It's one of those things that is hard to differentiate, unless you eliminate one to see if it makes a difference. But After coffee- it could be due to the coffee cos it is a stimulant and so therefore stimulates the bowel. As for milk drink depends also what the drink contains, as it could be containing something that does it. DH used to get severe diarrhoea after drinking milk/milk products- so he had lactose free milk (which basically contains the lactase enzyme) (you can also buy this in tablet form). Anyway it must have rebuillt up the enzymes in his stomach because now he doesn't have a problem. Ok so that probably wasn't very helpful.