hereditary fructose intolerance

Hereditary fructose intolerance (HFI) is a metabolic disorder caused by a deficiency in the liver enzyme fructose-1-phosphate aldolase. This deficiency prevents the proper breakdown of fructose, which is found in fruits, sucrose (table sugar), and some infant formulas.1

Symptoms typically appear after fructose ingestion and can include poor weight gain, vomiting, low blood sugar (hypoglycemia), liver dysfunction, and kidney problems. Children with HFI often develop an aversion to sweet foods. The condition is manageable with a diet that excludes fructose and sucrose.1

It is important to distinguish HFI from fructosuria, a milder condition where the enzyme fructokinase is defective, leading to increased fructose in the blood and urine but without other clinical symptoms or disabilities.2