What’s In It?
a look at current skin care ingredients

“To improve the patient’s complexion, the skin was cleansed and then the alpha hydroxy acid solution was applied to the client’s face.”

Although this sounds like almost any current spa treatment, the example dates back to the time of the ancient Egyptians. New ingredients are being discovered all the time-ingredients that tout anti-aging benefits for all who use them. To the skin care professional, keeping up with what to use and when to use is a daunting task, but can be managed with some specific information. First and foremost, before you dispense XYZ cream for use on your client, you need to ask “What’s in it?”

In this article, we will evaluate many of the current and new skin care ingredients that are included in many formulations and cover pros and cons.

Crash course on skin anatomy-

Prior to a review on skin care ingredients, it is important to review the skin anatomy and the changes that occur over time.

Our skin has two basic layers: the epidermis and the dermis. The epidermis is the outermost layer of our skin and consists of five different layers. The dermis is the supporting layer of skin which actually contains the collage fibers. Pigment cells or melenocytes sit directly in between these two layers of skin. The collagen fibers are what provide the skin with its intrinsic support. Collagen support acts very similarly to the metal “rebar” rods that are laid down in concrete to support buildings and bridges. In the aging process, if one avoids the sun, the epidermis begins to thin. As a result, the collagen, in the dermis, begins to break down and fine wrinkles may begin to form in the skin.

Ultraviolet radiation from the sun causes the epidermis to thicken in a manner similar to yard work causing callousness to develop on the hands. The epidermis thickens to protect the skin from harmful radiation.

In the dermis, we see an accelerated breakdown of collagen resulting in further wrinkle formation. As a result of sun exposure, the pigment cells begin to cluster, possibly resulting in brown spots. The following ingredients have been demonstrated to reverse many of these changes and in some cases slow down the aging process.

Hydroxy Acids

These are fruity acids and can be divided into four different groups: alpha hydroxy acids (AHA), beta hydroxy acids (BHA), combination hydroxy acids (CHA) and poly-hydroxy acids (PHA).

Alpha hydroxy acids: These ingredients have been very popular in skin care treatments and there are three subcategories: the monocarboxylic acids (lactic and mandelic), dicarboxylic acids (malic and tartaric) and cryboxylic acids (citric acid).

The alpha hydroxy acids penetrate through the epidermis and cause a thinning of the dermis by disrupting the bonds between some of the outer layers of the epidermis, resulting in a fairly rapid thinning of the epidermis. Because the alpha hydroxy acids also penetrate down to the dermis, there is commonly some stinging associated with the application of the products. They are ordinarily used as peeling agents.

For AHA products used by trained estheticians, the Cosmetic Ingredient Review Panel concluded the formulations of glycolic acid and lactic acid at concentrations of 30 percent or less and a pH of 3.0 or greater (intended for only “brief” use at one time followed by thorough rinsing and daily use of sun protection) are safe. It is very important that glycolic peels be neutralized; otherwise, they may result in a chemical burn.

Alpha hydroxy acids that are in un-buffered formulations (as opposed to buffered solutions) tend to have a greater effect on the skin. One of the significant benefits of alpha hydroxy acids is that they do not increase the blood vessels in the skin like some other agents. Therefore, they do not result in redness of the face.

Lactic acid in a concentration of 12 percent has been shown to increase skin moisturization, especially of the lower legs and arms, which can result in smoother feeling skin.

Beta hydroxy acids: The only member of the group is salicylic acid, which is unique among the hydroxy acids because it can enter the sebaceous units, and will result in exfoliation in oily areas of the face. This particular quality becomes very important for acne patients and therefore these acids are commonly found in acne preparations.

It also acts to exfoliate the skin layer by layer as opposed to the alpha hydroxy acids, which tend to separate the epidermis in a deeper layer. Salicylic acid can be used as a peeling agent in 10 percent to 50 percent solutions. In contrast to glycolic acids, salicylic acid is a self-neutralizing peel that ends with the formation of white crystals on the skin. The crystals can easily be washed off with water.

Because the effects of salicylic acid do not extend down into the dermis, it is usually more comfortable and is ideal for acne patients, those with sensitive skin, or patients with rosacea.

Combination hydroxy acids: Many formulations now contain both alpha hydroxy acids and beta hydroxy acids to try to obtain the benefits of both of these different groups. Unfortunately, the AHAs and BHAs are most effective at different pH levels, so most products will be either AHA or BHA dominant depending upon the pH of the solution.

Poly-hydroxy acids: Because the alpha hydroxy acids penetrate quickly down to the dermis and cause stinging and burning, many cosmetic companies are trying PHAs. This larger molecule does not penetrate through the epidermis as quickly and rarely will penetrate down to the dermis. Therefore, it is much gentler on the skin and will tend to decrease customer complaints of stinging, burning, and itching. The downside: because it does not penetrate down to the dermis, one should not expect an improvement in wrinkles.

Vitamins

These are ingredients that are commonly found in skin care formulations. Many of the vitamins found in over-the-counter preparations, due to the metabolism of the skin, can be converted to active ingredients, which are often found in prescription medications.

Vitamin A: Vitamin A or retinol is a potent antioxidant which can be converted in the skin to retinoic acid or tretinoin, a “prescription” item. Unfortunately, only small amounts of the retinol are converted by the skin, thus accounting for the increased efficacy seen with prescription preparations containing tretinoin. When used topically, vitamin A is known to act as a humectant: it attracts water from the dermis as well as the epidermis. This aids in hydration of the skin. It also increases blood flow to the skin resulting in a reddish complexion and is not generally recommended for patients with rosacea. Retinal palmate is commonly used in moisturizers to prevent the oxidation of other lipids in the formulation.

Vitamin C: This vitamin, another powerful antioxidant, is extremely important to the proper functioning of the skin. The active form of vitamin C is called L-ascorbic acid. Body sources of vitamin C supply only 1500mgs, and vitamin C depletion occurs rapidly upon exposure to the sunlight, so consumption of fruits and vegetables is necessary to maintain a constant body supply. This is a much more consistent method than the use of topical vitamin C preparations. Some animal studies have shown enhanced vitamin C levels following topical application of 10 percent L-ascorbic acid solutions. However, these have not been confirmed in humans.

Vitamin E: This is a broad group of agents including tocopherols and tocotrienols. The only active forms are the alpha and gamma tocopherols. The alpha is a much more active agent than the gamma tocopherols. It is a well known antioxidant and appears to improve moisturization, softness and smoothness of the skin. The alpha tocopherols are also used as a preservative formulation to help prevent the spoiling of fats.

Panthanol: This is converted to pantothenic acid, also known as vitamin B5 in the skin. It is widely used as a skin and hair conditioning agent in moisturizers, shampoos, and hair sprays for its function as a humectant holder and its ability to attract water to the skin.

Niacinamide: This form of niacin is found throughout the body including the skin. It appears to have both anti-acne and anti-aging properties.

Kinerase (N6 Furfuryladeninei): This agent, originally derived from plants, functions differently from those previously named. Rather than being a “de-wrinkler” of the skin, it actually slows down the aging process. Since Kinerase decreases skin redness, it is an excellent treatment for rosacea, poikiloderma and any ruddy looking skin. Patients with dry skin, or sensitivity/intolerance to Retin-A, may find kinerase a welcome treatment. It is less effective on thick, oily skin.

Hydroquinone: Pigmentation problems may result from an uneven distribution of melanin over the skin surface. Hydroquinone is a powerful tyrosinase inhibitor and pigment-lightening agent. The FDA has approved a maximum 2 percent concentration in a cosmetic formulation for use without a prescription. Concentrations of 2 percent hydroquinone blended into an AHA vehicle provide excellent results in conjunction with the daily use of sunscreen.

Kojic acid: This is used widely in Japan as a lightening agent and is a tyrosinase inhibitor. When used with sunscreen preparations, kojic acid can inhibit UV-caused redness and can accelerate wound healing. This is also highly recommended as an ingredient for skin bleaching.

Epidermal growth factor (EGF): A protein derived from fermented yeast, it is used to address skin problems from acne to aging. EGF stimulates new skin cells to generate rapidly, helping the skin to heal itself; thus reducing stress on the skin associated with intrinsic and extrinsic aging.

Spin traps: This new kind of protection is called phenylbutyl nitrone (PBN). Spin trap molecules found in minerals and proteins stop unstable free-radical electrons. Research show spin trap molecules preserve radicals for use in the body’s production of antioxidant glutathione and superoxide dismutase. Scientists have proven nitrone spin traps to be highly effective in reversing signs of aging in the skin. These powerful molecules offer us control over the way we age.

With the multitude of ingredients available, it is important for patients to work with a well-trained esthetician and physician to help them accomplish their goals.

Dr. Brian P. Maloney
Facial Plastic Surgeon
Atlanta, GA