The article below just came out in the journal Digestive Diseases.

Even though they overemphasize the psycho-social factors, at least they acknowledge the food and antibiotic factors in IBS.

From Karger.com:

Irritable bowel syndrome (IBS) is characterised by abdominal pain and an erratic bowel habit, which depending on the definition used affects 5-10% of the population.

As a typical complex disease, it is likely that the condition will develop when a genetically susceptible individual is exposed to an appropriate environment stimulus.

This bio-psycho-social model assumes that there is no one cause of IBS, but rather that it is the product of complex interactions between host and environment.

Host factors include gender, age and psychological characteristics, while environmental factors include psychosocial stressors, gastrointestinal infections, antibiotics and food.

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Copyright © 2011 S. Karger AG, Basel.

Source
University Hospital, Queen's Medical Centre, Nottingham Digestive Diseases Centre, NIHR Biomedical Research Unit, Nottingham, UK. robin.spiller@nottingham.ac.uk
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