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What is D-mannose?

What is D-mannose?

What is D-mannose?

D-mannose is a simple sugar found in foods like cranberries, blueberries, peaches and apples. Small amounts of D-mannose are also found in the body. When extracted for medicinal uses, it yields a white powder that is mildly sweet with a slightly bitter aftertaste. D-mannose is well known as a supplement that helps reduce the risk of recurrent UTIs in women.

The evidence for D-mannose?

Limited in-vitro research has demonstrated that D-mannose can adhere to E. Coli., the most common bacteria linked to urinary tract infections, thus preventing them from sticking to the lining of the bladder. A 2013 clinical trial evaluated D-mannose in 308 women who had frequent UTIs. D-mannose was almost as effective as the antibiotic nitrofurantoin for preventing UTIs over a 6-month period. In a 2014 study, D-mannose was compared to the antibiotic trimethoprim/sulfamethoxazole for treatment and prevention of frequent UTIs in 60 women. D-mannose reduced UTI symptoms in women with an active infection. It was also more effective than the antibiotic for preventing additional infections. A third 2016 study tested the effects of D-mannose in 43 women with an active UTI. At the end of the study, most women had improved symptoms.

How to Use D-mannose

D-mannose can come in different forms – as a powder, which easily dissolves into water or in capsules, if preferred. In some cases it will be mixed with cranberry concentrate powder for a synergistic effect. Since D-mannose is a simple sugar, it does not have to be taken with a meal.  For best results, the powdered form should be consumed immediately after mixing. Having pills available at home and/or work, or to carry along, can help make sure you don’t miss a dosage if making a drink is not convenient or missed. Whether using the pill or powdered form, be sure to drink plenty of water (ideally 1-2 cups per dose) to help flush the bladder and kidneys. D-mannose may be safely used with other recommended natural remedies such as Vitamin C and probiotics.

  • Using for prevention: For prevention of UTIs, Health Canada recommends a dosage of 2 grams (2000 mg) taken once daily.
  • Suspected UTI. It is common practice to increase the dosage to 3 grams daily, in divided doses, in the case of an active or suspected UTI. This high dose is often continued for a couple of weeks. It should be noted that D-mannose has no antibiotic properties and may not kill existing infections. If you have persistent burning and/or urgency symptoms, it is recommended to seek professional medical advice.

Can Diabetics Use D-mannose?

Because insubstantial amounts of D-mannose are used by the body, it is unlikely to interfere with blood sugar regulation. This makes D-mannose a viable alternative to cranberry juice. Diabetics should still monitor their blood sugar and watch for potential fluctuations, as each individual is different in how they may respond.

Other Safety Considerations

Most individuals do not suffer any side effects, but some individuals may experience loose bowels or diarrhea. Safety during pregnancy and breastfeeding has not fully been established, so it is recommended to consult a health care practitioner prior to use.

Consider the Quality of your D-mannose

NOW® is the only company offering organic D-mannose. Furthermore, our mannose is carefully analyzed to determine its purity. This is to ensure there’s no dilution with other sugars, such as dextrose or sucrose. NOW® specifies that our D-mannose will exceed 99% purity and taste mildly sweet with the slightest hint of a bitter aftertaste. We add no fillers, flow agents, or excipients, so you receive pure D-mannose in our powder products. We provide both powder and vegetarian capsule versions to fit your lifestyle.

Coauthored by Brett Kelly, BSc. and Thalia Charney, MA, Holistic Nutrition and Wellness Coach
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