Although it is the only non-living layer of our epidermis, the skin’s stratum corneum (SC) has the critical job of providing a shield from the outside world. The SC is made up of three vital components: the corneocytes, or dead skin cells; the lipid bilayer; and a combination of lactic acid, urea, salts and amino acids that is collectively referred to as the skin’s natural moisturizing factor (NMF). When functioning properly, the lipids act like plastic wrap that surrounds the corneocytes, sealing in the NMF and keeping this outermost barrier healthy and hydrated. Unfortunately, this barrier system is relatively easy to disrupt, leading to transepidermal water loss (TEWL), or the evaporation of our NMF.
The terms TEWL, impaired barrier function and skin dryness are often used interchangeably. When TEWL occurs, several essential functions, including desquamation, are not possible. This often instigates or worsens skin conditions. The most obvious characteristics of impaired barrier and TEWL is dry, flaky skin; however, a dull complexion may also be an indicator.
The best and most comprehensive way to improve and protect skin suffering from barrier issues is to use products that include both humectants (ingredients that draw moisture into the epidermis from the dermis) and occlusives (ingredients that trap moisture within the epidermis). One well-known occlusive is petrolatum. Think old fashioned petroleum jelly. Yes, it is effective as it traps 99% of moisture within the skin, but its greasy and heavy feel makes it an unpleasant option for facial use. Silicones like dimethicone and cyclomethicone are better options as they have a light cosmetically elegant feel, but their moisture-trapping action and powdery finish are their only benefits. This leads us to niacinamide.
People sometime mistakenly equate niacin and niacinamide. Although they are related members of the vitamin B family, they have different actions. Niacin, or nicotinic acid, is converted into nicotinamide in the body. This conversion process is actually what causes the infamous flushing that occurs from topical and internal niacin use. When used topically, niacinamide does not need to convert an therefore does not cause the negative vascular responses of topical niacin. Additionally, niacinamide has been shown to increase the skin’s important essential free fatty acids, ceramics and cholesterol, further improving dry skin.
To learn more about PCA SKIN products and ingredients, please call 877-722-7546.