Fructose malabsorption (intestinal fructose intolerance) causes problems for the affected person in terms of digesting fructose.

Fructose is a monosaccharide that occurs naturally in foods from plants, such as fruit and vegetables. Fructose is contained in fruit juices and sweets, and is part of ordinary household sugar.

Fructose is normally absorbed from the intestines into the blood via special transporter proteins in the intestinal mucosa. However, if these transporters are not working properly, the fructose cannot be resorbed or can only be absorbed incompletely, i.e. absorbed into the bloodstream.