Re: Shelly - One more question :-)

Bieler broth has to be homemade, there's no commercial producer of it yet. There's a recipe link in the Broth's post, and the recipe is all over the 'net. It's quite famous.

The manufacturers of colosan and Oxypowder both say the magnesium is not absorbed all that much. I have my doubts, suffice to say that you shouldn't take it for more than 2 weeks if your kidneys are an issue, because it simply isn't worth the risk, especially when you have other alternatives. If you have healthy kidneys there's no reason to be concerned, just be conservative - use them for no more than 4 weeks and don't take any other magnesium supplementation at that time.