Correction
We updated our FAQ reviewing the relationship between dietary fiber and IBS. Some soluble fibers, like fructans and galactooligosaccharides, can increase symptoms of IBS. However, psyllium (a different type of soluble fiber) has been linked to reduced symptoms of IBS. We previously stated that insoluble fiber could improve symptoms of IBS. After reviewing the literature we removed this statement. Insoluble fiber, particularly wheat bran, seems to have no meaningful effect on IBS symptoms.