D-Mannose side effects

Are there any possible side effects to adding d-mannose to my diet?

What is d-mannose?

In this blog post we ask what are the possible side effects of adding d-mannose to our diet. D-mannose is a simple glucose naturally present in fruits such as cranberries.   Ninety percent or more of Urinary Track Infections (UTIs) are produced by the bacteria E. coli. Although D-mannose is reputed to eliminate UTIs as quickly as conventional antibiotic drugs, it is significantly trustworthy because it does not kill E. coli.  Instead d- mannose is said to attract E. coli bacteria sticking to the lining of the urinary system, which allows the regular flow of urine to wash the e-coli bugs down the drain.

Picture the E. coli in the urinary tract.  Those sweet little mannose substances they crave are present not merely on the surface of the epithelial cells but surrounding them in the urine as well. The E. coli can not change without bumping into D-mannose "just floating around" in the urine. Incapable of resisting the delicious bait they suddenly find themselves swimming in and they would latch on to the nearest mannose elements, and happily sail off into the porcelain sun. Those few E. coli left sticking to mannose molecules on cells then become easy victims for white blood cells.

How common are UTI's

Urinary tract infection (UTI) is the third most common infection in humans. New resisted strains of uropathogens have been developed due to different factors such as widespread use of antibiotics.

What are the possible side effects of adding d-mannose to your diet?

Side effects are not common when taking d-mannose at the recommended servings.

Unwanted side effects of D-mannose may include;

Bloating, a feeling of fullness in the stomach, can make you uncomfortable.  Or passing of wind.  It is best to stick to the recommended serving of this food supplement to avoid this.

Loose stools can occur if you are taking more than the recommended serving.  

Is D-mannose okay for individuals with diabetes?

Some research suggests that D-mannose might make blood sugar control more difficult in people with diabetes.   Seek medical advice.

Pregnancy and breast feeding

If pregnant may become pregnant or breast feeding consult your healthcare professional before using.


1. Harrington RD, Hooton TM. Urinary tract infection risk factors and gender. J Gend Specif Med. 2000;3:27-34.

2.  Ghorbani A, Ehsanpour A, Roshanzamir N, Omidvar B. Alterations in antibiotic susceptibility of urinary tract infection pathogens. J Nephropathology. 2012; 1(1): 43-48. DOI: 10.5812/jnp.8

3.  Schaeffer AJ, Chmiel JS, Duncan JL, Falkowski WS. Mannose-sensitive adherence of Escherichia coli to epithelial cells from women with recurrent urinary tract infections. J Urol 1984;131:906-10. View abstract.

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