Effects of linseeds on the symptoms of irritable bowel syndrome: a pilot randomised controlled trial

Background: Manipulation of dietary fibre intake represents a longstanding treatment for patients with irritable bowel syndrome (IBS), particularly for those with constipation. Linseeds are often recommended by both clinicians and dietitians as a source of dietary fibre to alleviate symptoms. Recent guidance on the management of irritable bowel syndrome (IBS) advises that linseeds may reduce wind and bloating, although there is limited clinical evidence to support this recommendation. The present pilot study aimed to compare the clinical effectiveness of: (i) whole linseeds versus ground linseeds; (ii) whole linseeds versus no linseeds; and (iii) ground linseeds versus no linseeds in the management of IBS symptoms. Methods: In an open randomised controlled trial, subjects with IBS (n = 40) were allocated to one of three intervention groups: two tablespoons of whole linseeds per day (n = 14), two tablespoons of ground linseeds per day (n = 13) and no linseeds as controls (n = 13). Symptom severity (primary outcome) and bowel habit were assessed before and after a 4-week intervention and statistical differences between the groups were compared. Results: Thirty-one subjects completed the present study. Between-group analysis comparing the improvement in symptom severity did not reach statistical significance for whole linseeds (n = 11) versus ground linseeds (n = 11; P = 0.62), whole linseeds versus controls (n = 9; P = 0.12) and ground linseeds versus controls (P = 0.10). There were no significant changes in stool frequency or stool consistency for any of the groups. Conclusions: Linseeds may be useful in relief of IBS symptoms. Further research is needed to detect clear differences between the effects of whole and ground linseeds.