It was late in 1962 when I had my first obvious attack of the condition known as IBS or irritable bowel syndrome. It was, indeed, the day of my first Leaving Certificate Examination and I developed acute diarrhea. A great deal was expected of me as I had been an excellent student, and the pressure proved too much! I don’t remember exactly what I took to try to relieve my symptoms but ‘glucose powder’ was certainly something that helped me and I did make it to the exam room though I felt shaken and light-headed. The same problem affected me every day of the exams and not surprisingly my results were not to my expected standard.
I think that my experience strongly supports the idea that there is usually a nervous/emotional component to this health condition, but our family history suggests that the underlying cause is inherited. Nothing was known about IBS in 1962, and I think we are still at the early stages of understanding several chronic gut issues. Fortunately, in the 62 years since then, a research group from Monash University has developed an App that helps people like me select foods that won’t upset our delicate guts, but we still have much to learn. Most weeks I still get ‘something’ wrong!
There has been relatively little ‘helpful’ research published on IBS but in 2000, Goldstein et al published a paper ‘Carbohydrate malabsorption and the effect of dietary restriction on symptoms of irritable bowel syndrome and functional bowel complaints’. In their cohort of 239 patients, 94 met the Rome criteria for IBS and the second group of 145 were defined as having ‘functional complaints’. The sugars tested were Lactose, Fructose and a mixture of Fructose and Sorbitol. The study reported that only 7% of the IBS group and 8% of the second group absorbed all sugars normally. 61% of the subjects in each group had problems with absorption of both Lactose and Fructose/Sorbitol. Lactose malabsorption was 78% in both patient groups.
Fortunately, 56% of IBS and 60% of the second group were markedly improved by removing all those sugars from their diets.
Although Lactose is a common sugar, its absorption follows different ‘life’ rules to the other sugars. When we are babies, we need lactose to digest our mother’s milk. But many of us lose the ability to absorb lactose as we mature. In general, people from Southeast Asia and East Asia lose the ability at about age 6 whereas many people of other ethnicities retain the ability for life. Sometimes the ability can be lost for some time after a bout of gastroenteritis and then return, but many people lose the ability as we age. Depending on your tolerance, you may be able to eat some cheese but not be able to drink milk. Fortunately, most of us can now purchase lactose-free milk and yoghurt or foods called ‘milk’ or ‘yoghurt’ that are made from products like almond, soy or coconut, so lactose intolerance need not be an issue.
The other sugars are more difficult. Despite taking great care of the food we prepare ourselves, those of us who have sugar intolerances can easily be ‘tricked’ into consuming fructose, fructans and sorbitol. Fructans are long-chained sugars, and these are converted into fructose in the large intestine. This means that if you are sensitive to fructose and fructans, eating fructose (say ‘an apple) will give you bloating almost immediately whereas fructans will move through your digestive system and give you bloating, pain and (usually) diarrhea twelve or so hours later. You can’t easily ‘fix’ the fructan problem, but you may be able to reduce the ‘fructose effect’ by adding glucose because it’s the ratio of fructose to glucose in the foods that causes the reaction. That is – if the culprit is only fructose but other sugars may well be present.
Sorbitol is a type of carbohydrate that falls into a category of sugar alcohols called polyols. It’s found in high amounts in some fruits such as blackberries, cherries, plums, pears, and apples and is also commercially manufactured to preserve moisture and add sweetness to many foods. It is especially common in many sugar-free ‘treats’ such as gum, mints and candy, so these so-called ‘treats’ can make many people sick. Possibly ‘worst of all’, Sorbitol is the starting material for pharmaceutical compounds like sorbose and ascorbic acid and is frequently used as a vehicle for suspending drugs. Imagine how frustrated I was when (unusually for me) I needed a cough medicine and discovered that all the cough medicines that were available contained ‘sorbitol’.
So, those of us who are affected by sugars must read all the labels (no matter how tiny the print) and learn that words like sweetener probably mean sorbitol. The only people who are likely to benefit from the ‘sorbitol obsession’ are people who suffer from constipation. At least it helps them!
References:
R Goldstein 1, D Braverman, H Stankiewicz
Carbohydrate malabsorption and the effect of dietary restriction on symptoms of irritable bowel syndrome and functional bowel complaints
Isr Med Assoc J 2000 Aug;2(8):583-7