In the UK we have been selling chelated calcium since 1994. Our primary market has been the improvement of brain function and behaviour for equestrians sports like dressage, eventing, showing, jumping and trail riding.
There is absolutely no scientific study that we can find on how chelated calcium works in any animal or human. What we do know is that it isn't a simple calcium supplement because we developed the technology on horses grazing high calcium soils. We also know that when we supplemented chelated calcium and "ordinary calcium" in the same trials the horses responded completely differently.
So in 2011 we ran our first blood trials to try to better understand what was going on. These confirmed that the ionised blood calcium of horses was more likely to drop than increase when supplemented with chelated calcium. There isn't space here to describe those trials but here is a video where they are described in some detail. We have done quite a few trials in the UK and Australia since.
Our conclusion is that chelated calcium is a nutrient in its own right that seems to assist cells all over the body and part of that involves improving calcium management. It is also frequently deficient in diets whether the horse is grazing low or high calcium pastures or even low or high oxalate pastures (all of our UK sales are to horses on low oxalate diets and it helps these horses enormously). But with no independent academic studies we have to rely entirely on our own investigations. See the "Missing Link" articles for most detail.
The links below take you to some articles discussing chelated calcium. We hope you will find them of interest.