Fructose malabsorption may be caused by deficient fructose carriers in the small intestine’s enterocytes. This results in an increased concentration of fructose in the entire small intestine. Fructose is a sugar that is found in many foods, usually fruits, honey, processed foods and foods with high fructose corn syrup and even some vegetables. Fructose is also found in table sugar, comprising 50% of it, with the other component being glucose.
Some people cannot completely absorb fructose in their small intestine. The excess, undigested fructose attracts water, often leading to diarrhoea. Additionally, the undigested fructose is then carried to the large intestine or colon, where normal bacteria rapidly break it down. The breakdown of fructose in the large intestine causes bloating, gas, and other symptoms.