Board Thread:Lore Discussion/@comment-107.1.228.86-20130703034053/@comment-9212235-20170721210308

Magicka is Aetherial energy, also known as creatia. It is definitely absorbed through the skin. Think of it like vitimin D. However, most of it likely comes from eating food.

This is also theorized to be why vampires must drink blood. Not only are they unable to absorb magicka, but it hurts them. They must obtain magicka through blood sucking. All things require magicka to live.