D-mannose

Also known as d mannose, mannose.

Last reviewed October 9, 2026 · Jump to references

What is D-mannose?

In plain words

D-mannose is a simple sugar found naturally in the body and some foods. The body uses it to help make sugar-coated proteins, and some leaves the body in urine. Researchers study whether it can keep certain bacteria from sticking to the bladder lining. Although this idea has attracted interest, a large study found it did not prevent repeat urinary tract infections in women.

Technical definition

D-mannose is a naturally occurring six-carbon monosaccharide and C-2 epimer of D-glucose that participates in glycoprotein synthesis; some absorbed D-mannose is excreted in urine. It binds the FimH adhesin on type 1 fimbriae of certain Escherichia coli strains, potentially interfering with bacterial attachment to urinary tract cells rather than killing bacteria. It is marketed as a dietary supplement, not an FDA-approved treatment for urinary tract infections, and a large placebo-controlled trial did not demonstrate benefit in preventing recurrent infections in women.

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Evidence by use

Each use is rated on its own. There is no single overall effectiveness score.