Skin Science


What is skin aging?

     Research has shown that there are two main causes of skin aging. The first cause of aging is the inevitable natural aging process itself, which is inherited and a direct result of our genetic make-up. This type of aging is called intrinsic aging or chronological aging. Over time, physiological factors cause the skin to produce fine wrinkles, become thin and transparent, and loose its elasticity (its ability to stretch and maintain its shape). Both a loss of fat under the skin and gravity pulling the skin down causes the skin to sag. Genes control when these symptoms will appear. Aging skin may become apparent as early as one’s 20s or as late as one’s 40s.

     The second cause of skin aging is due to extrinsic factors or external environmental factors, many of which are preventable. These factors include, but are not limited to, ultraviolet light exposure and cigarette smoking. Skin experts refer to damage caused by the sun’s ultraviolet rays as “photoaging.” Photoaging is responsible for the majority of premature sun damage to the skin, and has been shown to accelerate the intrinsic aging process. Just a few minutes of sun exposure each day over the course of many years, can cause significant cutaneous damage. The sun’s ultraviolet rays may cause the development of pigmentation (freckling and age spots), fine blood vessels, a leathery and rough appearance to the skin, wrinkling, warty like growths called actinic keratosis, and even skin cancer.

What is an anti-aging/wrinkle cream?

     Moisturizers specifically designed to address the signs of aging are classified as anti-aging products. Simply stated, anti-aging products ARE moisturizers that CLAIM to improve skin tone, texture, and radiance, while reducing wrinkling.

     Manufacturers have added active ingredients to moisturizers with the intent of improving the signs of aging; however, there is little evidence that these active ingredients are the direct cause of any improvement in fine lines and wrinkles. As moisturizers, anti-wrinkle creams increase hydration of the skin temporarily reducing the appearance of fine lines and wrinkles!

     Unlike prescription creams, over-the-counter (OTC) anti-aging creams are not subject to review by the Food and Drug Administration (FDA). Prescription creams are classified as drugs, which requires the manufacturer to prove both the safety and efficacy of the product. Anti-aging creams (OTC) are classified as cosmetics and, therefore, manufacturers do not need to prove the product’s efficacy to back up claims. Anti-aging products contain a very low concentration of active ingredients and, as cosmetics, are not regulated by the FDA.

What are the most common anti-aging ingredients added to moisturizers?

  • Alpha Hydroxy Acids,

     Alpha hydroxy acids (AHAs) are a group of naturally occurring acids commonly found in certain foods. Because of their abundance in many fruits, alpha hydroxy acids are commonly referred to as fruit acids (citrus acid from citrus fruit, malic acid from apples, tartaric acid from grapes.) Ironically, the two most common alpha hydroxy acids are not found in fruit (glycolic acid from sugar cane juice and lactic acid found predominantly in sour milk.)

     Alpha hydroxy acids have been used successfully to treat extremely dry and flaky skin and have been shown to temporarily improve the appearance of photo-aged skin. Many studies have proven AHA’s moisturizing ability (to increase the water content of skin) and have concluded that AHAs enhance the shedding of the most superficial dead skin cells, leaving the skin looking more uniform and feeling smoother and more supple. Some studies claim that AHAs improve the protein structure of the skin that makes up the skin’s strength, but the evidence to support these claims is lacking.

     Clinical studies have also shown that the most beneficial effects of AHAs occur at concentrations and at a pH unavailable in over-the-counter (OTC) products. Although OTC moisturizers containing AHAs may be adequate moisturizers, and may temporarily reduce the appearance of fine wrinkles and skin dryness, skin-rejuvenating claims are unproven.

     When applied to the skin, skin care products containing AHAs may cause irritation and burning. This may depend on the concentration and pH level of the product; unfortunately, this information is not always available on the product label. It is recommended to use products that identify the concentration of active ingredients. Despite their popularity, and their effectiveness as moisturizers, the exact mechanism of action of alpha hydroxy acids remain unknown. Studies show that AHAs may increase sensitivity to UV radiation. Sunscreen application is advised when using these products.

  • Retinoids

     Vitamin A and its derivatives (retinoids) are possibly the most prevalent anti-aging ingredients on the market today. These derivatives include vitamin alcohol (retinol), vitamin A esters (retinyl palmitate, retinyl acetate), and vitamin A aldehyde (retinal). Retinoic acid (tretinoin), an FDA approved retinoid, is the gold standard for photo rejuvenation and skin repair. Retinoic acid is only available by prescription and is NOT found in OTC skin products. The weaker derivatives of retinoic acid are commonly found in over the counter skin care products. Evidence of the efficacy of these weaker retinoids is much less robust, but is probably higher than most other “anti-wrinkle” ingredients. The majority of studies evaluating the benefits of these OTC retinoids are poorly designed, and the effectiveness of these preparations by most skin experts is regarded as marginal at best. Vitamin A derivatives must be avoided during pregnancy as they may increase the risk of birth defects.

  • Antioxidants

     Many age-defying skin care products on the market contain “antioxidants.” These products claim to diminish the signs of aging.

     What are antioxidants?  All living things utilize oxygen to harvest the energy our cells need for survival. Oxygen controls the chemical reactions that break down fats, proteins, and carbohydrates in order to produce that energy. Although oxygen is an essential component for all living things, it also has an unfortunate ability to produce potentially damaging molecules called “free radicals.” Free radicals are capable of attacking healthy cells, leading to cell damage and cell death. Other forces that cause free radicals are air pollution, sunlight, alcohol, and cigarette smoke. Although there are many theories attempting to explain the aging process, free radical formation is believed to be a major contributor to skin aging.

     Antioxidants are chemicals that have been shown in a laboratory setting to protect cells by neutralizing free radicals. Common antioxidants are Vitamin A (including the retinoids), Vitamin C (ascorbic acid), Vitamin E (tocopherol), coenzyme Q, and beta-carotene. The claim that skin care products containing these antioxidants assist in skin repair and rejuvenation is not supported by strong scientific evidence.


About Moisturizers:

What is a moisturizer?  

     In simplest terms, a moisturizer is a mixture of chemical ingredients that is designed to hydrate the outer layers of the skin, improve the appearance of the skin, and/or improve the health of the skin. An increase in the water content of skin results in skin that feels softer and more pliable. It is this increased hydration that reduces the appearance of fine lines and wrinkles!

Anatomy of Skin: The skin is the largest organ of the body and has several functions: Receptors in the skin provide sensory information like touch, vibration, and pain. The skin helps maintain a constant body temperature, and is a physical barrier to the elements of the environment, providing protection from bacteria, ultraviolet light, and chemicals. But it is the skin’s ability to create a barrier to water loss that is its most crucial function.

The skin is comprised of the following layers:

  • Epidermis – outermost layer which consists of the following:
  1. Stratum corneum: The most mature non-living skin cells (corneocytes) are comprised primarily of a structural protein called keratin. These cells contain a collection of water-soluble compounds call Natural Moisturizing Factor (NMF.) Cells in this layer are surrounded by a fatty lipid layer making the skin virtually water repellent. These cells continually shed and are replaced by cells in the layers below.
  2. Stratum granulosum: Comprised of less metabolically active cells than the ones below them, these cells produce the lipids that are released into the stratum corneum.
  3. Stratum spinosum: Multiple layers of living polygonal skin cells (keratinocytes) produce keratin and ultimately mature to form the stratum corneum.
  4. Stratum basale (Basal layer): The deepest layer of the epidermis comprised of a single row of cells that divide to form new keratinocytes to replace the ones that are continuously shedding from the skin’s surface.
  • Dermis – comprised primarily of collagen to give strength and flexibility. Also contains receptors for pain and touch.
  • Fat layer (Sub cutis) – helps preserve heat and acts as a ‘shock absorber’ for protection from injury.

Why is it Important to Have a Healthy Skin Barrier?

     Adequate hydration to the skin is essential for skin to maintain its flexibility and plasticity. As discussed above, cells constantly migrate from the bottom layer of the epidermis to the most superficial layer, and finally shed. The enzymes responsible for this shedding (desquamation of corneocytes) are dependent on adequate hydration. When this process is disrupted the skin enters a “dry skin cycle” giving it a rough scaly appearance. Imbalance of the water barrier is characteristic of: conditions like eczema, damage due to ultraviolent radiation, and the aging process.

How does the skin maintain a healthy water barrier?

     The outermost layer of skin, the stratum corneum, is responsible for maintaining the appropriate water content of the skin. This paper-thin superficial layer of skin, comprised of approximately 20 cell layers, is an effective water barrier due to three primary characteristics:

  1. Individual skin cells in the stratum corneum (corneocytes) are surrounded by waterproofing lipids (produced in the stratum granulosum layer) that prevent the evaporation of water from the skin. The most common lipids found in the stratum corneum are ceramides, free fatty acids, and cholesterol.
  2. Collections of water-soluble compounds within corneocytes, collectively called the Natural Moisturizing Factor (NMF), absorb water from the environment and from the lower layers of skin to maintain hydration. NMF is comprised of amino acids such as pyrrolidone carboxylic acid (PCA), urocanic acid, lactic acid and urea.
  3. Protein bridges (called desmosomes) hold the corneocytes together, making it difficult for water to evaporate out of the skin.

When these mechanisms do not function properly and adequate water content is not maintained ‘dry skin’ ensues. Individual cells cannot shed appropriately and dry flaky skin results.


How do moisturizers work?

     The term “Moisturizer” is a generic term used to describe a multitude of skin care product formulations that vary in their ability to hydrate the skin, improve skin health, and improve the aesthetic appearance of the skin. Moisturizers sold in the marketplace today can be classified into four main types based on their ingredients:

  • Occlusive based – These oily substances block water evaporation by providing a film on the skin’s surface and thereby trapping water in the upper most layer of skin, the stratum corneum. The most common occlusive ingredients include petrolatum, mineral oil, vegetable oil, and cetyl alcohol. Although very effective in sealing the skin’s surface, these ingredients are often sticky and greasy, and therefore, less cosmetically appealing. Oil-free occlusives, like silicone and its derivatives: dimethicone, cyclomethicone, and amodimethicone, are also commonly found in these moisturizers. The increase in skin hydration from the use of these occlusive agents hydrates dry and damaged skin, and results in increased skin smoothness and an improvement in barrier repair.
  • Humectant based – Moisturizers containing these ingredients work by attracting water from below the epidermis and from the atmosphere, and drawing it into the stratum corneum. Common humectants include glycerin, urea, pyrrolidone carboxylic acid (PCA), lactic acid, propylene glycol, sorbitol and vitamins. Most often intended for daily use on normal skin, these moisturizers are usually water based and very aesthetically pleasing.
  • Emollients – Moisturizers that contain emollients are designed to make the skin feel soft and appear smooth. These products often provide fragrance rather than increase hydration. Emollient based moisturizers are suitable for daily use on normal skin. Emollients are often lipids and oils that soften the skin and impart a smooth and silky feel. Although emollients are less effective at sealing the skin’s surface from water loss than occlusives, they do have some occlusive ability, and therefore, can improve the appearance of dry flaky skin. Common emollients found in moisturizers include lanolin, cetearyl alcohol and sunflower seed oil.
  • Therapeutic Moisturizers – These formulations are designed to treat dry, damaged, and diseased skin conditions. They contain occlusives for water barrier effects, humectants to draw water into the stratum corneum, and emollients to soften the skin. These moisturizers often contain compounds found in the Natural Moisturizing Factor (NMF) like urea, lactic acid, and/or pyrrolidone carboxylic acid (PCA). In addition, they often contain lipids that mimic those found in the stratum corneum, such as ceramides.  

     Emollient based and Humectant based moisturizers may temporarily improve the appearance of dry skin, but they do very little to repair the skin’s barrier function. Occlusive based and Therapeutic moisturizers are more effective in decreasing water loss through the skin by improving the skin’s ability to hydrate.


Sun Facts:

What is sunscreen?

     Sunscreens are products that help prevent the sun’s harmful rays from reaching the skin’s surface. The sun emits harmful rays that reach the earth’s surface. These ultraviolet rays are divided into two types: ultraviolet A (UVA) and ultraviolet B (UVB) rays. UVA rays are longer wavelength rays (320-400nm) that penetrate deep into the skins surface and are a major cause of skin aging and wrinkling. UVA rays can penetrate through glass windows and are the dominant tanning rays. It is now believed that UVA rays also contribute to the development of skin cancers. Whether exposure comes from outdoor sunlight or tanning parlor salons, UVA rays cause cumulative skin damage. UVB rays are shorter in wavelength (290-320nm) and are predominately the cause of skin reddening, sunburn and skin cancers. These rays cannot penetrate through glass windows. UVB rays also play a role in tanning and contribute to the development of fine lines, dark spots, and wrinkles.

What is SPF?

     SPF stands for Sun Protection Factor. SPF indicates how long it would take for UVB rays to cause an individuals skin to redden when using a sunscreen compared to how long it would take to turn red without sunscreen. For example, if it takes 10 minutes of sun exposure to cause unprotected skin to turn red, applying a sunscreen with SPF 15 would take the skin 15 times longer (150 minutes) to turn red, about 2 1/2 hours. An SPF of 30 prevents 97% of UVB rays from reaching the skin’s surface.

What does “broad-spectrum” mean?

     Broad-spectrum sunscreens provide protection from both UVA and UVB rays. When used as directed, these sunscreens will not only protect against sunburn, but also reduce the risk of skin cancer and premature skin aging. Sunscreen alone cannot protect the skin from 100% of the sun’s harmful rays; therefore, it is recommended to seek shade when outdoors, especially between 10:00 AM and 4:00 PM, and wear a wide-brimmed hat, long sleeves, and sunglasses when exposed to direct sunlight.

What does “water-resistant” mean?

     Water-resistant sunscreen is a product that will maintain its declared SPF protection for a minimum of 40 minutes of water immersion. Products that claim to be water-resistant must state on the front label how many minutes of protection (based on standard testing) a user can expect to get of the declared SPF level while swimming or sweating. Two times will be permitted on labels: 40 minutes or 80 minutes.

Sunscreen vs. Sunblock?

     Sunscreens can be classified into two categories depending on how they prevent the ultraviolet rays from reaching the skin. Chemical sunscreens contain ingredients that absorb the ultraviolet rays and prevent them from penetrating the skin. Each ingredient in chemical sunscreens can only filter a portion of the ultraviolet spectrum so most chemical sunscreens contain more than one active ingredient. Most chemical sunscreens break down after several hours of exposure to sunlight and must therefore, be reapplied frequently. Chemical sunscreens are often colorless and leave an invisible film on the skin after application. Chemical sunscreens are more likely to elicit an allergic reaction than physical blocks.

     Physical sunscreens, most often referred to as sunblocks, are products that reflect and scatter the ultraviolet light. These products contain titanium dioxide and zinc oxide, which physically block ultraviolet radiation (UVR). Physical sunblocks are considered broad-spectrum sunscreens, as they protect against UVA and UVB rays. Physical sunblocks can leave a whitish appearing film on the skin after application but they are much less likely to cause allergic reactions.

FDA Approved Sunscreen Ingredients:

Active Ingredient/UV Filter Name Ultraviolet Range Covered 
  UVA1: 340-400 nm
  UVA2: 320-340 nm
  UVB: 290-320 nm
Chemical Absorbers:  
Aminobenzoic acid (PABA) UVB
Avobenzone  UVA1
Cinoxate  UVB
Dioxybenzone UVB, UVA2
Ecamsule (Mexoryl SX)  UVA2
Enulizole (Phenylbenzimiazole Sulfonic Acid)  UVB
Homosalate  UVB
Meradimate (Menthyl Anthranilate) UVA2
Octocrylene UVB
Octinoxate (Octyl Methoxycinnamate)  UVB
Octisalate (Octyl Salicylate)  UVB
Oxybenzone  UVB, UVA2
Padimate O  UVB
Sulisobenzone  UVB, UVA2
Trolamine Salicylate  UVB
Physical Filters:  
Titanium Dioxide  UVB, UVA2
Zinc Oxide  UVB, UVA2, UVA1


What Do I Really Need?




Recommended Basic Skincare Routine

In the morning:

CLEANSE the face with warm water. The use of a mild facial cleanser will help remove make-up, sebum from oil glands, and environmental dirt.

Note: The use of harsh soap is the most common cause of dry, flaky skin as it removes the lipids and proteins necessary to maintain a healthy water barrier. The use of a mild cleansing beauty bar or lipid free cleanser is optimal for most skin types..

MOISTURIZE the face with a moisturizer that contains a . . .

SUNSCREEN of SPF 30 or higher for daily wear. For outdoor activity: Apply a water-resistant sunscreen with SPF of 30 or higher to all sun exposed areas. (Reapply every two hours with increased activity or swimming.) For individuals with sensitive skin, physical sunblocks (products containing titanium and/or zinc oxide) are recommended. For normal skin, the choice of chemical versus physical sunscreen is a personal preference. Moisturize the body after showering especially in cold dry climates.

Note: Other than sun avoidance, sunscreen application is the single most effective anti-aging preventative.

In the evening:

CLEANSE the face with warm water. The use of a mild cleanser will help remove make-up, sebum from oil glands, and environmental dirt.

MOISTURIZE the face to hydrate the skin. Apply a body moisturizer if the skin is dry especially in cold dry climates.

General Recommendations

  • Fragrance is one of the most frequent causes of contact allergic reactions; therefore, fragrance-free skin care products are recommended over scented products.
  • Physical Sunscreens (also referred to as "sunblocks"), are those containing the ingredients zinc oxide and titanium dioxide.  These sunscreens are less likely to cause skin reactions and are, therefore, recommended for individuals with sensitive skin. 
  • Select products with the fewest ingredients to minimize the chance of allergic reactions.



MYTH: Over-the-counter anti-aging creams (anti-wrinkle creams) can reverse the signs of aging.

TRUTH: NO, they cannot. Anti-wrinkle creams are moisturizers. The “workhorse” of any over-the counter anti-wrinkle cream is its ability to hydrate the skin. As moisturizers, these products increase the water content in the most superficial layers of skin temporarily improving the appearance of fine lines and wrinkles. 
 “Anti-aging” ingredients are added to these moisturizers, which are then marketed as rejuvenating. Because the FDA considers over-the-counter skin care products as having no medical value, efficacy of these claims does not have to be proven. If you are looking for “the fountain of youth” in a bottle, you will not find it in over-the-counter skin care products.


MYTH: Expensive skin care products are more effective than less expensive ones.

TRUTH: NO, they are not. There is NO correlation between the cost of a product and its ability to hydrate the skin. An array of affordable moisturizers just as effective as their expensive counterparts are readily available in local drugstores and supermarkets.


MYTH: I need to use anti-wrinkle creams to look my best.

TRUTH: NO, you do not. Most dermatologists agree that the best anti-aging product available on the market today is sunscreen. Protecting the skin from harmful rays during the day with the application of broad-spectrum sunscreen with an SPF of 30 or higher and sun avoidance is most beneficial in fighting skin aging. In addition, applying a daily moisturizer hydrates the skin giving it a more youthful appearance.


MYTH: Skin care products containing "Natural" ingredients are safer and more effective.

TRUTH: NO, they are not. "Natural" ingredients include herbs, oils, roots, and flowers from plants. These botanically derived ingredients are not incorporated into skin care products in their natural state. Neither crushed up leaves nor pressed mushrooms can dissolve adequately into a skin care product. To be compounded into moisturizers they must be processed and chemically modified thereby losing their original “natural” form. There is little scientific evidence that applying products containing plants extracts is beneficial.