Many patients with irritable bowel syndrome (IBS) are disillusioned by the lack of efficacy of treatments and suffer from numerous symptoms not covered by the Rome criteria for IBS, as the current empirical treatment regimens fail to address these persistent debilitating 'IBS associated symptoms'. These symptoms are similar to other symptom complexes like chronic fatigue and the so-called 'candida syndrome', and many seek help from alternative medicine. The possible role of Candida and yeasts in non-immune compromised individuals is disputed and is the subject of this review. Even if the involvement of yeasts in the aetiology of IBS still remains unclear, there is increasing evidence for yeasts being able to cause IBS-symptoms in sensitized patients via Candida products, antigens and cross-antigens. But more research is needed before antifungal treatment can be recommended as a first line treatment for IBS.