The oats in Clif bars are killers. There's enough cross contamination with wheat (and some suspicion of oats themselves anyway) that oats can be real trouble.
If you eliminate the bad 4: wheat, oats, barley, and rye (and all their relatives like spelt, etc.) you might want to switch to Clif Nectar bars for a while just to avoid the possibility.
Brigham and Woman's has one of the best celiac/gluten intolerance research groups out there. Great resource for you to either confirm or rule out gluten sensitivity influencing your symptoms!
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