"That's the real bottleneck," says Chiang Hsing-shih. Humans have obstructing walls between the layers of the skin. These keep out viruses or bacteria, and it is all the more difficult for skin care products and make-up to be absorbed.
「這正是瓶頸所在」，皮膚科醫師姜興世指出，人類的皮膚有層障壁，像病毒、細菌等微生物都不容易進去，更何況是化妝品、保養品。