The Eades love magnesium as a supplement, they consider our low Mg intake to be a major deviation from the evolutionary milieu (our drinking water has the mineral removed.) They devote an entire chapter of Protein Power to it ("The Magnesium Miracle".) For example, Dr. Mike writes:
"Magnesium is just about our favorite supplement. In fact, if we just had one supplement to recommend, and no other, it would be magnesium."
Most other paleo bloggers haven't put much emphasis on magnesium. So, how important is magnesium? Should we be supplementing (to restore biological normality), or is there enough in food?
As an agronomist, I am pretty concerned with the lack of minerals in our nation's depleted soil. Are supplements paleo? Probably not, but neither is water fluoridation and topsoil depletion. Unfortunately we can't change these as easily as our eating habits.
I imagine a better world where magnesium was added to our drinking water supply instead of fluoride. That said, I've included magnesium in my paleo lifestyle for years on the Eades's recommendation. Since that time, I've only seen positive data associated with it.
P.s. I'm happy that my local water isn't fluoridated!
I also take magnesium per the Eades's compelling discussion and recommendation -- that's in the Protein Power Lifeplan book if anyone wants to read it. (I have an R.O. filter on my water tap to remove the nasty fluoride). The great thing is that it also helps in, er, keeping things moving better than anything else I've tried, so there's a real practical benefit. :)
I also think water is a relatively poor source. Good food sources include dark green vegetables (Mg is at the center of the chlorophyll molecule in plants, in the same way iron is at the center of hemoglobin in animals).
I believe I've heard it activates something like 300 enzymes in your body for starters, but yeah there's all kinds of interesting studies on us being deficient and what it can do for you. So far just taking ZMA (which includes more than a recommended dosage of MG in a form more easily used by your body than the MG ocide in most low quality multis) nightly is doing wonders for me in both sleep and everything affected by my sleep quality (which really is pretty much everything).