Dietary Fructose Intolerance

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 are the symptoms of DFI?
Bloating
Abdominal pain
Diarrhea
Headache
Weight loss
Fatigue

How is DFI diagnosed?
DFI is diagnosed with hydrogen breath tests. Those include:

• Glucose Breath Test to rule out bacterial overgrowth.
• Lactose Breath Test to test for intolerance to milk and milk products.
• Fructose Breath Test to determine intolerance to fructose.
• Sucrose Breath Test if indicated from physical and oral history.
• 3C stable Radioisotope; Breath tests for children and pregnant women.

How are results of the tests interpreted?

• 10 20 H2, ppm (depending on facility) above baseline indicates a positive result.

How does someone prepare for the tests?
Preparation is vital to the success of the tests. Indiscretions can result in either a false positive or false negative test.

• Do not smoke or perform physical exercise two hours before testing to avoid hyperventilation.
• Rinse mouth with antibacterial mouthwash before testing to prevent premature hydrogen or carbon dioxide production.
• Eat/drink only the following foods 24 hours before testing:
  • White bread (limit to 6)
  • White potato
  • White rice
  • Chicken breast
  • Turkey breast
  • Tea
  • Water
    

What causes DFI?
As yet there are only theories. Some of those are:

• Abnormalities in GLUTE5, a fructose transporter
• Bacteria
• Celiac Disease (transitional)
• Chemotherapy (transitional)
• Familial predisposition
• Injury to the intestinal lining
• Overuse of High Fructose Corn Syrup (HFCS)
• Radiation
• Motility problems
  • Rapid gastric emptying of liquids
  • Rapid intestinal transit
    

What is the treatment for DFI?
There currently is no specific enzyme developed to break down fructose. Until an enzyme is developed the only treatment is to follow the diet and include dextrose (a simple sugar) with your food.

Title Page