We went through this with the worst of teething we dealt with so far (which was first molars and the first 2 canines so far). She stopped as soon as they were all in. She would reject her favorite foods, spit, throw, etc. after never having a problem before. Sometimes new utensils would be a good distraction and help her eat but it was a wait it out game for us for the most part.
@JL I'm really starting to think it's his teeth. He's getting canines on the bottom (idk what those are called) lol but otherwise all other teeth are through except 2nd molars. I've been watching him though and even when his mouth is empty he does this weird chew on the side of his mouth. Oooof I hope we don't have to wait it out real long.
I have no advice as I am going through this right now. My son used to eat pretty good and would eat a range of vegetables, rice, pasta, and fruit. But lately he’s only been interested in snacks which is not healthy if he’s only eating snacks all the time. One mom gave me a tip that try mixing snacks and healthy food together for example, try dipping chips into guacamole with peas. The key might be to get creative and hide the good stuff in the not so good stuff.