Most people are on the strict forum diet for 6-18 months before reintroducing foods. I have been eating chia seeds pretty much all along and haven’t had trouble, but I don’t have a lot of them, same with flax. I started those ones maybe a month or two in. I’m heading towards six months right now, fyi, with a speedy recovery, and I feel I am still not quite ready to introduce anything not on the strict diet. I was going to this month, but I think I’m going to wait until August when I’m a little bit more stable.