I never knew, until I read this new research article (1), that the common IV solution used in chelation therapy contains not only EDTA but also ascorbate. It seems that the common IV cocktail contains about 3 grams EDTA and 7 grams ascorbic acid, plus enough bicarbonate to give the solution a neutral pH.
I've known for years, however, that adding EDTA to ascorbate solutions containing copper or iron ions, at neutral pH, surprisingly results in markedly enhanced oxidation of ascorbate (2)(3). So the IV cocktail contains three of the four essential ingredients/conditions (EDTA, ascorbate, neutral pH, but not metal ions). It occurred to me that, once infused into the bloodstream where the EDTA could mobilize the body's iron and copper, that this treatment would likely result in the enhanced oxidation of ascorbate to dehydroascorbic acid. It didn't take any time at all to find a report indicating this is true (4).
In a large clinical trial named TACT, chelation therapy demonstrated a significant and substantial reduction in risk for adverse cardiovascular events in diabetics (5). These beneficial results might be explained, not by the standard "toxic metals" concept generally espoused by practitioners of chelation therapy, but instead by providing large amounts of DHAA to red blood cells (and other cell types) that can only absorb vitamin C in that form.
Heart muscle cells (cardiomyocytes), like red blood cells, can only absorb vitamin C in its oxidized form (6). One report has demonstrated that DHAA but not AA is effective in cardiac sepsis (7).