Sodium Pyrrolidone Carboxylic Acid (Sodium PCA)

Sodium PCA, or sodium pyrrolidone carboxylic acid, is a very efficient humectant, being part of the skin's natural moisturizing factor. As the sodium salt of PCA is a derivative of the amino acid proline, this substance certainly has an important role to play in the hydration balance of the skin. It is naturally occurring in the skin and a "skin-identical" ingredient, meaning that it emulates the molecules already within healthy skin, making it super biocompatible.
Its main purpose is to act as an attractant and binder of moisture from the ambient environment, helping skin to retain water and be more hydrated. For such reasons, sodium PCA becomes especially effective against dryness and may prevent TEWL, one of the most important factors in skin dehydration. It holds several times its weight in water, which contributes to boosting the moisture level in skin and improving skin texture and suppleness.
Sodium PCA has a slippery feeling and is a very effective moisturizer that works well in everything from creams to serums and gels. Moreover, it increases the barrier function of the skin by supporting the layer that keeps the irritating agents of the environment outside while it locks moisture inside. The strengthening of this barrier will soothe sensitive skin and enhance resilience.
It is also non-comedogenic, it does not block pores, hence it can also be successfully used in formulations either for oily or acne-prone skin. It is sensitive enough to find application even in sensitive skin products.
It is an excellent humectant, a skin-identical ingredient, and naturally occurring; it helps the skin to retain moisture and hydration. This aid to the inbuilt skin moisture barrier enables it to retain better water for giving smoother and healthier skin, and that is why it has appeared as a useful ingredient in many moisturizing skincare products.