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Some research suggests that the supplement D-mannose may be able to help treat urinary tract infections.

D-mannose is a type of naturally occurring sugar. There is ongoing research on its uses, which may include the treatment of urinary tract infections (UTIs).

This article looks at what D-mannose is, how it may interact with UTIs, and its side effects and risks.

A peach being sliced which contains D mannoseShare on Pinterest
D-mannose naturally occurs in oranges, apples, and peaches.

D-mannose is a type of sugar that some people believe may help treat UTIs.

It may work by making it more difficult for the bacteria that are responsible for UTIs to attach themselves to the urinary tract.

D-mannose naturally occurs in a variety of fruits and vegetables, including:

  • oranges
  • apples
  • peaches
  • cranberries
  • mangos
  • aloe vera
  • seaweed

Historically, people have used D-mannose to treat UTIs in animals. Now, scientists are interested in whether it could also treat and prevent UTIs in humans.

According to a 2017 study, women with recurrent UTIs usually receive a low-dose antibiotic for 6 to 12 months after infection. While research has proven this to be effective, there is a risk that long-term antibiotic use will increase the likelihood of bacteria becoming resistant to antibiotics.

For this reason, scientists are trying to develop nonantibiotic treatments for common bacterial infections, such as UTIs. D-mannose may be one possible treatment.

UTIs occur when bacteria infect a person’s urinary tract, which includes the kidneys, bladder, and urethra.

According to the Office on Women’s Health, the most common UTI occurs in a person’s bladder. This UTI is sometimes called cystitis. UTIs are more likely to affect women than men.

UTIs can cause the following symptoms:

  • pain when urinating
  • a frequent urge to urinate
  • feeling tired, shaky, or confused (especially for older people)
  • cloudy or foul-smelling urine

It is common for UTIs to recur, with 40 percent of women getting another UTI within 6 months of the previous one.

A growing body of research suggests that D-mannose may have a part to play in treating active UTIs and preventing them from developing in the future.

Research into D-mannose for treating UTIs in people is still very new. For example, a 2013 review article noted the lack of clinical studies evaluating whether D-mannose could prevent UTIs from recurring.

Since then, journals have published some small studies, and researchers are currently conducting larger, more rigorous studies.

A 2014 study in the World Journal of Urology found that D-mannose may be effective in preventing people from getting further UTIs after they have recovered from one. In the study, D-mannose was slightly more effective than the antibiotic Nitrofurantoin.

However, the study participants knew whether they were taking D-mannose or not. This awareness might have affected their perception of how effective it was.

A 2016 pilot study found evidence to indicate that D-mannose may be an effective treatment for UTIs and could also prevent them. However, the authors noted the need for further research to confirm this.

The United Kingdom National Institute for Health Research are currently funding research on the link between D-mannose and recurrent UTIs. They plan for the study to involve 508 women, half of whom will receive D-mannose supplements, while the other half will receive a placebo. The study will conclude in 2020 and may provide more insight into how D-mannose affects UTIs.

More studies are necessary to determine whether or not D-mannose is a useful treatment for UTIs. Without these studies, it is not clear what the dosage of D-mannose should be or whether it may interact with other medications or cause side effects.

In one study, the only side effect that some of the participants taking D-mannose supplements experienced was diarrhea. However, researchers noted that the diarrhea was not severe enough for them to stop taking the supplements.

Another article suggested that taking D-mannose supplements may cause complications for women who are pregnant or have diabetes.

It is essential to speak to a doctor before taking any new supplements.

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It is best to speak to a doctor before taking D-mannose.

Due to the lack of research to date, it is difficult to determine either the right dosage of D-mannose or the form that people should take it in.

It is likely that the correct dosage for treating an active UTI will differ from that for preventing UTIs from recurring.

In one study, participants who had received initial antibiotic treatment for a UTI drank 2 grams of D-mannose powder dissolved in water each day for 6 months.

This quantity seemed to be effective and safe. However, without further research, the optimal dosage remains unclear. As a result, it is advisable to speak with a doctor before taking D-mannose supplements.

D-mannose seems to have potential as a UTI treatment. However, the research that indicates this is still very new. Larger, more rigorous studies are necessary to confirm these initial findings.

More research can help provide accurate information about the potential side effects and risks of D-mannose, as well as confirming an appropriate dosage.

Until then, it is vital to speak to a doctor before taking D-mannose supplements.

D-mannose is available in some health food stores and online.