I wish I had an easy answer. Liver damage is really scary. Have you read about candida at all? There is a book I am reading currently called The Body Ecology Diet and it does talk about supporting the liver, etc. which might help you tweak the diet and understand what is happening or why. Just a thought.
I would try to avoid public eating as much as possible. If he is in school, he should be supervised to not eat any birthday party treats, others' snacks or lunches, etc. and you should send lunch, snack, and treats for him from home. Hard as it may be, birthday parties should either be avoided or you should attend with him and bring something similar for him to eat along with his peers.
There are websites to find gluten-free restaurants like glutenfreeregistry.org, and calling ahead of time and talking to the chef is very helpful, and most are very willing to accommodate special diets. We reserve eating out for special occasions, though sometimes you can find a small restaurant that is willing to work with you, especially if you become "regulars." We love Honey Cafe in Glen Ellyn for this (they have cupcakes too!)
Baking things ahead of time and freezing them for b-day parties, class parties, etc. is a great idea. There are lots of websites and blogs out there geared toward specialized diets- since there are more and more kids with allergies, etc. Try googling for GAPS, SCD, Body Ecology (BED) Diet, etc. and you will come up with a lot of great copy-cat recipes. Some will taste great and some will not- but don't get discouraged.
We have been gluten-free, sugar-free, pasteurized-dairy free, yeast-free, organic... oh the list goes on and on... for a year now. It has not been easy, but I have managed to learn to make cupcakes and fudge and ice-cream and all those things kids want to eat to feel normal (and me too!) and still taste good. I'm not a chef, but I do love to cook. We don't do sticker charts- it's just non-negotiable for my kids' health. I hope that doesn't come across as sounding uppity- that is not what I mean- what I mean is that he should not even have the option to "cheat."
I have a blog where I blog about new recipes that I make that my kids like. I am always up for a challenge to create things for kids with special diets too- so feel free to message me or comment and I will do my best if there is something he reallllly misses, to create a copy-cat for you.
I hope you can get him healthy. I know it's really frustrating.
Hugs,
M.
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