Natural moisturizing factor in human skin. Keep skin fresh and hydrated for face and body. Non-oily. Non-comedogenic. Hypo-allergenic. Paraben free. TwinLab Na-PCA is a PH-balanced, concentrated solution of the sodium salt of pyrrolidone carboxylic acid, a natural moisturizing factor found in human skin. Na-PCA is synthesized from glutamic acid, a nonessential amino acid. The skin contains natural moisturizers, the most important being Na-PCA. Old skin contains only about half the amount of Na-PCA as that found in young skin. The ability of skin to hold moisture is related to its Na-PCA content. It is water, and not oil, that keeps skin soft and supple. Na-PCA helps keep skin moisturized, improving its appearance and giving it a moist and youthful glow. Since it will not clog pores, you can feel comfortable using this natural moisture source in many ways to keep your skin fresh and hydrated: Use to moisturized under make-up or skin cream; Keep spray in refrigerator to refresh and cool down on summer days.