Irritable bowel syndrome (IBS) affects 10-15% of people around the world. It is a chronic gastrointestinal disorder with symptoms including abdominal pain, discomfort, diarrhoea and constipation. Most medications are used to treat these symptoms independently of each other and few treatments relieve the symptoms of IBS as a whole (Drossman et al. 2010). Studies have demonstrated that there is a substantial, clinically significant placebo effect for IBS. This then led Harvard researchers to investigate if using placebo for IBS could be both ethical and effective.