Aging is an inevitable process that occurs in every cell in every organ in every living thing. Our skin also participates in this process. Recently more focus has been given to methods of aging prevention. Many of these involve procedures that are performed in the doctor’s office, but there are also ways to prevent aging that you can do at home. In the future we will see more products directed to at home users, including peels, topicals and even at home laser systems.
The causes of aging can be divided into two main categories: intrinsic and extrinsic. Intrinsic factors of aging include your genetic predisposition, skin color, skin type (oily or dry) and even skin thickness. These are primarily predetermined and are difficult to alter. You can predict how much you will be affected by these intrinsic causes by examining your parents and grandparents aging process. Clinically, intrinsic aged skin is pale with fine wrinkling. Extrinsic causes of aging include ultraviolet radiation (sun exposure, tanning), smoking, diet, and even climate factors. The extrinsic causes can be altered by our behavior, and are an excellent place to start on an anti-aging regimen. Most data predict that 80% of our aging is due to extrinsic factors. Excessive sun exposure causes skin to be pigmented and coarse with leathery type wrinkling. Gravity and hormonal changes also play an important role. Women tend to age differently than men due to hormonal effects on sebaceous (sweat) glands. Our better understanding of aging skin has led to more sophisticated products to combat this. The days of using a thick moisturizer with no added ingredients are essentially over. The process of deciding what products to use can be daunting. This chapter will educate you on the types of products available, when and for what purposes they should be used.
An at home anti-aging regimen should always start with topical therapies. Most of these need to be used on a consistent basis for results and many have strong scientific data showing they can improve aging skin. Topical creams, potions, serums, or lotions, with added ingredients are termed ‘cosmeceuticals’.
Cosmeceuticals are not medications and are not regulated by the food and drug administration (FDA). They are not marketed to cure any condition, even aging. Furthermore, they are not required to prove their benefit, but only their safety to the regulating committees. It is more useful to the consumer to understand the classification of products than to attempt to analyze each individual one.
There are several groups of cosmeceuticals on the market. We will cover the main categories, including anti-oxidants, hydroxyacids, other vitamins, peptides, bioengineered products, and retinoids. There is some overlap in these categories, for example, some peptides function as anti-oxidants and vice-versa. I cannot emphasize enough the importance of sun protection, not only for skin cancer prevention, but also for prevention of aging. Ultraviolet radiation causes direct damage to DNA and well as the production of free radicals which also lead to cell damage. For those who have Vitamin D concerns, speak to your physician about vitamin D supplements. There is some evidence that as we age, there is no amount of sunlight exposure that can give us the Vitamin D production that we need.
Anti-oxidants are a very popular cosmeceutical on the market today. Most people have heard of anti-oxidants, as we often take them as vitamin supplements. These same types of vitamins are available in topical formulations as well as the oral tablets. Why put them on topically when you can take them orally? The skin has a transport system the takes molecules from the blood stream and into the skin. This transport system can only carry so much of one particular vitamin before it becomes overloaded. In order to put an excess amount of vitamin into the skin, in many cases, it must bypass the internal transport system and be placed directly onto the skin. The skin is a tight protective sheath with the purpose of guarding our inside from the outside world. That being said, not all topical are able to penetrate thru the tight pores of the skin. Many molecules, such as collagen and other growth factors, are too large to actually penetrate deep into the skin. Scientists have become more adept over the years in designing smaller versions of large molecules, and even carriers which will bring large molecules into the skin from a topical formulation. All of these new topical technologies are being introduced into the market every day.
Anti-oxidants are plentiful in our world and we are even able to synthesize them ourselves in some cases. They can be found in citrus fruits and in leafy vegetables. They are used by our skin to neutralize free radicals. Free radicals are unstable and lead to collagen breakdown and cell damage, including cell death. Free radicals are produced every day by our cells, even without any extrinsic stressors such as UV radiation. Lucky for us our bodies have anti-oxidants which counteract most of the free radicals. When our anti-oxidants get overwhelmed, we end up with cell damage. Taking an oral anti-oxidant can help resupply our system with anti-oxidants. Applying directly to the site being treated, such as the skin, brings the vitamin directly to its needed location.
Anti-oxidants used in anti-aging include: Vitamin C, Vitamin, E, co-enzyme Q10, alpha-lipoic acid, coffee berry, Ferulic acid and idebenone.
Some of these topical anti-oxidants also offer protection from damaging sun exposure. I have my patients use their anti-oxidant under their sunscreen to provide an additional layer of protection, especially when living in or visiting a sunny climate like Miami. There are millions of anti-oxidant products on the market, and choosing the right one for you will depend on several factors. Many people choose their topical based on texture. Serum formulations of any cosmeceutical are generally the lightest, and creams are often the heaviest. Some of the anti-oxidants are highly unstable when exposed to light and oxygen, and hence, must be packaged in a dark container with a small opening at the top.
Hydroxyacids are used in topical anti-aging regimens as well as at home and in office peels. They come in several varieties including: Alpha, Beta, and poly hydroxyacids. Alpha hydroxyacids (AHAs) include glycolic acid, lactic acid, and citric acid. These acids are great at exfoliating and come in a variety of strengths. Glycolic acid is the most common AHA used in anti-aging regimens. It has been shown to increase cell turnover and help with collagen production. It can be irritating to sensitive skin and may not be a good choice for those patients with rosacea or red skin. Gluconolactone or polylactic acid, second and third generation AHAs, are a more tolerable choice for those who become excessively dry from glycolic formulations.
The most popular beta hydroxyacid (BHA) is salicylic acid. Though used in some anti-aging products, salicylic acid has found its best use in acne prone patients. Salicylic acid is also used in peels and is a good choice for dark skin patients. It is similar to AHAs in its ability to exfoliate the top layer of skin preventing clogging of pores and subsequent larger acne lesions.
Retinoids are among the most studied of all the anti-aging ingredients. Retinoids as a category originate from vitamin A. The active ingredient is retinoic acid. Several of the prescription forms of retinoids have retinoic acid as their main ingredient. The over the counter cosmeceutical ingredient is retinol. Retinol gets converted in the skin to retinoic acid. The strengths of retinol to retinoic acid are thus different and generally speaking, a .1% retinol product is proportional to a .01% retinoic acid product. Other precursor molecules to retinoic acid are also available in cosmeceutical preparations including retinyl palmitate, retinyl proprionate, retinyl acetate, and retinaldehyde. Retinoids are able to increase cell turnover, stimulate collagen production, reduce abnormal pigmentation, and inhibit the breakdown of collagen. Retinoids are also used in oral form to prevent skin cancer formation. Initial use of any retinoid may cause peeling, dryness or even irritation. This does not mean that you cannot use a retinoid. Start with a pea size application at night and slowly increase the frequency and quantity of applications as tolerated. Retinoids are a favorite anti-aging ingredient among dermatologists, including myself. Their multiple actions and extensive scientific data support their use for anti-aging.
Peptides are strings of amino acids forming short chains of proteins. Products containing peptides can be found in many anti-aging regimens that range from inexpensive to very costly. Peptide products include the tripeptide-copper complex glycyl-histidyl-lysine-Cu (GHK-Cu), acetyl hexapeptide-3 (AH3 or Argireline), and the palmitoyl pentapeptide palmitoyl-lysine-threonine-threonine-lysine-serine (pal-KTTKS). Initially studied as an agent in wound healing, GHK-Cu has been proven to increase collagen and glycosaminoglycans (important building blocks of skin), including hyaluronic acids, both in vitro and in vivo. Copper peptides have also shown and been advertised to increase elastin synthesis, promote removal of damaged skin, improve skin tone, decrease wrinkles, and to have anti-inflammatory and anti-oxidant effects.
AH3 has been added to topical products for its advertised ability to reduce the appearance and depth of fine lines and wrinkles on the face and neck, improve skin texture and tone, and increase hydration. This peptide reportedly relaxes facial muscles through inhibitory signals making its action similar to that of botulinum toxin. However, there is no clinical data to show that it works like botulinum toxin in a clinical setting.
Pentapeptide pal-KTTKS is a bioengineered material intended to improve facial wrinkles. In a double-blind, randomized, placebo controlled study, 93 Caucasian women applied pal-KTTKS to one side of their face and a placebo moisturizer to the other side. After 12 weeks of treatment, objective and subjective measures showed a significant improvement in facial rhytids on the pal-KTTKS treated side versus the control side. Though its exact mechanism of action is unclear, pal-KTTKS has shown to increase collagen type I and IV. The same peptide is used by several companies in different concentrations in various topical products.
Another group of bioengineered molecules include the growth factors. Already a part of natural wound healing, growth factors are an important part of the wound healing process. Many studies have shown the ability of growth factors to restore tissue integrity of aging skin by thickening the epidermis, decreasing rhytids, and increasing collagen growth. So why don’t we use growth factors in every product? The problem with growth factors is there size. They are large proteins composed of hundreds of amino acids. (By contrast, the peptide products contain around 5 amino acids.) The size of these growth factors alone is a limiting factor to penetration, even without discussing stability or vehicle preparations. Large concentrations of these agents need to be included into the creams in order to allow for penetration. This however, can make these topicals very expensive to produce. Transforming Growth Factor-b1 (TGF-b1), present in many tissues, is an example of a growth factor used both in wound healing and in topical formulations for both intrinsically and extrinsically aged skin. This growth factor is involved in wound healing and helps in collagen production. TGF-b is a large protein, so penetration into the skin is one downfall to this therapy. However, in a human study comparing 2 differently formulated topical creams containing TGF-b1 (CRS and TNS) to each other and to a topical Vitamin C cream alone in the treatment of facial rhytids, the two creams with growth factors had superior results as compared to the Vitamin C cream. Both growth factor containing creams were well-tolerated and showed statistically significant improvement in rhytids after 3 months of treatment. Another human study of TNS (Nouricel-MD, a product containing various growth hormones) by Fitzpatrick showed improvement of skin texture and wrinkles with histological confirmation of increased collagen synthesis and thickening of the epidermis. Growth factor creams can be some of the most expensive on the market due to the cost of production and the need for high concentrations to achieve effective penetration through skin.
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