You can apply it topically - look for magnesium oil sprays, these are usually just concentrated magnesium chloride. Works well too, gets absorbed systemically totally bypassing digestion, only side effect is oily skin.
Reportedly, excess amounts over what the body can handle wouldn't get topically absorbed (unlike orally) and leave a white residue and that's how you'd know you've had enough - but I never had that happen to me personally.
Reportedly, excess amounts over what the body can handle wouldn't get topically absorbed (unlike orally) and leave a white residue and that's how you'd know you've had enough - but I never had that happen to me personally.