Laura, I can't count how many or how much money we've spent on supplements, I could probably stock a store with what we've tried! At the end of the day, though, we can only swallow so many pills. And, as Dr. Wahls said, it is far, far better to get what you need from food than from a pill, because of the syngergistic components we dont' even know about. So...
We take a multivitamin daily (if we remember, but mostly we do), it's high quality and we alternate between brands. Twice a week, we take HALF of a multimineral. Why? Minerals can build up in the body, and that can be dangerous. Magnesium is critical, as you pointed out, but you want to take the right formulation (MrsD is invaluable on these matters
) and so sometimes we take MagnaCalm which is a powder you mix into water, it's a bit bubbly, so you can put it in a juice if you like. It is much cheaper than the individual packets you can buy, fyi. I personally feel that you get more benefit from epsom salt baths, though, because your skin will absorb the magnesium while you soak in a hot bath. I sneak it into the kids' baths sometimes when they are not looking
We take extra vitamin C for the hell of it. It can't hurt and if you take buffered, it's easier on the stomach. You can get C from cranberry juice which we drink a lot of (helps with potential UTI as well, we drink the pure kind that is tart beyond words, a direct extract, not from concentrate type, but you just need a little, and couldn't get down much more than that anyway it's so tart), citrus fruits and broccoli family veggies (bonus: fiber) and then Vitamin C in a pill if you just want more.
I know our bodies flutuate from morning to night and back, in terms of probably just about everything: glucose levels, cortisol, temperature, etc. Besides our circadian rhythm, we have our constant effort at homeostasis, and that is all way over my head...so my layman's thinking is: why not give our cells what they need to make their many jobs as easy as possible? And that's where Dr. Wahls comes in, but I've sung her praises here enough