Articles
Fructose malabsorption
Last updated: 16/01/2010
Lactose intolerance is a common and well known condition in which a person lacks appropriate levels of lactase, an enzyme required for the breakdown of milk sugar lactose. For these people eating lactose can cause symptoms of bloating, stomach cramps, loose stools, nausea and flatulence. A much less well known condition, although similar to lactose intolerance, is fructose malabsorption. In fructose malabsorption a persons ability to absorb fructose, fruit sugar, is impaired. This results in fructose passing through the intestines and being fermented by bacteria, causing both gastrointestinal symptoms (abdominal bloating/cramps, constipation, loose stools, diarrhea or flatulence) and increased proliferation of certain intestinal bacteria and yeast which metabolise fructose.
Signs/symptoms of fructose malabsorption.
- Gas
- Bloating
- Abdominal pain/discomfort
- Diarrhea
- Constipation
- Nausea
- Floating or oily stools
- Some fruits (e.g. apples or pears) causes one or more of the following - Abdominal bloating/discomfort, loose stools, diarrhea, flatulence, constipation or nausea
- Hypoglycemia
Who has fructose malabsorption been identified in?
Dr. Kenny De Meirleir reported at a 2007 Australian ME/CFS conference that of around 400 patients tested, around 45% had fructose malabsorption. Studies available at PubMed report a significant subgroup of people with Irritable Bowel Syndrome (IBS) have fructose malabsorption. It appears to be very common and should be considered in everyone with intestinal symptoms. Some people are asymptomatic, in terms of obvious gastrointestinal symptoms. In these individuals it is likely to be negatively influencing intestinal ecology so is still of clinical significance.
How is it diagnosed?
Fructose malabsorption is diagnosed via a hydrogen breath test. It is a similar test as used to diagnose lactose intolerance. Breath hydrogen measurements are taken fasting, 25 grams of fructose is administered and breath hydrogen levels are monitored regularly for 2-3 hours.
Testing availability.
Check with your local laboratories. Ask if they do hydrogen breath testing for lactose intolerance. If they do then you should be able to do the test for fructose malabsorption.
Perth Medical Laboratories (PML) is the only lab in Western Australia which does this test. The test is done in Melbourne at Box Hill Hospital - Ph: (03) 9890 2666, Email: bookings@breathtest.com.au.
Recent case study.
The following is from a 10 year old who's original health issues included ADHD, anxiety & depression.
- "Thought I would update you on how Matthew is going. The fructose Malabsorption diet seems to have certainly made a huge difference with Matt's constipation. He has gone from depending on a very high daily dose, to having had no magnesium at all for nearly two weeks now, & is going to the toilet every day, at least once."
More information.
- Fructose Malabsorption and Symptoms of Irritable Bowel Syndrome: Guidelines for Effective Dietary Management.
- Fructose Malabsorption Product Guide. This very helpful A4-size spiral bound product guide is the only comprehensive list of suitable commercially available foods. Written by Sue Shepherd, dietitian specialising in fructose malabsorption and irritable bowel syndrome.
- Wikipedia on Fructose Malabsorption.
Blake Graham, BSc (Honours), AACNEM
Clinical Nutritionist
Perth, Western Australia
Phone/Email: See Contact page
*Non-Perth residents may enquire about phone consultations.
