A study found that 70% of people with IBS symptoms felt better when they cut this out of their diet.
Medically reviewed by Dr Juliet McGrattan (MBChB) and words by Jenny Cook
Around 8.5 million people living in the UK are currently following a gluten free diet. For some – around 1 per cent of people – removing gluten is necessary due to coeliac disease. However, others are cutting out a whole food group because they mistakenly think it is healthier for them, or because they believe they suffer from non-coeliac gluten sensitivity.
Never heard of it? Unlike gluten, fructan isn’t nearly as well known. Fructan is a type of carbohydrate that’s found in some wheat, fruits and vegetables – most notably onions – which, according to the study, can cause similar symptoms to those experienced with ‘gluten sensitivity’. Here’s what you need to know.
Fructan vs gluten
For the study, scientists looked at a small sample of 59 individuals who already followed a gluten free diet, despite being told they did not have coeliac disease.
They were then assigned random diets that contained either gluten, fructan or a placebo, which they had to follow for a week.
The participants’ symptoms were then measured using a gastrointestinal symptom rating scale, which was originally designed to note IBS symptoms in patients.
It was found that the fructan diet triggered 15% more bloating and a 13% increase in overall gastrointestinal symptoms, compared to the placebo alternative. Interestingly, the gluten diet had no effect. According to the study authors, this may explain why people with irritable bowels often improve on gluten free diets but don’t make a full recovery.
It was found that the fructan diet triggered 15% more bloating.
Study lead Peter Gibson, of Monash University in Australia, said: “Gluten was originally assumed to be the culprit because of coeliac disease, and the fact that people felt better when they stopped eating wheat… Now it seems like that initial assumption was wrong… Certainly the evidence points to fructans being more of a problem.”
These findings fit with previous trials, which showed that roughly 70 per cent of people with IBS feel better when they cut out fructans and other nutrients from a food group known as FODMAPs. As a result, experts often recommend low-FODMAP diets to patients with stomach issues.
70 per cent of people with IBS feel better when they cut out fructans and other FODMAPs.
Speaking to New Scientist, gastroenterologist Katie Ellard explained: “Once coeliac disease has been ruled out, I still recommend knocking off wheat to see if that helps, but I explain that it’s to eliminate fructans, not gluten, from their diet.”
As well as onions, fructan most commonly occurs in some breads, barley and many common vegetables like cabbage and broccoli. So, although more research needs to be done, this is definitely something to bear in mind when trying to get to the bottom of your tummy troubles.
Always see your GP if you are repeatedly suffering with stomach issues.