skin-identical ingredient

Really nice ingredients that can be found in the skin or mimic the things that can be found in the skin naturally. They have two big groups:

  1. NMFs (Natural Moisturizing Factor): things that can be found inside the keratinocytes (skin cells) and help our skin to bind water. Glycerin or hyaluronic acid are famous NMFs. They are super-duper important in keeping the skin nicely hydrated.
  2. SC (Stratum Corneum - the outer layer of the skin) Lipids: between the skin cells there is a goopy stuff called the extracellular matrix. It consists mainly of lipids and is super-duper important in having a healthy skin barrier. Ceramides, cholesterol, and fatty acids are important SC lipids.

Be it an NMF or some lipid, it's always nice to spot skin-identical ingredients on an ingredient list. :)