Sorbitol - The Trouble With Sugar Free…

How Sorbitol Causes Diarrhea and Irritable Bowel

If you enjoy sugar-free products contaiing sorbitol - like confectionery, soft drinks and chewing gum - it may be worthwhile to review your eating habits. Research now shows even moderate amounts of sorbitol can cause chaos in the intestine.

Sorbitol is A Common Additive

Did you know the common additive sorbitol causes bloating, flatulence and diarrhea? It only takes 10g per day. Ironically sugar-free products are marketed as being part of a healthy lifestyle.

However - despite more than two decades of clinical research on the detrimental effects of sugar substitutes on the human body, sugar-free products are sold as solutions for everything from weight loss to tooth whitening.

We classify Irritable Bowel Syndrome as a collection of symptoms rather than a disease. 

This article looks at sorbitol, one of the so-called polyols listed on sugar-free packs and used frequently as a softener and sweetener in confectionery.

    • QUESTION: Why do manufacturers continue to market products containing sorbitol at levels known to cause Irritable Bowel Syndrome?
    • ANSWER: Sugar-free products are the darlings of retailers. The tiny packs take up little space at the point of sale. Now enjoying double-digit sales growth, they deliver profit margins which far outstrip chocolate bars or candy (1).

Sorbitol is a natural laxative and occurs in small amounts in pears, prunes and other fruits. In fact sorbitol solution is sold as a laxative through pharmacies (Sorbilax - Pharmacia & Upjohn).


Delayed reactions are confusing


Case study: A flight attendant with troubling diarrhea

Dateline June 1995: The Lancet publishes the case of a 35 year-old flight attendant diagnosed with Irritable Bowel Syndrome. She is admitted to a British Hospital and undergoes a series of gruelling tests: 14 procedures including blood tests, biopsies, liver biochemistry, gastroscopy, endoscopy and periods of supervised fasting.

It eventually it turns out the cause of her diarrhea (up to ten watery motions per day) is the result of habitual use of sugar-free chewing gum containing sorbitol (3).

This is despite clinical results published twelve years earlier (Gastroenterology January 1983) from the Hartford Hospital and University of Connecticut warning that sorbitol causes gastro-intestinal distress in amounts as little as 10g per day (4).


Dateline June 2003: Popular sugar-free fruit pastilles, mints and chewing gum contain sorbitol in rather large amounts (42% - 50%) (5,6). This means a single tiny 25g purse-pack of fruit pastilles contains easily enough Sorbitol to cause gastro-intestinal distress and diarrhea and Irritable Bowel Syndrome.



From 'Special Diet' to Mainstream

Sugar-free is big business. The last ten years has seen a whole new wave of low-joule, so-called tooth-friendly products marketed to mainstream consumers.

Originally marketed only to the Diabetic population, products containing sweeteners like aspartame, saccharin, sorbitol, xylitol, maltitol, mannitol, acesulphame-K, cyclamates and sucralose are now included routinely in Sugar-free jubes, mints, breath fresheners, chewing gum, soft drinks, diet yoghurt, low-joule ice cream and sugar-substitute baking ingredients. Problems arise when people use sugar-free chewing gum or sweets as a habit.

The action of sorbitol is to linger in the gut because it is not digested. Dosing ourselves daily means we are less able to clear sorbitol from our systems: each day it accrues to a greater and greater concentration.


Links to Irritable Bowel Syndrome

Sorbitol is also thought to be a cause of Irritable Bowel Syndrome (2). Most sugar-free products carry warnings like: Excess consumption can have a laxative effect. However, the packs are so small that reading them is difficult, and more importantly the term excess usage is not explained or quantified. Is one pack an excess?

With chewing gum there is even greater danger of sorbitol overdose. The manufacturer of a gum marketed as a teeth whitener (6) encourages consumers to use it many times in a day, presumably to glean as much of the tooth brightening property as possible. Ironically this is claimed by the manufacturer to be a healthy lifestyle activity.

There is no reference on the packaging or manufacturer's website to the laxative properties of sorbitol.

  • So what? you think. We don't swallow chewing gum
  • While gum is not swallowed many of its ingredients are readily ingested and quickly make their way to the intestinal tract.


How Does Sorbitol Cause Irritable Bowel Syndrome?

Firstly, undigested sorbitol in the small intestine acts as a substrate (platform) for the fermentation of bacteria. Hydrogen gas is produced causing abdominal cramps, bloating and severe flatulence. These are also common symptoms of food intolerance.

Secondly, we already know sorbitol in quantities as low as 10g per day causes diarrhea - brought on by the so-called osmotic purge happening in the gut.

Sorbitol is a 'polyalcohol' sugar (many sugars strung together) and is neither digested nor absorbed by the small intestine. It passes unchanged right through to the colon (large intestine) where it drives an osmotic purge (2). This means it leaks through the lining of the intestine wall - causing fluids (mostly water) to pass through in the opposite direction via osmosis. Bowel motions become watery and lead to dehydration and over time, other consequences like malabsorption of nutrients.


Food Manufacturers' Responsibilities - and Consumer Awareness

Here at the Food Intolerance Institute of Australia we are not concerned about the use of artificial sweeteners per se . . . just the large doses available in everyday food products. When this is coupled with the manufacturer's encouragement to use them frequently and make it a habit (as with chewing gums which whiten the teeth, or freshen breath) we believe there is a real health danger for consumers.

We feel there is room for manufacturers to take more responsibility in relation to sorbitol, especially in the light of increased understanding from long term clinical research.

Meanwhile for the consumer, awareness is the only real defence. For those who believe they may have Irritable Bowel Syndrome it may be wise to take a personal inventory of sugar-free foods.



    1. Greaves et al. An air stewardess with puzzling diarrhea. Lancet 1996; 348: 1488
    2. Hyams JS Sorbitol intolerance: an unappreciated cause of functional gastrointestinal complaints. Gastroenterology 1983; 84: 30
    3. Gould et al. Diabetic diarrhea.Curr Gastroenterol Rep. 2009 Oct;11(5):354-9.
    4. Hill DB et al. Osmotic diarrhea induced by sugar-free theophylline solution in critically ill patients. JPEN J Parenter Enteral Nutr. 1991 May-Jun;15(3):332-6.