Skin Aging and Wrinkles
How the skin ages and wrinkles is a very complicated process that involves an almost limitless range of physiological occurrences. There isn't any one cause that can be addressed with a cosmetic to erase or minimize the inevitable, because the "aging" process itself is so complex and intricate. Skin, all by itself, ages in many identifiable ways. Adding one plant extract or a vitamin to the skin won't address what is needed to deal with the myriad issues for slowing down the aging process. A series of extrinsic factors (environmentally induced, such as sun damage, pollution, free-radical damage, smoking) and intrinsic factors (genetically induced, such as genetically predetermined cell cessation, chronological aging, hormone depletion, immune suppression) all culminate in what we define as aged skin.
It isn't just oxygen depletion, free-radical damage, collagen destruction, reduced cell turnover, abnormal cell formation, decreased fat content, intercellular deficiency, genetically predetermined cell shutdown, hormone loss, and so on, that affect the way skin ages--it is a combination of all these things and more taking place.
Looking at the issue objectively can help us better understand what is happening to our skin and what can and can't be done for it. Gaining insight into why wrinkle products make the claims they do and why it is most unlikely that they can actually live up to those claims will ultimately benefit our skin and our budgets, too. For example, while we know that collagen and elastin, the support structures of the skin, break down and flatten as a result of repeated sun exposure, they also become less pliant and more hardened with age, so the skin becomes less elastic. Some products claim to only build collagen or only improve elastin. That is much like building a house with only cross beams and no support beams. One without the other is useless because the house won't stay erect without both of them.
It would take an entire book to evaluate every element of the skin affected by intrinsic and extrinsic age factors, but it is important to get a basic sense of what is taking place to better understand why most antiaging or antiwrinkle creams can't possibly live up to their claims.
For example, one notable characteristic of older skin versus younger skin is that younger skin has more fat cells in the dermis than older skin. That is one reason older skin looks more transparent and thinner than younger skin and why someone 30 pounds or more overweight tends to have fewer wrinkles. Furthermore, for some unknown reason, the skin keeps growing and expanding as we age, despite the fact that the supporting fat tissues of the lower layers of skin are decreasing. That is why the skin begins to sag: Too much skin is being produced, but there aren't enough bones (remember, bone also deteriorates with age) and fat to shore it up. Simultaneously, the facial muscles lose their shape and firmness, giving the face a drooping appearance.
Certain components of the skin also become depleted with age. The water-retaining and texture-enhancing elements in the intercellular structure such as ceramides, hyaluronic acids, polysaccharides, glycerin, and many others are exhausted and not replenished. The skin's support structures, collagen and elastin, deteriorate or are damaged. Older skin is also more subject to allergic reactions, sensitivities, and irritation than younger skin due to a weakening immune system.
On a deeper molecular level, the DNA and RNA genetic messages to the skin cell for reproduction slows down and the cells stop reproducing as abundantly or in the same way as they did when we were younger. This preprogrammed change makes cells become abnormally shaped, which further changes the texture of the skin and prevents the cells from retaining water. This is why older skin tends to be drier than younger skin. This change in the skin's DNA and RNA seems to happen for a variety of reasons: it is genetically predetermined, a result of sun damage, and a result of an inflammatory response from free-radical damage built up in the skin cells over a period of time (Source: Annals of the New York Academy of Sciences, April 2001, pages 327–335).
You have probably connected the dots and noticed that many of these factors of aging are targeted by corresponding cosmetic ingredients that claim to counteract the effect of their naturally occurring depletion. Collagen, elastin, ceramide, hyaluronic acid, polysaccharide, DNA, RNA, and other skin components are popular additions to wrinkle creams. (DNA and RNA are the biggest jokes in this group of ingredients because not only don't you want to mess around with the cell's genetic coding, you can't. If you could, you would have the cure for cancer!)
Putting collagen and elastin in a skin-care product may sound convincing, but they can't bond to the collagen and elastin in your skin, although they can work as moisturizing ingredients. Ingredients like ceramides and hyaluronic acids do work to help support the intercellular structure of the skin, but there is no research demonstrating that they prevent its continuing depletion.
Good old glycerin is also abundant in the layers between the skin cells, and it's just as reliable in helping the skin to feel better, but the cosmetics industry doesn't talk much about glycerin because it is too commonplace to sound distinctive. Unfortunately, the cosmetics industry loves to use phrases such as "replaces what skin has lost" that lead you to believe these kinds of ingredients can affect skin structure in some permanent way. They can't. The point of all of this is that growing old cannot be reversed, much less with a skin-care routine or a handful of specific skin ingredients. What we can do is look for products that contain ingredients capable of helping skin to defend itself against environmental stress (with sunlight being the biggest culprit), reduce inflammation, encourage cell turnover to renew skin texture, and temporarily replenish what skin naturally loses as we grow older.
Source: Paula Begoun