When you do the elimination thing, you only get rid of one family of agents at a time.
Gluten free is not that hard, you end up with fresh eating every day. I did it for 3 yrs...but I did miss bread and pizza! It turned out for me that gluten wasn't really the culprit.
So you don't have to get rid of dairy, right away. But I would keep a food diary to see if things cluster. MSG can sneak up on you that way and you can then see it when you write it down.
If all your autoimmune panels were normal, I'd think this is allergic. Viral and allergic seem to be the most common in all over skin burning. Your previous reaction to Niacin therapy is also a big clue.
Do antihistamines help? That would be a clue to allergy.
All over itching can be from liver/gall bladder issues too. It is a sign of gall bladder malfunction.
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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