Good question. I know high levels of heavy metals in your blood can be chelated filtering these out in a lab. I do doubt insurance would cover it for GD since there has been no medical testing as to the benefits of chelation with GD. There has been proof heavy metals are tied to Parkinson's and Alzheimer's so wonder if they allow it for those conditions.
I also wonder if the reason I was so successful chelating my blood with cilantro to put my GD in remission is because I learned 2 years ago I am allergic to 5 different metals from a blood test before I considered getting an implant with metals. Perhaps for some of us, even low levels of metals in our bodies causes excess inflammation for elevated histamines.
The trouble with getting funding for causes of GD is that GD doesn't kill us, although at times it may make us with we were dead. The medical profession can't feel our misery.