skip to main content

Investigating a potential treatment for IBS


In a 2012 British Medical Journal case report, Dr Bernard Corfe, from the Molecular Gastroenterology Research Group, and medical librarian and PhD student Vicky Grant suggest that vitamin D3 may be an effective new treatment for IBS. Their findings are based in part on a novel systematic review of online patient-led accounts, which has led to the design of a clinical trial.


Irritable bowel syndrome (IBS) is a widespread chronic functional disorder of the gastrointestinal tract. It has debilitating and embarrassing symptoms, and a damaging impact on quality of life. As the cause is still not fully understood, treatment is complex, more open to complementary approaches and can vary for each individual.

Vicky has had IBS for nearly 30 years; she has tried every treatment she could find with little success. But in 2010, she came across patient forums and blogs that suggested high amounts of vitamin D3 could help. Self-administered doses of the nutrient, which has an upper safe limit but no recommended daily intake, showed that she was on to something.

Vitamin D3

In Vicky’s case, taking vitamin D3 has improved her gut function to near normal. She has also found that the vitamin alleviates seasonal affective disorder (SAD) and depression. In recent years, medical studies have investigated the role of vitamin D for several diseases and conditions, but there has been little interest in analysing the kind of anecdotal evidence found on patient-led websites.

Online reports by patients hold potential, says Vicky: “I was interested in looking at what patients were saying and finding another way of appraising the research.” She teamed up with Dr Corfe to work up a case report and take a more formal approach to the anecdotal literature, leading to a more cohesive body of work. Together they applied a systematic review process to some online patient-led literature identified by Vicky. While this was useful, it did reveal that data were broadly supportive, but inconsistent.

Future plans

To get more concrete evidence, a randomised controlled trial to test the effects of vitamin D3 on IBS is now in the final planning stages. Run over 12 weeks, the pilot trial will show who benefits from additional vitamin D3. The focus will be on if it works rather than how it works. Probiotic company Obsidian Research Ltd are sponsoring the trial, and volunteers will be recruited through the researchers’ existing networks.

Dr Corfe explains, “Using a two by three fractional factorial design – volunteers will take either a placebo, vitamin D3, or vitamin D3 and a probiotic – leads to a robust trial that considers the treatment from a nutrient rather than a medicinal perspective.”

Vicky continues to work closely with national charity the IBS Network and is collaborating with academics in the School of English for the Storying Sheffield project. Through this, she hopes to draw on patient experiences to make recommendations for self-help support groups.

The research has been featured in the Daily Mail. See IBS Network: Storying Sheffield: