Magnesium, as an electrolyte mineral, aids in skin hydration and barrier repair. It also affects how skin cells migrate through the skin's surface layers, shed, and react to external stimuli.

Pure magnesium and some types of magnesium, such as magnesium chloride, are not great at penetrating the skin; however, combining magnesium with PCA or lactic acid (as in magnesium lactate) helps to resolve this problem and more beneficial to the skin.