I didn't put this in dental because she has excellent dental hygiene and I can tell it has nothing to do with that. She eats healthy, she is otherwise healthy. This started when she was around two or so and she's 11 now. I feel so bad for her and want to help her. What can I do?
Might not be gut, might be saliva production or the lack of it. My brother was finally diagnosed around age 14 http://en.wikipedia.org/wiki/Sj%C3%B6gren's_syndrome. Its not that uncommon, and for him, we noticed the bad breath starting around age 2. Otherwise, he is perfectly healthy with no other autoimmune symptoms. He manages the bad breath by sipping water frequently and chewing gum.
Well that and chewing gum to try to stimulate the saliva production, which keeps the mouth cleaned out better.