A laboratory study has found that ferulic acid, a polyphenol found in rice bran and other grains, can reduce contractions in isolated intestinal smooth muscle. The finding is mechanistically interesting, but it is not evidence that eating rice bran or taking ferulic-acid supplements treats irritable bowel syndrome.
Researchers at Toho University tested ferulic acid in guinea-pig ileal smooth muscle and reported that it suppressed contractions triggered by several signalling molecules. Their experiments suggested that the effect was linked mainly to reduced calcium entry through voltage-dependent calcium channels.
That mechanism could be relevant to disorders in which intestinal motility is altered, but several steps separate an isolated-tissue experiment from a clinical treatment. The study did not demonstrate symptom improvement in people with IBS, establish an effective oral dose or show that ordinary dietary intake produces the same concentrations in intestinal tissue.
The direction of effect also matters. Suppressing intestinal contraction could theoretically be unhelpful in conditions characterised by slow transit or constipation. For that reason, the findings should be viewed as early pharmacological evidence rather than dietary advice.
The university’s research summary is available from Toho University. Further human research would be needed before drawing conclusions about prevention or treatment.
