What is the stratum corneum layer of the skin?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)

The stratum corneum is the outermost layer of the epidermis, also known as the skin barrier. It is our first line of defense against the environment.


Dr. Ellen Marmur, MD
There are four epidermal layers, the first of which is the stratum corneum. When you touch your skin, what you're feeling is almost thirty layers of dead keratin cells (a protein that also makes up hair and nails). All these inert cells, called keratinocytes, overlap like thin shingles on a roof, with pores (the ducts for hair follicles and sweat glands) interspersed among them. These tough keratinocytes shed approximately every twenty-eight days, depending on your skin's regenerative process. New cells that are formed in the lowest level of the epidermis push upward to the surface, constantly replacing the old ones. When your skin flakes, what's coming off are thousands of those dead cells. In fact, every minute we shed about forty thousand keratinocytes. 
Simple Skin Beauty: Every Woman's Guide to a Lifetime of Healthy, Gorgeous Skin

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Simple Skin Beauty: Every Woman's Guide to a Lifetime of Healthy, Gorgeous Skin

What if a leading dermatologist just happened to be your best friend and you could ask her anything? DR. ELLEN MARMUR, a world-renowned New York City dermatologist, answers all your questions with...

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.