Principal Proposed Uses:
Mannose is a “six-carbon-sugar,” as are the better known and closely related substances glucose and fructose. Relying on evidence that is both exceedingly preliminary and highly inconsistent, some alternative medicine practitioners have popularized mannose as a treatment for urinary tract infections.
Mannose plays an important role in human physiology. However, there is no nutritional need for this substance, as the body can easily produce it from glucose. Nonetheless, significant quantities of it can be found in many fruits and vegetables, including peaches, apples, blueberries, green beans, cabbage, and tomatoes.
A typical recommended dose of mannose for the treatment or prevention of bladder infections is 1.5 g daily, often divided into three doses of 500 mg each.
The idea that mannose supplements can help prevent or treat bladder infections derives from a property of the E. coli bacteria. E. coli is one of the common causes of bladder infections. Many, though not all, strains of E. coli have the ability to attach to the mannose present in the wall of the bladder by means of thread-like structures called pili. This process of attachment allows them to initiate the process of infection.
Reasoning from this fact of basic science, medical researchers in the 1980s hypothesized that consumption of mannose as a supplement will increase levels of mannose in the urine to such an extent that this free mannose will saturate the E. coli’s mannose-binding pili and thereby make the bacteria unable to grapple onto the cells of the bladder wall.
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The bottom line: There is no meaningful scientific reason to believe that mannose is useful for the prevention or treatment of bladder infections.
- Reviewer: EBSCO CAM Review Board
- Review Date: 09/2014 -
- Update Date: 09/18/2014 -