Kid not eating

Jordan

So I have almost a three year old and he is the pickiest eater ever. When he was born he had bad eczema which actually turned out to be allergies. He sees a pedi and a dietitian and he still will not eat. I have tried smoothies, allergies alternatives and he still won't eat! He does drink soy but how can I get him to eat what else can I do I literally give up. Like he won't eat dinner ever he won't barely eat breakfast or lunch and he doesn't even like snacking. I don't know what to do they said it's normal but how can it be