 These forms of magnesium are poorly absorbed, and in fact, some of them have laxative effects and cause diarrhea. Some people say, oh, I can't take magnesium, I get diarrhea. Well, you're just taking the wrong one. And doctors routinely prescribe the wrong one, because they don't know the difference. Magnesium glycinate, chelate, is bound to an amino acid, very, very well absorbed.