Dietary advice tips
(3) Irritable bowel syndrome
Irritable bowel syndrome is a motility disorder of unknown origin, in which no evidence of disease can be seen when the colon is examined. Factors implicated include previous gastrointestinal infection, stress, psychosomatic disorders, food intolerance and low fibre intake. Symptoms include abdominal pain, altered stool frequency and bloating or abdominal distension. The effects of dietary treatment are hard to evaluate because of the placebo effect and the fact that symptoms of the condition tend to be vague and non-specific. However the following factors should be considered:
- Dietary fibre intake - Traditional advice was to avoid high fibre foods because of a supposed irritant effect. However, high fibre diets now tend to be advocated, although it should be emphasised that sufferers vary enormously in their response to dietary fibre. It seems likely that patients whose symptoms are predominantly abdominal pain and constipation could benefit from an increased fibre intake, whereas those who suffer from diarrhoea may be less likely to benefit. If fibre is increased, this should be done gradually. Excessive amounts of fibre, especially bran, can make symptoms worse.
- Food intolerance - Food intolerance may be a factor in some patients and dietary manipulation may help to identify possible causes. Common culprits include wheat, corn, oats, milk and dairy products, citrus fruit, onions, coffee and eggs. In patients with food intolerance, four or more foods may be implicated, and large quantities of these foods may need to be consumed over a prolonged period of time to identify what may well be a slow reaction to a large volume of food. Identification of possible food intolerances may take up to three months and therefore demands time and commitment from the patient.
This series of "dietary advice tips" is intended to be a reminder of the main points to be made by pharmacists when giving nutritional information to the public. The conditions included in the series are those where diet is a well recognised risk factor, those in which diet contributes to the management of the condition, and others for which patients may welcome sound dietary advice.The series is written by Dr Pamela Mason (a pharmacist with a postgraduate qualification in nutrition)
