Dietary interventions for irritable bowel syndrome
Research type
Research Study
Full title
Dietary restriction of fermentable carbohydrates (FODMAPs) in conjunction with prebiotic supplementation in irritable bowel syndrome: studies of microbiological and symptomatic outcomes
IRAS ID
171205
Contact name
Kevin Whelan
Contact email
Clinicaltrials.gov Identifier
REC referance number, 15/WA/0119
Duration of Study in the UK
2 years, 0 months, 2 days
Research summary
Irritable bowel syndrome (IBS) is a chronic and relapsing disorder of the gastrointestinal tract characterised by the
presence of abdominal pain or discomfort which may be relieved by defaecation. Other symptoms may include
abdominal distension and wind. IBS affects about 12% of the UK population. A diet low in fermentable carbohydrates
may improve symptoms in those suffering with IBS. This is because these carbohydrates result in fermentation and
fluid shifts that can trigger bowel symptoms. Although it is recognised this diet works in clinical practice, it has never
been compared to a control or placebo diet. Using a 'sham' diet is one way to do this. A 'sham' diet is specially devised
to look like a proper diet but doesn't affect what you are trying to measure in the treatment diet. The effect of the diet on
nutrient intake and quality of life has also not been researched carefully.Some of these fermentable carbohydrates are known to trigger IBS symptoms are also ‘prebiotic’. This means they
have positive effects on the bacterial profile (microbiota) in the colon or bowel. Our recent study showed that a
fermentable carbohydrate restriction leads to a reduction in bifidobacteria. One way to modify the bacteria is to use
prebiotic food supplements. It is unknown whether adding a prebiotic food supplement to the diet can help maintain
bifidobacteria at normal levels while following this diet. We propose a prospective randomized controlled trial to
investigate this. Sixty-nine patients with IBS will be recruited. Baseline data on faecal microbiota, gut
behaviour, diet and quality of life will be obtained. Patients will be randomised to one of 3 groups: intervention diet +
prebiotic food supplement, intervention diet + placebo,sham diet + placebo.
The same variables will be assessed again at week 4.REC name
Wales REC 4
REC reference
15/WA/0119
Date of REC Opinion
30 Apr 2015
REC opinion
Further Information Favourable Opinion