What D-Mannose is
D-Mannose is a simple sugar (a monosaccharide) that occurs naturally in some fruits, such as cranberries, apples, and peaches, and is also made in small amounts by the body. It is sold as a dietary supplement in powder and capsule form and is most often marketed for urinary tract health.
Commonly used for
Taken by some people in hopes of lowering the risk of recurrent urinary tract infections (UTIs)Used by some people alongside or instead of cranberry products for urinary healthPromoted as a component of "glyconutrient" supplements marketed for general health and immune support
What the evidence shows
High-quality evidence from authoritative US-government sources is limited, and none of the sources reviewed here affirmatively establish that D-Mannose works for its main marketed use. The NIH Office of Dietary Supplements, NCCIH, and MedlinePlus do not publish a dedicated D-Mannose fact sheet, and the MedlinePlus health topic on urinary tract infections does not mention D-Mannose or list it as a recommended way to prevent UTIs. Memorial Sloan Kettering's About Herbs database lists mannose as one of several monosaccharides found in \"glyconutrient\" supplements and, assessing those products' broad health claims, states that strong scientific evidence to support the claims is lacking; that database does not evaluate D-Mannose as a UTI remedy. D-Mannose is not a treatment for an active UTI, which is a bacterial infection that typically requires medical evaluation and antibiotics.
Typical dosage
There is no established or government-recommended dose for D-Mannose, and the authoritative sources reviewed here do not endorse it for preventing or treating infections. Because a suspected UTI can worsen without proper care, talk to a clinician before using D-Mannose rather than self-treating, and seek medical attention promptly for symptoms such as burning during urination, fever, or back pain.
Safety
As a sugar, D-Mannose is generally regarded as well tolerated in short-term use, but rigorous long-term safety data from US-government sources are limited. People with diabetes or blood-sugar concerns, those who are pregnant or breastfeeding, and anyone with kidney problems should check with a clinician before using it. Tell your healthcare providers about any supplement you take so they can manage your care safely.
Side effects
Reported side effects are mostly mild and gastrointestinal, such as loose stools, bloating, or diarrhea, particularly at higher amounts. Comprehensive side-effect data from authoritative government sources are limited, so individual reactions may not be well characterized.
Interactions & cautions
No specific drug interactions are documented by the authoritative government sources reviewed here, but that absence does not guarantee none exist. Because D-Mannose is a sugar, people taking diabetes medications should be cautious, and anyone on prescription drugs should tell their healthcare provider about all supplements they use.
This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Summarized from public health authorities; general reference, not medical advice. Talk to a licensed healthcare professional before starting any supplement.
