Does your body excrete most of things that you eat through skin as well for example milk?

No. Very few components of the human deitary survive digestion to be secreted while perspiring. Some of the VERY few are... * Salt -- this is to maintain homeostasis * Garlic -- this isn't proven but observed * Fermented Fish --- ditto. * DMSO (Dimethylsul;foxide) -- this is used as a transdermal medium and smells like garlic. I don't understand the properties, but it's not clear how "secretion" works in this instance. So basically no -- you don't secrete food through your skin.