Do you really know what a skin barrier is?
You must say that the outermost layer of skin, and then? This knowledge does not guide you in skin care. What you really need to know is its essence. It consists of about 50% ceramide, 25% cholesterol, and 10-25% fatty acids.
The point is, what is ceramide?
Ceramide is a kind of amide compound formed by the dehydration of long-chain fatty acids and the amino group of sphingosine. It mainly contains ceramide phosphate choline and ceramide phosphate ethanolamine. Phospholipid is the main component of the cell membrane. 40%~50% of sebum in the stratum corneum is composed of ceramide. Ceramide is the main part of the intercellular matrix and plays an important role in maintaining water balance in the stratum corneum.
So what effect does ceramide have on your skin?
Ceramide exists in our skin itself. As a typical natural lipid, its structure and polarity are very similar to that of keratin and hair fiber, which is easily absorbed by skin and hair and can promote the penetration of other nutrients. It is often used with linolenic acid, hyaluronic acid, and vitamins for conditioning cosmetics. The amino group (sphingosine) and a carboxyl group (fatty acid) form ceramide through an amide bond. The carbon chain length, saturation, and hydroxyl number of sphingosine and fatty acid can change, so there are hundreds of ceramide. At present, there are 12 kinds of ceramide detected in human stratum corneum.
- Reduce water loss
Ceramide has a large number of hydrophilic groups and a strong affinity for water. It can be said to be a very efficient humectant. It can prevent water and electrolyte loss, which is the most basic function of ceramide. With the increase of age, the ceramide in the skin is lost, and the skin is easy to become dry. Research shows that even if only a single component of ceramide is added, it can effectively reduce skin water loss.
- Repair skin barrier
Connect the lipid matrix and keratinocytes, strengthen the barrier function of the skin, reduce harmful substances entering the skin through pores and sweat glands, and thus have the anti-sensitivity effect. Everyone should be familiar with the “brick slurry model” of the skin barrier. Keratinocytes are “bricks”, intercellular lipids are “mud”, and ceramide is an important material of “mud”. While locking in water, ceramide forms covalent bonds with proteins on the surface of keratinocytes, which closely bind cells together. It is vital to maintain a healthy skin barrier by preventing the loss of water and nutrients inside and the attack of bacteria and microorganisms outside.
- Anti-oxygen and anti-aging
The sphingosine carbon chain in ceramide has double bonds and terminal hydroxyl groups, which indicates that it is easy to oxidize and break the double bonds, so it has an antioxidant effect. Some studies have shown that low concentrations of ceramide can stimulate the proliferation of fibroblasts and inhibit the expression of matrix metalloproteinases, so ceramide has a certain anti-aging effect. Ceramide is often compounded with other effective ingredients to achieve a compound effect. Such as moisturizing ingredients (hyaluronic acid, dextran), anti-inflammatory ingredients (red myrrh alcohol, purslane extract), anti-aging ingredients (polypeptides), whitening ingredients (nicotinamide, vitamin C), etc.
Why should people supplement ceramide?
Although there is ceramide in the skin itself, it will gradually lose after the age of 25 or even earlier. In addition, factors such as sun exposure and sudden changes in temperature will continue to damage the skin and reduce the production of ceramide. When ceramide is exhausted, the skin will become dull and dry over time, and in serious cases, it may even lead to skin conditions such as psoriasis and eczema. So we need to supplement ceramide to maintain a healthy state of the skin.