Maybe It Is Something you Ate – Fructans

March 22, 2012 by foodworksblog 6 Comments

Русский: Цикорий обыкновенный English: Chicory Latina: Cichorium intybus (Photo credit: Wikipedia)

By Sally J. Feltner, PhD, RD

Troubled by gastrointestinal problems and are you thinking of trying a gluten-free or wheat-free diet?  Before you do, consider another cause – Fructans.

Fructans are oligosaccharides (small number of sugar units) made of fructose molecule chains that are not completely absorbed because the small intestine lacks enzymes to break their fructose-fructose bonds. Fructans then go to the colon to stimulate the growth of “friendly” bacteria.  These resident bacteria then break down fructans and for this reason, can contribute to bloating, gas, and pain.

Wheat accounts for the majority of people’s fructan intake. In addition, to provide more fiber in the American diet, food manufacturers are including many functional fibers, including inulin into many foods.  Inulin is a soluble dietary fiber found in onions, leeks, garlic, asparagus, bananas, artichokes and chicory root extract.  Commercial inulin is primarily produced from chicory root.

Inulin also can be found in high fiber breakfast bars, ice creams, and beverages among other processed foods. The label may list inulin, chicory root extract, oligosaccharide, or oligofructose. For example, the Fiber One Chewy Bar with 9 grams of dietary fiber lists chicory root extract as its top ingredient.

A recent study was designed to assess just how much inulin was tolerated by 26 healthy men and women aged 18 to 60. After a night of fasting, once a week for five weeks, participants were fed a breakfast of a bagel with cream cheese and orange juice. The orange juice was mixed with a placebo or with 5- or 10-gram doses of two commonly used inulin products — native inulin and shorter-chain oligofructose.

After each “fiber challenge,” participants were called several times over two days and asked about symptoms such as gas/bloating, nausea, flatulence, stomach cramping, diarrhea, constipation and GI rumbling.

Those that got any dose of inulin generally reported mild symptoms.  The people who received the 10-gram doses reported the highest scores in every symptom except constipation.

The authors concluded that most healthy people could tolerate up to 10 grams of native inulin and 5 grams of the shorter chain inulin a day. Although the authors reported no potential conflict of interest, the research was funded by Cargill, Inc. a maker of inulin food additives, which provided the product used in the study.

Gastointestinal Tolerance of Chicory Inulin Products, Journal of the American Dietetic Association 2010; 110: 865-868.

In another study presented at the Australian Cereal Chemistry Conference (2005), fructans as inulin and fructo-oligosaccharides were found to trigger the symptoms of abdominal pain, discomfort and irregular bowel habits in 3 out 4 patients with irritable bowel syndrome (IBS) and in some patients with Crohn’s disease.

Fructans exacerbate gastrointestinal symptoms in irritable bowel syndrome and Crohn’s disease, J.G. Muir, S.J. Shephard, O.R. Rosella, P.R. Gibs; Monash University, Melbourne, Australia.

For IBS patients or anyone with recurring gastrointestinal symptoms, it is generally recommended that you consult your doctor and discuss keeping a food diary of foods eaten and any related symptoms. Take note of foods that seem to be followed by symptoms that occur within 1 to 3 days.  In addition to fructan or gluten-containing foods, pay particular attention to milk, lactose, fructose, sorbitol (found in sugar-free candy and gums) as well as gas-forming foods, wheat, fat and coffee. To test a diet change, you should follow it carefully for 2 weeks and then return to the previous diet

The Role of Diet in Symptoms of Irritable Bowel Syndrome in Adults: A Narrative Review. Journal of the American Dietetic Association 2009;1204-1214

You may want to consult a registered dietitian or check out a book written by Patsy Catsos, MS, RD, LD, IBS-Free At Last!.  You can visit Patsy at www.ibsfree.net.