The present study investigated the diet and quality of life of irritable bowel syndrome (IBS) patients in comparison to the background population. Furthermore, it studied the effects of guidance on diet management on changes in food intake, quality of life and symptoms. A total of 35 healthy controls, 36 IBS patients and 43 IBS patients who had received guidance on diet management 2 years earlier were included. The controls and patients were asked to complete an FFQ questionnaire, an SF-NDI questionnaire, an IBS-QoL questionnaire and a Birmingham IBS symptom score questionnaire. There were no statistical differences in the intake of calories, carbohydrates, proteins and fat between the controls and IBS patients, with or without guidance on diet management. IBS patients made a conscious choice to avoid certain food items, some of which belong to fermentable oligosaccharides, disaccharides, monosacharides and polyols (FODMAPs). They had a higher consumption, however, of other food items that are rich in FODMAPs. They also avoided other food sources which are crucial for their health. Two years after receiving guidance on diet management, IBS patients had a different diet profile. They avoided all FODMAP‑rich food, consumed more food with probiotic supplements and did not avoid food sources that were crucial to their health. In addition, they had improved quality of life and reduced symptoms. Although at first sight the diet of IBS patients did not differ from that of the background population, detailed examination showed avoidance of certain food items. Guidance on the management of diet improved their choice of a healthier diet, improved quality of life and reduced IBS symptoms.
Keywords: diet; irritable bowel syndrome; quality of life; probiotics; symptoms.