IBS doesn't necessarily have a food trigger for everyone, although it's common. Common things that can be eliminated include gluten, wheat, dairy, spicy food, caffeine, sweetners and some people have problems with all sorts of other things.

For me the main culprits are coffee, dairy products and alcohol.

IBS for some people is hugely influenced by emotional state/mood, and when they are feeling more emotional the symptoms will get worse.

My experience and from what I've heard from others is that you can go from constipation to diarrhoea within days, pain and bloating is common as is gas and generally feeling uncomfortable/queasy. Sometimes I also feel nauseated.

IBS is not a disease or anything like that, it is a collection of symptoms- hence the syndrome part of the name.