Dairy and breastfeeding

Has anyone tried giving up dairy while breastfeeding? My LO is gassy all the time which makes her fussy. We have been using gripe water to help get the burps out but I am starting to wonder if dairy is causing some of her gassiness. It seems like it is worse if I eat a lot of cheese, ice cream, and milk, etc. The other day she drank 1 ounce and was crying so much I burped for 50 mins. And got 5 burps but she was still crying. I think some of those were still stuck from the last feeding. Also, as I consider giving up dairy, I am discovering how much stuff has dairy in it!