J.W.
A thing to consider is you child could have Sensory Integration where he could be under or over sensitized. People who are sensory integrated are ones who may hate the texture of a food so they will not eat it. My niece has this condition and it included be overly sensitive to the way her clothes felt on her, how her shoes felt, and she has also been diagnosed with ocd. My sister took her to a homopathic doctor who tested her blood and found out she was deficient in some minerals. Since she has started treatment she has improved significantly. This can be an expensive remedy, and not one many mainstream doctors believe in, but you can definitely research it. I have attended several training classes on it for my preschool I work at. Feel free to contact me if you want more information.