I would like to share some information with you as I just found out that I was reacting to hydroxypropyl methylcellulose (HPMC) or Hypromellose, E464, which is used as an additive as an emulsifier, thickening and suspending agent and an alternative to animal gelatin. It is used an a substitute for gluten in GF bread, for instance.
My symptoms were waking through the night and lower back muscle pain. It was in my Magnesium/Calcium tablets.
If you are already doing ED for gluten, wheat, food additives, etc and still not feeling right. This might be what you should look out for. HTH