Dietary fibre and the irritable bowel syndrome.

The dietary fibre intake of 25 patients with the irritable bowel syndrome was assessed by dietary recall over one week for the period before onset of symptoms, at diagnosis and after six months treatment with bran and a fibre-rich diet, and compared with controls matched for age and sex. Mean intake of patients fell from 20.2 g per day before onset of symptoms to 17.8 g at diagnosis (n.s.), when it was significantly less than the controls' intake of 22.6 g (P less than 0.01). The 20 patients who improved with treatment increased their intake from 18.9 g to 24.8 g (P less than 0.02); the five patients who did not improve did not increase their intake significantly (13.5 g to 15.6 g).