Department of Food and Nutrition Services,
University of Iowa Hospitals
and Clinics
Peer Review Status: Internally Peer Reviewed
Creation Date: May 2004
Last Revision Date: May 2004
What is DFI?
DFI is the inability to absorb fructose efficiently. Fructose is broken
down by bacteria into short chain fatty acids, carbon dioxide and hydrogen. Fructose
is associated with low plasma folic acid concentrations, low serum tryptophan
and zinc, moderately elevated serum amylase and lipase concentrations, elevated
plasma and liver triglyceride, hepatic lipogenesis, fatty acid oxidation, mental
depression, and lower Vitamin C, Vitamin E and glutathione activities.
Hereditary Fructose Intolerance (HFI) should not be confused with Dietary Fructose
Intolerance. HFI is a deficiency of a hepatic enzyme (fructose-1,6 diphosphatase)
causing acute inhibition of hepatic glucose output when fructose is ingested. HFI
leads to hypoglycemia, acidosis, accumulation of gluconeogenic precursors, enlarged
liver and mental retardation.