You should still be careful of western food in china. One of the problems with it is they don't really know how to handle it and prepare it in a safe and hygienic way. You should be Particularly careful eating things like dairy products that can really hit your stomach hard. I can think of two occasions where I got a dodgy stomach from eating at western restaurants both of which had a cream content to them. Just walking into a corner shop in china you'll notice a large number of products are past there use by date. My guess is restaurants sometimes operate to similar standards.