Soluble fibre may ease IBS

New research supports the use of soluble fibre as an effective treatment for irritable bowel syndrome.

Insoluble fibre such as bran, on the other hand, may worsen symptoms, say Dr Rene Bijkerk and colleagues at University Medical Center Utrecht, the Netherlands.

The researchers explain that irritable bowel syndrome is a common disorder which causes abdominal pain or discomfort alongside an altered bowel habit.

They examined the benefits of prescribing soluble fibre (10g of psyllium husks) or insoluble fibre (10g of bran) in 275 adult patients with irritable bowel syndrome.

Patients took one of the fibre treatments or placebo (10g of rice flour) for 12 weeks, during which they rated their symptoms. Success was defined as "adequate symptom relief during at least two weeks in the previous month, analysed after one, two, and three months of treatment".

Results appear on the website of the British Medical Journal. More participants on psyllium (64 per cent) completed the treatment than bran (56 per cent) or placebo (60 per cent).

The proportion of so-called responders was significantly higher in the psyllium group than placebo during the first and second months. Bran was only more effective than placebo in the third month.

"After three months of treatment, symptom severity in the psyllium group was reduced by 90 points, compared with 49 points in the placebo group," they report. Bran was not significantly more effective than placebo. Quality of life scores were similar for all groups.

The team concludes: "Psyllium offers benefits in patients with irritable bowel syndrome in primary care. Bran may worsen symptoms of irritable bowel syndrome, especially at the beginning of treatment, and should be advised only with caution."

Bijkerk, C. J. et al. Soluble or insoluble fibre in irritable bowel syndrome in primary care? Randomised placebo controlled trial. The British Medical Journal, 2009;339:b3154.