Thanks. I Am Writing In Behalf Of My 35 Year

Thanks. I am writing in behalf of my 35 year old son. He has always had sleeping issues and has a delicate stomach. I read recently there is a blood test that an internist can give that would indicate some sort of deficiency that might cause both conditions. Of course, I can not find the article and can not recall the name of said deficiency. Is this too vague? I promised to ask. Thanks so much, Mary