What is aging skin?

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The appearance of aging skin consists of wrinkles, brown and red discoloration (photodamage), laxity and loss of muscle tone. Also associated with the appearance of the aging face is the lengthening of the upper lip, loss of volume in the mid-cheek, at the temple and in the chin, and a downturn of angle of the lips at the corner.

Are there different types of aging skin?

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There are two types of aging of the skin, “true” aging due to chronological age and “photo" aging, due to the toxic effects of cumulative sun exposure or other environmental toxins, such as smoking, pollution, and lack of circulating antioxidants (diet). The two types of aging manifest themselves in slightly different ways.

True aging results in a downward displacement of tissues due to the loss of skin resilience in counteracting the effects of gravity, resulting in sagging. There is also a loss of subcutaneous tissue (fat) in the central face resulting in a hollowed look. There are “lines of expression” or literal creases in the skin from the constant use of certain facial expressions such as laugh lines (crow’s feet, nasolabial folds), frown lines (lip creases and lines) and worry lines (forehead lines). If you had a couch in the same place on your rug for 20 years, you would not expect the carpet to spring back if you took the couch away. The same is true when you crease your face in a certain expression thousands of times over a lifetime- eventually the line just stays there.

Finally, the surface of the skin tends to have a “sallow" appearance- that is, dry, with a slight yellow tinge, which results from a slow down from the metabolic process yielding skin that does not renew frequently and looks "sluggish".

Photoaging, aging caused by ultraviolet light exposure, tends to act more on the surface of the skin. There are “sun freckles” (also known as “liver spots” although they have nothing to do with the liver) or irregular pigmentation and dilated blood vessels (often referred to as “broken” blood vessels) that lead to an overall uneven tone. Fine textural lines scattered over the surface are partly due to the loss of collagen’s integrity. Finally, there is laxity from the loss of elastic fibers. Excessive sun damage can yield pre-cancerous or cancerous growths (see section on skin cancer).

How can I treat aging skin?

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The treatment of aging changes of the face is diverse. Topical treatments consist of vitamin A derivatives, alpha hydroxy acids, vitamin C preparations, plant and botanical derivatives, antioxidants, growth factors and peptides. There are numerous types of chemical peels and microdermabrasions. Laser surgery and radiofrequency devices can be used to correct “sun freckles”, dilated blood vessels and wrinkles. BOTOX Cosmetic®, collagen, hyaluronic acid and fat injections can help with certain lines of expression and loss of facial fullness. New non-invasive tightening devices have come to the forefront to "replace" face-lifts. More major surgical procedures include laser resurfacing, face-lifts, brow lifts, and blepharoplasty (eyelid surgery). Topical treatments of aging •Vitamin A Derivatives (retinoids)- tretinoin (Retin-A, Renova),tazarotene (Tazorac,Avage), and adapalene (Differin) and various types of retinols. Of all the topical agents, the prescription retinoid creams have the most scientific evidence demonstrating they can reverse aging changes. Tretinoin has been shown to reduce fine lines, mottled hyperpigmentation (age and liver spots), and sun damage. The main problem with tretinoin and the other retinoids is that many people cannot tolerate the side effects of dryness and irritation that often accompany their use. There is sometimes a period of "retinization" that can last as long as two weeks that causes skin redness, peeling and discomfort. This is one of the reasons retinol creams have become popular - they are not as drying as Retin-A. Although the effects of retinol creams on human skin have been studied far less than that of the Rx retinoids, they hold great promise. A recent study shows that retinol does increase collagen in human skin. Vitamin A derivatives retinoids or retinols) are the cornerstone of any topical antiaging regimen, although people with rosacea and/or sensitive skin would be advised to avoid them as they tend to aggravate the condition by stimulating blood vessel growth. Reference the retinol products: Afirm, Dermal Repair • Alpha hydroxy and polyhydroxy acids (AHAs) – glycolic acid, lactic acid, gluconolactone In the early 1970’s the team of Van Scott and Yu discovered that alpha-hydroxy acids could dramatically improve severely dry skin. In the late 1980’s they formed a company called Neostrata, making them the first to develop and manufacture alpha-hydroxy acid “cosmeceutical” creams. The great thing about alpha and poly hydroxy acids is that they are inherently moisturizing. Since people with aging skin often have dry skin, it is an excellent choice. The alpha hydroxy acids (glycolic acid and lactic acid- derived from fruit acid and milk, respectively), confer a lot of benefits including smoother, softer skin, a pink “glow” and more even pigmentation. Their application results in an increase in collagen deposition, improved quality of elastic fibers and thickening of the epidermis (the layer of the skin that retains water and acts as a barrier to environmental insults). It is important to know what strength of free acid is present in the preparation one is using, because the higher the strength, the greater the benefits. Many creams that sport a high percentage on their label have been “neutralized’- that is, partially inactivated by a “base” to make the acid have less of a stinging feeling. This decreases the effective free acid percentage, and thus, their effectiveness at producing the desired results, although they are frequently more tolerable. The alpha hydroxy acid preparations are available as creams, lotions, gels, cleansers, and also as ingredients in chemical peels. Gluconolactones, or polyhydroxy acid products, appear to have most of the benefits of alpha hydroxy acids but are good for people with very sensitive skin. Furfuryladenine (Kinerase) Kinerase is a plant extract shown to delay the aging process in plants, fruitflies and human fibroblast cells (cells that make collagen). It may also act as a free radical scavenger, meaning that it has antioxidant properties and can protect cells from toxic insults. Its main advantage is that it is non-irritating. Many people cannot tolerate either the drying of the vitamin A derivatives or the stinging induced by the alpha hydroxy acids. For people with sensitive skin, Kinerase is a good choice. The jury, however, is still out regarding its effectiveness – no peer reviewed journal (articles accepted by an independent panel of experts in the subject chosen) has yet published a study. A preliminary study from the University of California Irvine has shown it to be effective in reducing fine wrinkles, coarse texture and blotchy pigment after 24 weeks of twice a day use. It represent a good choice for people with very sensitive skin and/or rosacea. Vitamin C Vitamin C is an antioxidant which sops up the toxic molecules that occur in skin cells when they are exposed to ultraviolet light. It has been shown to reduce skin damage from ultraviolet light in animals. It is very difficult to get a Vitamin C preparation adequately absorbed into the skin due to its low pH and other molecular factors and it is also unstable in solution, as the vitamin becomes easily inactivated when it is exposed to air or light. Different manufacturers of vitamin C products have made claims that their product has the special formula that makes it absorb into the skin and not lose potency. Although there is one published study showing that topical vitamin C reverses aging changes in humans, their is more evidence it will help to prevent (as opposed to reverse) aging changes, especially due to ultraviolet light induced damage . When Vitamin C “serum” first arrived on the scene, all my patients were clamoring for it, despite my warnings that no published data had emerged on its effectiveness and it was quite expensive. In the initial two years I dispensed it to hundreds of people, I was disappointed with the results. The fact that it was more expensive than most other antiaging preparations and didn’t seem as effective made it lose value in my eyes and I stopped carrying it in the office. I believe it could have a place as a preventative to sun damage in a way that is different from sunscreen, especially if they could figure out how to formulate it into a sunscreen. If you are determined to use a vitamin C product, I recommend the brand Skinceuticals, which is the original vitamin C formula developed by the dermatologist who did all the research on vitamin C’s effects as an antioxidant in skin (Dr. Sheldon Pinnell). These formulations appear at least to have shown a significant concentration of the product delivered to the skin. Beta-hydroxy acids Beta-hydroxy acid really is salicylic acid, an ages-old medicament used for various conditions which some contend isn’t really a “beta-hydroxy”, but it took on this popularized name after alpha-hydroxy acids came into vogue. Salicylic acid is used in many different types of medications and is related to aspirin (which is acetylsalicylic acid). It is used in antiaging products as a 1-2% concentration and can also smooth fine lines, improve surface texture and tone, in similar fashion to the alpha-hydroxy products. But salicylic acid also helps to clear pores, thus making it superior in this regard for the treatment of acne and coarse skin pores. Superficial peels with 20-30% beta-hydroxy (known as B-lift peels) can be effective if done repetitively to improve the surface of aged skin and fine lines, irregular pigment and even acne scars. (See more information below in the section on superficial chemical peels). Intermediate treatments of aging skin Chemical Peels Chemical peels involve the application of a liquid, gel or mask to the surface of the affected area (face, chest, neck, etc.) with the intention of lifting off some portion of the skin. The chemical is usually an acid that essentially “burns” the skin in a controlled fashion to a certain depth and then either stops or is neutralized. Afterwards, the layers of skin are sloughed off and new skin is formed. There are two important variables in chemical peeling- the strength or concentration of the solution and which chemical is chosen. • Superficial chemical peels Very superficial chemical peels are popular right now because there is little to no “down-time” which is why they are sometimes referred to as “lunchtime peels”. One can have these performed and go back to ones daily activities looking a little flushed: minimal peeling such as what you would get after a mild sunburn might ensue. These are done at regular intervals and are used to “jump-start” the effects of topical antiaging preparations. Very superficial chemical peels mainly remove the “dead” layer of skin (stratum corneum), but this appears to send a signal to the deeper layers of the skin to make new collagen. Very superficial chemical peels would include 20-30% salicylic acid (B-Lift peel), alpha hydroxy 20-30% glycolic acid peels (neutralized at the right time). Superficial chemical peels would include 15%-20 TCA (trichloroacetic acid) or the 11% TCA mask (Accupeel), and Jessner’s solution. These may include a few days of peeling and sloughing skin. Finally, similar effects and aftercare could be expected from light (very superficial) or medium (superficial) microdermabrasion. I find these a truly useful addition to the anitaging quest. Many of these peels can be done for a limited expense, very low risk of an adverse reaction and no time away from the activities of daily life! However the effects are gradual and modest, requiring multiple treatments and the ongoing use of antiaging topical medications and frequent maintenance. Another advantage of the very superficial peels is that they can be used safely on people with darker skin tones, whereas higher strength peels can cause hyperpigmentation (excess pigment) in the healing stages. My current personal favorite is the B-Lift peel- it is simple, inexpensive and I’ve never seen any major problems with it. It needs to be done at least a few times to have any lasting effect. Medium depth chemical peels Medium depth chemical peels are best when the aging is moderate to severe and one wants to have one treatment and not many. There is usually significant sloughing of the top layer of skin for about a week to 10 days that is unsightly enough that you wouldn’t want to go out in public. However, the effect of this one peel is much more dramatic than with one light peel . The risks are also proportionately greater and include possible hyper- or hypo-pigmentation (skin which is too dark or too light) , prolonged erythema (redness) and even scarring . The main chemicals are 35% TCA, 50-70% glycolic acid, 16% TCA mask (Accupeel) or combination peels (Jessner’s solution plus TCA, carbon dioxide and TCA, etc.). Although there are some practitioners who are really skilled with these peels, lasers have supplanted much of the use of these peels because of the ability to more precisely gauge the depth of the wounding (see below in laser section). However, practitioners of the new TCA mask claim it makes up for some of the unpredictability of other types of peels and peels are usually less expensive than laser resurfacing. • Deep chemical peels: A deep chemical peel is a phenol peel or a 50% TCA peel . These peels are appropriate for only the most severe photodamage. Phenol peels need to be performed with cardiac monitors (if done on more than just a small area of the face) because the absorption of the chemical can cause heart rhythm abnormalities. Although there may be some evidence that this might get superior results when compared with carbon dioxide laser resurfacing, it has become a dying art with the advent of lasers. Often, people get a kind of “porcelain” white appearance after this, so it should not be performed on dark-toned skin. • Microdermabrasion This is a machine that looks like a small vacuum cleaner that has a hand piece on it with suction which is put against the face or affected area. The suction then lifts up the skin and bombards it with tiny aluminum oxide crystals that lightly abrade the surface in a very uniform way. The depth of penetration can be increased by changing the pressure in the machine or the number of times the skin is passed over. Thus, one can get a deep abrasion, similar to a dermabrasion if used this way, with similar profound changes in the skin. Most practitioners however, utilize nurses or aestheticians to provide more superficial treatments weekly or biweekly for 4-10 sessions to get the desired results. The aftercare is usually a bland moisturizer and one typically has a slightly sunburned appearance with mild peeling for a few days. Many experienced and trusted dermatologists are enthusiastic about this device’s capabilities, although little has been published in the medical literature. These appear to offer similar results to a series of superficial chemical peels, possibly at a slightly higher cost depending on where you live. It is better if you get your treatments in a reputable dermatologist’s office, rather than at a salon. Even though it may be an aesthetician performing the treatment in both places, the dermatologist took the time to train the aesthetician and oversee her work, as well as continuing to update her information about how to perform better treatments and get better results. In salons the training is performed by the company manufacturing the equipment, and the knowledge base is rarely extended. Botox. Originally used and approved by the FDA for blepharospasm and strabismus (abnormalities in eye muscles), injectable botulinum toxin was “discovered” by Dr. Jean Carruthers, a Canadian ophthalmologist who noticed it was improving the wrinkles around the eyes in her patients. She and her husband Alastair, a dermatologist, went on to explore its uses and the Botox phenomenon of was born. It is the number one cosmetic treatment worldwide. The main uses for Botox cosmetic are for the frown lines between the brow, on the forehead and the wrinkles around the eyes. Botox is made up of botulinum toxin, one of the most potent poisons known to mankind. Its principal action is to paralyze muscle. When used in small dilutions in a controlled fashion by a skilled physician with extensive knowledge of the anatomy of the face, it has a surprisingly good safety record. Many of the larger wrinkles on the face are really “lines of expression”. This means that they are creases formed by the repetitive movement of characteristic facial expressions. When a person frowns a certain way and after many years and many frowns the skin forms a crease where it was repeatedly bent as a result of the muscular action. The amazing thing about botox is that when you relax the muscles involved, you can actually make the crease go partially or completely away. The main side effect of Botox is too much muscle relaxation in muscles that were not targeted, leading to eyelid or brow drooping. This is caused by an injection that is too close to the muscle that lifts up the eyelid or the solution diffuses to that area, hence paralyzing its function. Occasionally people get headaches (although ironically using Botox has become a new and very effective treatment for headaches ). Some people don’t like the fact that they can’t frown as it limits their facial expressivity. However, with skilled injections, facial expressivity is maintained. Botox is also being used for hyperhidrosis (it has recently been approved for this use by the FDA), a condition of excess sweating of the hands, axillae (underarms) or feet. The main limiting feature of Botox is that its effects are temporary. While this may be a good thing if you have a side effect, it becomes quite an expense to have to get it repeated every 3-4 months, at somewhere in the range of $3-800 per treatment. Some people have found that after repeated injections they don't make the involuntary expressions leading to the crease, resulting in a kind of "biofeedback" on the muscles so that Botox is not needed as frequently to maintain the effect. Injectable Fillers: Collagen (Zyderm, Zyplast) and Hyaluronic Acid (Restylane Fine Lines, Restylane, Perlane, Hyalaform, Hyalaform Plus) Injectable fillers are materials made from collagen or hyaluronic acid that are injected into wrinkles to erase them. It is a very effective treatment and also affords instant gratification, in that the results are immediate. Like botox, the effects are temporary because eventually the body metabolizes and reabsorbs the material. Collagen and Hyalaform injections need to be repeated every 3-6 months for maintenance and it appears that Restylane lasts more like 6-9 months, depending on the area. The advent of Restylane has caused a lot of excitement in the aesthetic arena. It has considerably more volume replacement properties than other fillers, allowing skilled practitioners to be able to artistically sculpt the face. One of the most common areas it is used is the nasolabial folds and in the wrinkles around the mouth. The biggest problem with collagen is that it causes allergic reactions in a small percentage of people. It is very important to undergo collagen skin testing twice. The first test area is observed for an entire month, because the allergy can be delayed for some time. Then a second test is performed because there is a small fraction of people who become allergic to it upon re-exposure. These two tests screen out more than 99% of people who would be allergic. Another concern with collagen that surfaced around the same time as the breast implant scare was whether or not it could cause collagen vascular diseases (arthritis and/or autoimmune types of diseases). Although this has never been born out in any medical studies, it still is recommended to avoid collagen injections if there is a personal history of lupus, rheumatoid arthritis or scleroderma. However, many thousands of people have had these injections for over 20 years and collagen has an excellent safety record. This is one of my favorite procedures to perform. It is artistic and people are always shocked and delighted when they look in the mirror for the first time immediately after the procedure. In the last few years a number of competitors to collagen have surfaced . There is Dermolagen, a product that is derived from human cadavers that have been tissue banked. This is ideal for the collagen allergic patient, as there are rarely if ever allergic reactions to this substance. One has to be concerned also with potential infectious agents, although the materials are subjected to the highest possible scrutiny as well as sanitizing procedures and are approved by the tissue banking authority. Some have complained that this material is more painful on injection than collagen and requires nerve blocks (anesthetic blocks like the dentist gives you). There is also Autologen or Isolagen, procedures which yield collagen grown from a small piece of skin taken from the same person for whom it will be used (left over from another surgical procedure or a small amount removed from behind the ear). Although in theory this sounds ideal since it overcomes the problems of allergic responses and infectious agents, it appears to be difficult to produce enough material in a cost-effective manner and appears to require multiple treatment sessions. This may change, however, as technology improves. Injectable fat has many advocates. This is a procedure where a person’s fat is “harvested” (removed) from one area (typically the thighs or buttocks) by liposuction and re-injected into facial creases . This technique overcomes the problem of allergy and also addresses the impermanence issue. It appears that after multiple treatment sessions the fat settles in and “takes” and it is possible to get perhaps a 30% permanent correction . Surgical approaches to aging The surgical approaches to aging include laser resurfacing, face-lifting (rhytidectomy), brow-lifting, eyelid surgery (blepharoplasty) and liposuction of the face. When the skin is severely damaged, superficial and moderate measures may not be enough to really reverse the damage and significantly alter the appearance. This is true when the surface wrinkles and textural and color mottling are severe and/or the gravitational forces have overwhelmed the body’s defenses. The jaw sags, the mid-face sags, the upper lip lengthens and the eyelids droop. Although superficial peels and antiaging topical therapy may afford some improvement, a more aggressive approach is often needed. • Laser Resurfacing In the mid-1990’s a revolution took place in aesthetic surgery with the advent of the high-intensity pulsed carbon dioxide laser . These machines were capable of delivering a predictable depth of penetration into the skin, so that one could almost “sculpt” away wrinkles and scars. In addition, studies showed that there was “collagen shrinkage”, which meant that for the first time one might be able to actually tighten the face, or reverse some of the sagging which heretofore had only been able to be accomplished via face-lifts. After a period of time it became apparent that this procedure had considerable risks as well. Many of the risks were actually quite similar to medium and deep chemical peels and could be predicted by the depth of the tissue wounding. These include prolonged redness, often lasting up to 6 months after the procedure , hyperpigmentation (blotchy dark discoloration) which also resolved with treatment and time, and most disconcerting, a white appearance that occurs many months after the procedure and appears to be irreversible in a small percentage of those treated . The introduction of the erbium YAG laser was heralded as the end of the complications of laser resurfacing . This laser is more purely “ablative” meaning that it vaporizes the tissue but doesn’t heat it. Many researchers had related the long course of redness and other complications to the “zone of thermal necrosis”, that is, a depth of heating that didn’t occur with the erbium laser. Also, it appeared to be safer on darker skin types as well as requiring less anesthesia. More recently, however, it has been discovered that there is a price to pay for less risk and that appears to be decreased effectiveness. Although the erbium procedures appear to be faster and easier to recover from, they don’t provide the tissue tightening one can get with the carbon dioxide lasers, thus are more useful for those with mild to moderate aging changes. New “hybrid” models of laser resurfacing have sprung up to address these issues. These are “combined” erbium and carbon dioxide lasers and appear to have some of the advantages of both, while having less of the disadvantages of either . The carbon dioxide, erbium and hybrid lasers are in widespread use today. When they are used for the appropriate reasons and their limitations are recognized, the person undergoing the procedure understands the risks fully and postoperative care is maximized , these are excellent treatments for moderate to severe aging of the face. • Other laser procedures The newest laser procedures involve trying to rejuvenate the skin without actually removing or burning the top layer, sometimes called subsurface or noninvasive resurfacing. One procedure involves another wavelength of YAG laser at 1320 NM (Cool Touch) which heats up the upper layer of skin causing a remodeling process. The other employs an intense pulsed light source (Photoderm, Multilight or Vasculight) to focus heat on dilated blood vessels in the upper layer of skin and achieve the same remodeling and production of new skin . Both of these procedures require multiple treatments but one can return to one’s activities immediately and they have very low risk. The procedure utilizing an intense pulsed light source is called photorejuvenation. Photorejuvenation procedure works especially well on sun damaged skin with many dilated blood vessels and sun freckles. This is a relatively new procedure and I have been extremely pleased with the results in my patients thus far. • Other surgical procedures When the lower eyelids are puffy, the upper eyelids droop significantly and the skin of the face is very loose, traditional surgery is probably necessary to correct the problem. Procedures such as eyelid surgery (blepharoplasty) and face-lift surgery (rhytidectomy) are time-honored methods of correcting these problems. The long history of these procedures has allowed plastic surgeons and ophthalmologists to perfect the procedures and make their complications less common.

Is aging skin curable?

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Why treat aging?

Seeking out the best appearance one may attain is common to the treatment of many skin diseases including such “medical” diseases as acne and psoriasis, where it is well-documented that treatment improves ones self-esteem and quality of life. We all strive to stave off the loss of our physical and mental abilities as we age, as well.

There are some within the field of dermatology who criticize the new interest in the treatment of aging as an exercise in greed and an escape from the rigors of scientific inquiry. These same people claim that due to the constraints of managed care, dermatologists are mainly looking to improve their bottom line and are therefore preoccupied with cosmetic procedures. This is far too simplistic. For one thing, the science of the senescence of cells and tissues is no less challenging than any other biological mechanism. For another, real people benefit in real ways.

Humankind will always struggle against their limitations, the principal one being their finite time on earth. Struggling against the progressive loss of youthful appearance seems natural as long as it is put into perspective and does not become the focus of one’s life. Perhaps through future research we can understand the biology of aging enough to move on to a new phase in medicine, one that some call the paradigm for medical science in the 21st century, when we focus more on wellness and prevention than on eradication of disease and abnormal physiology.

What does aging skin look like?

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A few examples of sun damaged skin vs non-sundamaged skin are the arms and the chin areaa. If you look at the inside surface of your upper arm you will see a lighter toned skin where the “sun has rarely shone”. Compare this to the outside of the arm, and you can see the “staining” effect of the sun on the skin. Similarly, you can see these effects on your neck if you look in a mirror. Given enough sun exposure to the surrounding areas, there will be a subtle and even “v” outlined below your chin, where the skin has been shielded from the sun by your chin. The mottled pigmentation of the sides of the neck is missing here because of your chin “sunbrella”.

See the section above "What are the different types?" for further examples.

How can I find out more?

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Where did this information come from?

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