both my kids and myself have gluten intolerance. we still have a very active life. We just pack food along. if going somewhere else we bring a dish to share. It works. It doesn’t have to be restrictive once you get the hang of it. We have some friends that are supportive and if we go to their house they try to accomodate us as well. Classes and outings, i send the kids with food. So they still have “something” but is not what the other kids are having.
I knew my daughter was intolerant from the time she was under a month old. I could tell by her reactions to milk when she was nursing and that she was getting sick. my son we didn’t get it figured out until he was 7.