theorized that D-mannose may make it as far as the bladder. If this is true, E. coli may bind to D-mannose floating in the bladder, instead of the molecules in the bladder wall.
If the above process occurs in the bladder, any E. coli that have bound to D-mannose molecules would be eliminated from the body in the urine, before they are able to colonize.
While all this sounds promising, it’s important to reiterate that this has only been tested in a laboratory setting, and it has not been proven to actually happen in the body.
Where Does D-Mannose Come From?
As stated earlier, D-mannose is primarily derived from plants and fruits. Interestingly, D-mannose can also be found in sources like spent coffee-grounds, in which it can make up around 21% of its dry weight.
But of course we cannot eat spent coffee grounds to get an active dose of D-mannose in our bodies because we cannot effectively digest the coffee grounds to extract the D-mannose.
This would also mean ingesting other chemical products that would be more harmful to us than the protective effect of D-mannose.
In addition, eating coffee grounds is linked to an increase in blood cholesterol by an average of 26 points after three weeks. This is attributed to the consumption of the cafestol and kahweol that is found in spent coffee grounds.
Can I Eat Enough Cranberries To Get An Active Dosage Of D-Mannose?
Another source of D-mannose is cranberries. However, D-mannose makes up just 0.04% of the dry weight of cranberries. This is quite low in comparison to other sources, even the spent coffee grounds.
Needless to say, you would need to eat a ton of cranberries for your body to gain anything close to a protective dose of D-mannose. So this is not recommended as a method of ingesting D-mannose.
Watch our expert video series to learn more about D-mannose for UTI.
How Is D-Mannose Made?
There are a few ways the D-mannose you’ll find in a store could have been made.
Chemical Extraction Of D-Mannose
Currently, most of the D-mannose products in the food market are extracted from plants in chemical processing plants by either isomerization, hydrolysis, or catalyst reactions.
All this means is that other chemicals (such as 1% ammonium orthomolybdate or water) are added to turn D-glucose, D-sucrose, or D-mannitol into D-mannose.
The process flips the arrangement of chemical groups, adds a chemical group, and/or converts chemical groups so the original substance turns into D-mannose.
This is done under the perfect temperatures and acidity to have maximum product yield. D-mannose is then purified before being packaged and sold.
These processes are not ideal in terms of chemical purity. And because D-mannose is used as a dietary supplement and for medicinal reasons, it should not have any chemical contamination.
For this reason, the methods of chemical extraction and other chemical-based production methods are becoming less desirable. Instead, biological production methods for D-mannose are now being favored.
Biological Production Of D-Mannose
Biological production of D-mannose involves using readily available sugars such as D-fructose or D-glucose and enzymatically converting it into D-mannose.
An enzyme is a biological catalyst (increases the rate of chemical reaction) that does not break down or get consumed in the reaction.
Enzymes (such as D‐mannose isomerase) used to convert D-fructose or D-glucose into D-mannose are sourced from various organisms. Fun fact: some of these enzymes are actually sourced from bacteria such as E. Coli!
The Problems With D-Mannose For UTI
As we previously mentioned, D-mannose is not an FDA approved or regulated substance. This means that D-mannose can be manufactured in different countries, imported into the U.S. and sold on Amazon or via health food stores.
Many brands do not disclose the original source of the D-mannose in their products.
The problem here is that as a consumer, this makes it very difficult to know whether a particular D-mannose product is high quality, and whether it contains other chemicals that are not listed on the label.
If you are going to purchase D-mannose, make sure it is from a trusted company with reliable reviews. It also helps if the brand provides transparency as to where and how the D-mannose is sourced, and a certificate of analysis, showing what the product contains.
There has been no study reporting the toxicity of D-mannose in humans. However, it may be worth mentioning that D-mannose is toxic to honeybees when given as a sole source of food and it can blind genetically modified mice. What the implications of this may be for humans (if any), is not known.
In addition, a recent study has shown D-mannose to have no significant effect on women with recurrent UTI in primary care, compared to a placebo. However, it’s important to recognize the study’s limitations, including the lack of bacterial identification, and the absence of adherence tracking. Most importantly, if D-mannose works for you, there is no documented reason to discontinue using it.
A Cochrane review in 2022 revealed that the quality of evidence surrounding D-mannose as a prevention and treatment method for UTI is poor. This highlights the need for substantial research into the supplement, and to help understand possible interactions with other remedies and medications.
What Are The Possible Side Effects Of Using D-Mannose?
D-mannose is generally well tolerated by children and adults. However, there have been no studies done to confirm whether D-mannose is safe during pregnancy or breastfeeding.
Manufacturers of D-mannose state that possible side effects include bloating and loose stools.
In addition to the lack of general knowledge about D-mannose on its own, how D-mannose may interact with other medications and supplements is not well studied. It’s always best to talk to your doctor if you are concerned.
Can D-Mannose Interact With Other Home Remedies?
There may be interactions between D-mannose and other home remedy supplements taken, including UTI home remedies.
There is not yet enough research out there to see exactly whether these interactions may be beneficial or harmful, but there are indications it can happen.
For example, in one study that looked at the effectiveness of plant extracts plus D-mannose in preventing the recurrence of UTIs, three different combinations were given to patients.
These combinations all contained D-mannose, with the following plant extract groups:
A: Berberine, arbutin and birch
B: Berberine, arbutin, birch and forskolin
C: Proanthocyanidins
At the end of the treatment, the recurrence of cystitis was assessed. It was determined that patients in groups A and B had a lower incidence of episodes of recurrent cystitis during treatment and follow-up, compared to patients in group C.
Groups A and B also had urine samples with a significantly lower median bacterial load compared to patients in group C.
What The D-Mannose Research Tells Us
D-mannose studies:
- D-mannose: a promising support for acute urinary tract infections in women. A pilot study.
- Intervening with urinary tract infections using anti-adhesives based on the crystal structure of the FimH-oligomannose-3 complex.
- D-mannose powder for prophylaxis of recurrent urinary tract infections in women: a randomized clinical trial.
- Oral D-mannose in recurrent urinary tract infections in women: a pilot study.
- D-mannose: Properties, Production, and Applications: An Overview.
- The use of chemotherapeutic agents as prophylaxis for recurrent urinary tract infection in healthy nonpregnant women: A network meta-analysis.
- In vitro efficacy of phytotherapeutics suggested for prevention and therapy of urinary tract infections.
What was tested:
- How D-mannose works when used to treat urinary tract infections.
- Whether D-mannose is effective in treating acute UTI in females.
- Whether D-mannose is effective for recurrent UTI.
What was found:
- Use of D-mannose resulted in a significant improvement in the majority of symptoms of an acute UTI.
- D-mannose showed promise as a long term prophylactic (preventative) treatment for recurrent UTI.
- It appears that D-mannose may work by preventing E. coli from binding with the bladder lining.
- D-mannose appears to be a safe treatment.
- Fosfomycin ranks better in terms of efficacy, but it has more adverse side-effects than D-mannose.
- Further studies are essential to confirm the results found in these studies.
What you need to know:
- The mechanism of D-mannose has been proven in vitro only (outside of a living organism).
- So far, D-mannose blocked adhesive properties of E.Coli, Klebsiella, Serratia, and Enterobacter. But does not affect the bacterial growth. This was done in vitro only.
- Prophylactic treatment for recurrent UTIs has been shown to be a temporary measure in many cases, with infections returning at the same rate once treatment is stopped.
- No studies exist that specifically test the use of D-mannose for chronic urinary tract infections caused by bacterial biofilms.
Summary:
- D-mannose may be effective as a treatment for an acute UTI caused by E.coli.
- D-mannose may effectively relieve acute UTI symptoms caused by type 1 fimbriae-positive bacteria.
- Further research is needed to confirm whether D-mannose is effective as a treatment for recurrent UTIs, or whether it is useful for managing symptoms only.
- Studies are required into whether D-mannose is useful for bacterial biofilm infections of the bladder.
CONCLUSION: D-mannose shows promise for treatment of acute UTI caused by E. coli, but requires further study for effectiveness on recurrent or chronic UTI.
How Much D-Mannose Should You Take For UTI?
Most studies base the dosage of D-mannose on the recommendations of manufacturers. These range from 2 grams of D-mannose diluted in 200 mL of water once daily to twice daily if the symptoms are severe.
Unfortunately there is no FDA regulation regarding how much D-mannose should be taken or what the correct dosage for D-mannose should be.
In addition to this, there are no long-term studies determining whether there are any negative effects of taking D-mannose for an extended period of time.
The Financial Burden Of D-Mannose For UTI
Recurrent UTIs are expensive. The financial burden of treating recurrent UTIs with prophylactic D-mannose is estimated at $50 per year. However, anecdotally it would appear that recurrent UTI sufferers that rely on D-mannose spend far more than this.
This all adds up to quite a bit for something that has no definitive evidence around whether it works or not.
This estimate also does not take into account any antibiotics, the cost of visiting a doctor, or any other alternative remedy that might be used.
Our (Not So) Final Word On D-Mannose For UTI
Many people who suffer from UTIs swear by D-mannose for UTI. You’ll often see D-mannose recommended in forums and natural remedy articles.
The best way to establish the effectiveness of D-mannose is multiple large-scale, randomized, placebo-controlled, double-blind clinical trials.
These will help us understand the potential prophylactic properties of D-mannose, D-mannose as a treatment option for acute UTIs, and just whether D-mannose works as a natural way to relieve UTI symptoms.
Despite there being more recent studies, most of the information you see online about D-mannose for UTI comes from a single study conducted in 2013. Even the researchers in this study concluded that more clinical trials must be done on D-mannose to understand its effectiveness.
We are currently a long way short of the standard of evidence we need to safely take so many herbal remedies. Hopefully, this will change, as more and more people are looking towards home remedies for solutions and as an alternative to antibiotics.
To get answers to commonly asked questions about chronic and recurrent UTI, visit our FAQ page. Share your questions and comments below, or get in touch with our team.
If you are interested in learning more about practitioner vetted D-mannose products, please provide your name and email address in the green box below.
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Comments
Hello, could you please share brand recommendations for d-mannose? I’d like to try it but am unsure of where to buy / what brands are good. Thank you!
Hi Rachael, we shared more information by email. I hope it helps! Melissa
Please send me a list of the best D-Mannose products to try for helping to prevent recurrent UTIs. Thank you.
Hi Julie, we sent the information by email. You’re welcome to ask any further questions there. Melissa
I would appreciate the info on best D-Mannose products to try. Thank you.
Hi Betsy, we sent an email with more information. I hope it helps, Melissa
After reading your article on D-Mannose, and from my own reading on the stuff when I was suffering from a UTI eight years ago…WHY is the research on this so pathetic? SO many women swear by it, as I have read, you have said, and I have experienced. Just plain bizarre. Once again, women’s health marginalised.
Hi Annabel, we come across this lack of research in women’s health in every aspect of our work and are hoping to change that. Thanks for joining the conversation, Molly.
Hello, can you please share the trustworthy d-mannose brands with me as well? Thank you
Hi Georgena, we sent you some links by email. I hope it helps, Melissa
My 9 year old daughter is getting reoccurring UTI. Bloods confirmed She’s low in iron. Is this linked?
Hi Ashling, low iron could be linked to many things. As we’re not clinicians we can’t provide specific recommendations. We may be able to share information about UTI specialists who work with children, depending where you are based. If you’re interested in that information, please send us a direct message. Melissa
Hello. I tried D-mannose yesterday and I’m feeling the side effects of cramping and diarrhea. I use the Now! brand and the dosage states to take 2g (or 1tsp) but the conversion seems wrong as 1 tsp converts to 4.2g. In my case i took 1 tsp (used an actual tsp) and mixed it with 2 cups of water. I’m still feeling the side effects and now im thinking i might have overdosed myself😭 do you know how long the side effects should last? as for next time, I will try to lower the dosage to 500mg a day instead (once the side effects subside of course).
Hi Kimberley, there isn’t a lot of information about possible side effects of d-mannose, though bloating and loose stools are listed as a possibility by manufacturers. At the moment we don’t have any information about how long such side effects might last. Melissa
Trying it now
Hi Evon, I hope you find it helpful! Melissa
I’ve battled with years of UTI bouts after intimacy and looking for assistance in finding the best natural enzymatically converted D-mannose for my proactive regime. I have had much difficulty finding a trusted manufacturer. I take no other supplements regularly. Can you please help direct me or provide certain search criteria? I find studies often and they are fascinating but they don’t help solve my challenge. TYSM 🙂
Thank
Hi CLA, I’ve sent you an email with some information. Please let me know if you have any questions. Melissa
Hi please can you let me have the names of pure d mannose i live in uk. Thankyou
Hi Maureen, we sent you an email earlier with some information about one brand that our community reports positively about. Melissa
Is there cranberry in this as I’m on blood thinners.
Hi there, D-mannose is not typically derived from cranberry, however, some D-mannose products have added cranberry extract, so it’s important to read the ingredients on any product you are considering. Melissa
Does mannose make the urine more acidic or alkaline?
Hi Richard, this is a good question and one that we have not yet found any research to conclusively answer. Sorry we can’t be of more help at this stage. Melissa
I had a UTI 2 months ago that came back 2 weeks later. Got a round of cipro and 4 days later the burning came back! I immediately started taking DMannose and within 30-60 min the pain greatly subsided or went away. So I’ve been taking that 3 times a day for the past two weeks. My bladder feels inflammed. No pain while urinating, mostly burning of my urethra or bladder between urinating. Worried my doctor will just give more antibiotics (I got strips and no bacteria coming up). How do I heal my bladder/lining. The dmannose is my god send, and now drinking marshmallow tea. Alcohol definitely flares it up so wonder if it’s more like IC. But since it’s early I’m hoping to heal it. Any help or thoughts would be appreciated. Oh and taking PACs too. But I only notice relief with dmannose.
Hi Tara, can you send me a direct message and let me know where you’re based so I can share the resources that are most relevant? Thanks, Melissa
Hello, can you please share the trustworthy d-mannose brands with me please, as well?
Hi Raluca, I just sent you an email with more information. I hope it helps. Melissa
Hi I am 55 and recently cannot shake off this uti. I have had several antibiotics recently but uti comes back. I am not sure if I can take dmannose with antibiotics? I am at my wots end and fed up. Dmannose seems to lessen the symptoms but so far has not cleared it yet i see people saying it has transformed their lives.
Hi Eleanor, I saw you also sent us an email so I’ve just responded there. Melissa
5 years ago I was having re-occurring UTI’s. After many tests, the conclusion of my Urologist was that I learn to insert a catheter after each urination to get the small amount of urine left. I was 66 at that time. I struggled with this – so hard!! I remembered that a friend had told me about D-Mannose. I started taking 1/2 the dosage (1-500mg) daily. I have NOT had one UTI since!! Also, I found a new Urologist! I tell every doctor about this. The only Doc that I had positive comments about it was a veterinarian. My son gives it to his husky who has UTI problems!
Hi Emma, I’m so glad to hear it has been working for you! Melissa
Thanks for the insight
Hi I went to an MD and was prescribed an antibiotic twice a day for five days. I then began taking the D-Mannose to try to make sure I am clear of the UTI. So far I feel better though not 100%. I have also been drinking a lot of water instead of so many sodas. I just want to thank you for this article it is honest and informative. Please keep me updated via email on this article and anything else which may be of interest. Thanks Devon
Hi Devon, thanks for your positive feedback. I’m glad to hear you’re feeling better and I hope your symptoms fully resolve. If you’d like to be kept updated, you are welcome to join our mailing list. Melissa
Your contact form is not working, it gives me an error message. Could this me fixed please?
Hi Katrine, thanks for letting me know. I’m looking into it and hope it will be fixed soon. Melissa
Please let me know which high dosage dmannose brands are best. Thanks!
Hi Ashley, I replied with more information to one of your previous emails. Melissa
Please let me know which brand or manufacturer of D Mannose you recommend. I try to take supplements that are free of corn, dairy, gluten, soy, and rice derivatives and fillers whenever possible.
Hi Natashia, I saw you also sent us an email so I’ve replied there with more information. Melissa
Hello – i too am interested in learning more about supplement that would be is well received by your standards and knowledge on this topic.
Hi Ana-Maria, I just sent you an email with more information. Melissa
Would you provide me with suggested manufacturer & dosage. Thanks
Hi Marge, dosage very much depends on the individual and it’s always best to speak with a doctor. If you’re not sure where to find one, let us know where you’re based, and we may be able to help. I’ve also sent you an email with some more info. Susy
Hi, I’ve just started having sex with a new partner and now get a UTI everytime which is really having an impact on my life. I used to have this issue a few years ago but never had a problem with my previous partner. I have tried all the usual preventative measures but nothing has worked so I would like to give D mannose a try. I have read many different articles and websites which all vary in how much you should take. Please could you advise how many grams I should be taking a day as a preventative measure and for how long I need to take it before it might stop be getting UTIs after sex? Thanks so much!
I got since May a UTI what have not go away. Was described Cipro first for 10 days. Side effects was terrible. Was hurting all over, still my bones hurt. Doesn’t have take care of the UTI. Than 7 days of Bactrim, doesn’t helped easier. I was sick all over from the antibiotics and from the UTI, what I got now for 5 month. I read about D-mannose, ordered it and started today. I am using the powder. Took one in the morning, one after dinner, now is 11 pm and I am pain free after 5 month. Will continue taking it twice for 3 or 4 days, than once a day. When your UTI doesn’t go away this makes your whole body sick. I am in heaven today, thanks God I ordered it
Hi Gaby, so glad to hear it is working for you. I hope your symptoms are completely resolved. Melissa
Hi Cara, sorry to hear you’re experiencing this. Many people start with the dosages recommended on the product (which are based on the available studies), then vary their dosages, according to their symptoms. However, it’s always best to speak with a practitioner about this. If you are looking for a practitioner, we have some names that we can share via email, just let me know. Susy
Dear Amy,
I had a urine sample sent to the lab and it came back positive for Staphylococcus Satryophyticus. Do you know if D-mannose would be beneficial for treating this bacteria (I am taking antibiotics too). Also, if it would be helpful in future prevention of thisbcertqin strain of bacteria.
Thanks so much for your website, it’s brilliant 😊
Hi Jennifer, according to the studies mentioned above, D-mannose has shown promise for prevention of UTI caused by E. coli and possibly other gram negative organisms, but the evidence is limited so far. Staphylococcus saprophyticus is gram positive, so at this point there is no evidence that D-mannose may help. More research is needed. Melissa
I just ordered D-mannose. I figure to double up for a couple of weeks or until symptoms go away. If it seems to be effective, then I’ll continue with a single 1500mg tab/day. I also ordered Biofilm Defense. Should I have any problems taking these two together? I’ve given up on antibiotics.
Hi Marva, it’s best to speak with a practitioner about possible interactions between supplements. We can’t provide this type of insight. Melissa
Thanks, Melissa. I’ll be doing more research, of course. Where I live is practically Grand Central Station of natural treatments. From what I’ve been reading, I don’t see any particular danger in combining the Biofilm Defense and the D-Mannose, but I was hoping you all would know off the top of your heads. Thanks.
I have 3rd stage kidney disease. Is it safe to take dmanoose
Hi Nancy, we haven’t come across any resources that confirm the safety of D-mannose in this scenario – it’s best to speak with a doctor. If you’re not sure where to find one that can help, you can send us a direct message. Please include information on where you are based. Melissa
Can you please also email me a list of the best brands of d-mannose?? And do you happen to know what would be the dosage for a 3 year old to take prophylacticly? She’s been on prophylactic antibiotics for 2 years (she was diagnosed with VUR) and I’m looking for ways to manage it naturally as her reflux is starting to improve. Thank you!
Hi Lindsay, I just sent you an email with a link. I hope it helps, Melissa
Hi there, I’m UK based and was wondering if you knew the best brand for D Mannose powder that’s pure and hasn’t got any added fillers? Thank you!
Hi Sophie, I just sent you an email with more information about what to look for. I hope it helps, Melissa
Hello, long-time sufferer of cystitis here. Was given antibiotics maintenance dose for 2 years by the drs but did nothing to stop the debilitating flare ups. D mannose was my saviour please try it if you haven’t yet. You start with the treatment dose with a flare up and then continue with maintenance dose (I continued with this dose until I basically forget all about cystitis being a part of my life). D mannose and hot water bottle were my saviours in some dark days. If you’ve tried it and it’s not worked maybe try a different brand just incase the quality is the problem. Good luck all
Hi Chloe, thanks for sharing your experience. I’m so glad you have found D-mannose helpful. As mentioned in the article, it has only shown promise for E. coli and possibly some other gram negative bacteria. For people with a UTI caused by other organisms, it is unlikely to help. This is why it’s so important to work with a competent clinician. I hope you reach a full resolution of your symptoms! Melissa
Hello 🙂 unfortunately I have been suffering from UTI for years. I have recently started taking D-mannose and I can tell that it helps a lot. However, I am still experimenting and I dont know the correct dose to treat UTI and to prevent it (especially after intimacy). I am taking 3g per day to treat my current UTI however I am scared to lower the dose as you wouldnt know if e-coli bacteria is still present in the bladder. I am concerned that taking d mannose might add to my weight. Are there any concrete studies which show that D Mannose will not contribute to weight gain? Thanks a lot for this website. Usually GPs treat it with antibiotics and they make everything worse. Thank you.
Hi Amanda, we haven’t seen any studies that specific look at d-mannose and weight gain, though they may exist. Research does suggest that the human body can’t metabolize or store D-mannose and that any effect on blood sugar levels should be minimal. If you come across any relevant studies, I’d love to hear about it. Melissa
Hi, thank you for the great article. I have a question does d-mannose make candida worse? And please can you share with me the brand you are using 🙂 thanks ♥️
Hi Mariam, I emailed you with more info about D-mannose and other supplements that may be helpful. I haven’t come across any solid research into whether D-mannose impacts candida. It’s a great question and one I would also like a definitive answer on. Melissa
I’m wondering If taking strong dosages of D-Mannose to treat UTI (i.e. 2 capsules 2X/day as per instructions on the bottle), can bring on a strong incidence of Atrial Fibrillation (I experienced it this morning so strongly I had to get out of bed). I am backing down on the D-Mannose to 1 capsule 2x/day just to be on the safe side)
Hi Lynn, we haven’t seen any studies that list this as a possible side effect yet, but the research into D-mannose is still quite limited. I will definitely keep an eye out for more information on this. Melissa
Thanks Melissa! By taking only 1/2 the suggested dosage, my Atrial Fibrillation disappeared.
Hi Lynn, I’m glad you’re feeling better! Melissa
How much D-Mannose would it take to eliminate a bladder UTI? How long and what would be the daily dosage?
Hi Richard, studies into D-mannose have looked at it as a preventative measure for UTI, and we need more research into its potential as a treatment. Many people start with the dosages recommended on the product (which are based on the available studies), then vary their dosages, according to their symptoms. It’s always best to speak with a practitioner about this of course. Melissa
Just discovered your website and very impressed/encouraged by your objectivity and practicality.
You made a comment that D-mannose stops adhesion of (various stuff) and reduces symptoms but does not kill bacteria. Thus, if bacteria are identified, does this imply that D-mannose is a band-aid (treating symptoms) and something else is needed to get to the root of the issue?
Thank you.
Hi Howard, to our knowledge, D-mannose hasn’t been studied UTI treatment, but rather as a preventative measure. This means it’s difficult to answer the question. The theory of preventing adhesion of E. coli to the bladder wall could potentially be applied to treatment. That is to say, as the bladder lining naturally sheds over time, any infection in the bladder lining may also be sloughed off and D-mannose may help to prevent re-adhesion of E. coli, which may result in the eradication of infection over time. There have been no studies that confirm this theory, and we have no indication of exactly how much D-mannose would be required and for how long (if it actually works in this way). It’s also important to acknowledge that UTIs can be caused by many other bacterial species. Melissa
Dear all, I have just found the website today and it is good to know I am not alone in this! I have been fighting UTI for 13 years now (since 19), with some happy years almost without it (4?), when I took D-mannose. But this year it is here again and D-mannose is not working any more for me (I take 2grams twice a day). So I will look more on your tips about diet and probiotics, I really hope I can solve this one day…
I am now on day 3 of D-Mannose and have stopped the prophylactic anitbotic! I am
Hoping for a miracle!
Hi Danica, I hope you find some answers soon! If there’s anything we can help with you’re always welcome to send us a direct message. Melissa
Hello! Any recommendations if you have enterococcus? Thank you
Hi Alyssa, I saw you also sent us a direct message, so I’ve replied with more info by email. Melissa
After having UTIs for the last 10 year, getting worse and worse in the last 4, I found D-mannose 2 years ago. It is currently the only thing keeping me going and I take it daily. I did notice I was getting severe bloating which would often lead to UTI symptoms very regularly. What I found was that after high carb and high sugar meals/ food this bloating and discomfort would occur. I looked further into D-mannose and found it is also used for obesity to stop the body digesting sugars, and I was concerned that this was causing undigested sugars to pass through my body and stir up bacteria in the gut. I am not on a low carb, sugar free diet and have no bloating and not had a UTI in over 6 months (normally I would be getting them monthly with symptoms almost daily).
What is the best d mannose brand to get?
Hi Deb, I saw you also sent us an email so I’ve replied there with more information. Melissa
Please tell me which brand you are using. Thank you.
Hi Susan, I just emailed you more information. Melissa
Hi Jenny, that’s so great to hear that D-mannose has been helpful for you. Thanks for sharing your experience. Melissa
I have had severe UTI’s for years. Started taking D mannose a year ago and it is tremendous. My uti’s were always e coli related. I take 1000mg capsule daily and if I do get a UTI which is now very rare I take 2000mg 3x a day and within 2 days it’s gone! I would recommend trying D Mannose to anyone who suffers with UTI’s.
Hi, could you recommend the brand of D Mannose you take?
Would love to know which brand you use, could you send me an email to share? thanks!
Hi Nicole, I just shared the same information with you. Melissa
Hi Jessica, I’ve sent you an email with some information. Melissa
Hello! I would also love the specific brand of D-Mannose you have used and/or recommended? Thank you so much! ☺️
Hi Tabby, I saw you also sent us an email so I’ve replied there with more info. Melissa
Hello would you please send me the brand that you are using so that I may purchase, thank you!
Hi Jo, I just sent you an email with some more information. Melissa
Hi Lisa, that’s great to hear you’ve found D-mannose helpful. I hope it’s possible with time to find a complete resolution, as tricky as recurrent UTI can be! Melissa
There is a study about the contraceptive effect of D Manosse so I think is not a good idea to take while you are trying to get pregnant. I got Cándida when I took it, it may had been coincidence
I am only now reading this informative article. Please may I also have the brand of D Manose that is the purest safest. Thank u
Sure thing. I just sent you an email with more info. Melissa
Hi Adriayala, you’re right, we need much further research into the safety of D-mannose during pregnancy, and into its potential impact on fertility. If you have a link to the study you mentioned, can you share it here? It may be helpful for others. Melissa
Of course, https://patents.google.com/patent/US6753319B2/en
Thanks! I see this is a patent rather than a study, but for anyone interested in the studies it’s based on, scroll down to the ‘Non-Patent Citations’. Melissa
I tried d-mannose for an extended period of time. Two different brands actually. I had breakthrough UTI’s with both brands while taking it consistently every day at the recommended dose. Both were tested and came back as cause by e-coli bacteria. Obviously it’s not effective for everyone.
Hi Lacey, you’re exactly right. There is no single UTI therapy that will work for everyone and more research is needed into D-mannose, to better define where it may and may not be beneficial. Melissa
I used D-Mannose successfully last year and I would estimate that it put off a re current infection for up to six months once I stopped. Having read the above article I am inclined to take it regularly as a treatment and preventive measure. I took it in combination with high dose Vitamin C which does kill the bacteria. As you say, the D-Mannose does not. It will be costly. A month’s treatment here costs €40! However, so do beauty treatments! I know which I would rather have. I will keep you informed on progress.
Hi Patricia, that’s great to hear it’s been working for you. Thanks for sharing your experience, and do keep us informed of your progress! Melissa
Thank you for the great breakdown of D-mannose use in UTIs. I currently want to try in my 3 y/o daughter, who has all the symptoms of a UTI. We have an appt with the doctor in 2 days, but if I can help her while we wait, or even avoid antibiotics altogether, that’d be great.
My question is: how do you adjust the dosage for a child? I have searched everywhere and cannot find specific instructions for how to do this. Please help- it would be so appreciated!
Hi Shira, dosages for D-mannose are usually based on manufacturer recommendations. The research into D-mannose is limited and I haven’t come across any information specifically for children. It’s best to speak with a doctor or a functional medicine doctor or naturopath that is familiar with D-mannose and can help. Sorry we can’t be more specific. Melissa
Thanks Melissa. Apparently, no one knows. And haha about asking my doctor- when I told her I started D-Mannose while waiting the 2 days for an appointment, she asked me what that is! She had never heard of it before. Anyway, I wish I could find more accurate dosing for kids. Been giving my daughter about 1/2 the adult dose, but she is getting gas, so I will cut down even more. Thanks for the response though.
Hi Shira, I hope you find some answers soon. Melissa
Try avoiding baths, esp with any products in them. Worked for me for years, allergy to perfumes apparently?
Hi Anne, it’s true that some people experience chemical sensitivities that can cause UTI-like symptoms. We’ve covered this more in our UTI prevention article. Thanks for sharing your experience! Melissa
You state “The best way to establish the effectiveness of D-mannose is m”ltiple large-scale, randomized, placebo-controlled, double-blind clinical trials.” However, you failed to mention that the likelihood of this is very poor. Since it’s a non-patentable substance, no drug company is going to pony up for such testing. Which leaves it up to government or universities to take on. And considering the cost, we all know that isn’t very likely. So for now, positive reviews and recommendations are probably the best we can expect.
Spot on, Sonia! No one is going to pour money into researching an inexpensive, non-patent-able, food-product cure! Much more lucrative to push the antibiotics…even if they are starting to see that drug resistance is a real problem. Sad but true 🙁
Hi Sonia, you are right, it is unlikely that most non-pharmaceutical compounds will ever be researched in the kind of depth we’d like to see, however, there are researchers looking at different angles of recurrent UTI, and we’ll continue to support these efforts. Melissa
I had recurring uti every month for a year, and was hospitalized three times from reactions to antibiotics, and bacteria getting into my bloodstream and heart. A leading researcher who specialized in recurring uti put me on dmannose. It did not work at first, so I had to up my dose to 3 times a day. It worked. I have only had one uti in the past year.
To California Girl – Can I ask what your symptoms were when the bacteria affected your heart? And do you know which specific bacteria affected your heart? Earlier this year I had tachycardia and an echocardiogram revealed pericardial effusion. I was hospitalized, but had no procedure to test the fluid around my heart (thank God!). I had had an agonizing UTI at the onset of the tachycardia (Later, a microgen test revealed I had strep and e. coli). I haven’t found anyone else whose bacteria affected their heart – not even sure this is the case with me – and so I’m very curious about your situation. Take care
That’s great to hear that it’s working for you! Melissa
Hello Melissa,
Thank you so much for sharing your experience. I have also been struggling with reoccurring UTI. Would you mind share the dosage and brand of dmannose you used? Do you take in in pills or powder form. Thank you!
Nancy
Hi Nancy, I didn’t use D-Mannose in this way myself, I think you’re referring to the comment above. We don’t recommend brands on our site. Many people that reach out to us have said they’ve experimented with dosages to find what works for them (and if it works). Melissa
Thank you for this wonderful site.
Humans make d-mannose from glucose internally. If we cannot do this, we have carbohydrate-deficient glycoprotein syndrome and massive problems long before UTIs. Mpi-hypomorphic mice are genetically modified to mimic of humans with this issue.
An mpi-hypomorphic mouse fed d-mannose will produce blind babies. Bees that are fed 100% d-mannose die.
For “normal” humans it is not clear that (i) mice that are genetically modified to derail glycoprotein processing, or (ii) bees being fed 100% d-mannose, are good analogs.
An unqualified statement that d-mannose is “toxic to honeybees and it can blind baby mice” may cause unwarranted concern for a person with normal metabolism.
Might you clarify it?
I love this site!! I had recurrent utis for 2 years. I never EVER had a break, I was on low dose antibiotics, cranberry pills, prebiotics, and I didn’t drink anything but water. My boyfriend found D-mannose for me one day and I was skeptical and said don’t even waste your money it won’t work but he ordered it anyway and THANK GOD he did. I stopped having utis when I started taking them. I actually ran out and cldnt get any for a week or so and I ended up having a uti! I got them back and started taking them again and it went away! I love that this article goes so in depth and explains everything!
Hi Elizabeth, I’m happy to hear you’ve found something that works for you. That’s great news! Melissa
Hi George, thanks for pointing this out. I’ll pass your suggestion on to the author of this article so she can guide any changes. Melissa
Does D Mannose help to clear infections with klebsiella pneumoniae, enterococcus faecalis, or group b strep? Or does it only effect E. Coli? I’ve seen online that it only effects E. Coli, but this article seems to imply it would help with the others as well? Is there any chance the sugar would feed a Klebsiella or enterococcus or even group B strep infection?
I was told to start taking D-Mannose by the urologist after a cystoscopy to investigate recurring UTI’s. Antibiotics had stopped working for me after repeated use over the previous year. I have been taking it for 5 months and so far it’s been fantastic. I take it three times a day and cut out caffeine from my diet. I probably won’t ever give it up now.
Hi Julia, it’s great to hear you’ve found something that works for you! Thanks for sharing your experience. Melissa
Thank you so much for this article and your site. I’ve been taking 2-3g per day of d-mannose for three years and think I will probably always! I am using Now brand and am wondering if you have any recommendations for what brands offer naturally produced D-mannose? Thank you again.
Hi Amy, I’m so glad to hear you’ve found something that works for you! One brand we’ve had good feedback about and that sources naturally is here. We don’t recommend specific products ourselves. Melissa
Hi Amy, We have seen some suggestions that D-mannose may also be beneficial for other gram negative bacteria, however, we haven’t come across any solid research on this. If you find any we should be aware of, please send it our way. Some people find diet impacts their symptoms, however, we also have not yet found any reliable research on this. Melissa