Fructose Intolerance

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What is Fructose Intolerance?

Fructose is a natural sugar found in many of the natural foods, processed foods, and processed beverages that we eat and drink on a daily basis. It is found in honey, fruits, fruit juice, and syrups. It is also found in table sugar (sucrose). Sorbitol is another form of sugar that, when digested, converts into fructose.

What Causes Fructose Intolerance?

Fructose intolerance is a deficiency of an enzyme called Aldolase B, a protein that breaks down sugars. It can be a hereditary disorder and can typically be diagnosed during infancy when a child begins to bottle feed and eat solid foods. Usually those diagnosed at a very young age have multiple medical complications. Fructose intolerance may, however, appear in adulthood without causing severe symptoms but rather bothersome symptoms similar to irritable bowel syndrome, such as abdominal pain, excessive gas, abdominal distention, or diarrhea.

The Hydrogen Breath Test: Testing for Fructose Intolerance

A simple breath test can be done in the office to test for fructose intolerance. The over-production of gasses such as hydrogen is a result of the fermentation of fructose by bacteria in the large intestines. The hydrogen is absorbed through the bloodstream and excreted through the lungs. After you blow through a special device, the Hydrogen Breath Test can allow us to measure the amount of hydrogen in your lungs. An elevated hydrogen level alerts us to the possibility of fructose intolerance.

You must fast for 12 hours before your appointment. We ask that you take your medications as directed with a small sip of water the morning of the procedure. Please advise your health care provider if you are diabetic or if you have been on antibiotics within the last two weeks. You will be given an 8 oz glass of soda to drink. A random breath test will be obtained and you will be asked to return to the office in three hours for another breath test. Detailed instructions will be provided at the time of the appointment.

The Treatment for Fructose Intolerance is Diet Modification

Avoid not only natural foods containing fructose but also processed foods and drinks. Read the food labels for: Fructose, Lactose, Sucrose, or Sorbitol.

  • Fructose
  • Lactose
  • Pancake syrups and corn syrup
  • Table sugar
  • Confectioner’s sugar or powdered sugar
  • Fruit and fruit juices
  • Honey
  • Regular sodas
  • Flavored water
  • Sorbitol
  • Sports drinks
  • Sweetened milk or coffee creamers.

** Consider consulting with a registered dietician for a complete list of foods to avoid.

If you think you might have fructose intolerance, please consult with one of your physicians.