SKIN

 Skin

  As the largest organ of the body, the skin protects against germs, regulates body temperature and enables the sense of touch.  The major layers of the skin include the epidermis, dermis and hypodermis and suffer from many problems including skin cancer, acne, wrinkles and pimples.

  Frequently Asked Questions about Anatomy Conditions and Disorder Care

  Overview

  Three layers of skin on the upper part of the muscle tissue.

  What is skin?

  The skin is the largest organ of the body, made up of water, proteins, fats and minerals.  Your skin protects your body from germs and regulates body temperature.  The nerves in the skin help you to feel hot and cold.

  Your skin, along with your hair, nails, oil glands and sweat glands, is part of the antigmentary (in-TEG-you-MEINT-a-ree) system.  "Antigometry" means the outer covering of the body.

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  Anatomy

  What are the skin layers?

  The skin is made up of three layers of tissue:

  Epidermis, the upper layer.

  Drums, middle layer.

  Hypoderms, bottom or layer of fat.

  What does the epidermis (upper layer of skin) do?

  Your epidermis is the upper layer of skin that you can see and touch.  Keratin, a protein inside skin cells, forms skin cells and combines with other proteins to form this layer.

  Acts as a protective barrier: The epidermis prevents bacteria and germs from entering your body and bloodstream and causes infections.  It also protects from rain, sun and other elements.

  Forms new skin: The epidermis constantly builds new skin cells.  These new cells replace about 40,000 old skin cells that your body sheds every day.  You get new skin every 30 days.

  Protects Your Body: The Langerhans cells in the epidermis are part of the body's immune system.  They help fight germs and infections.

  Provides skin color: The epidermis contains melanin, the pigment that colors the skin.  The amount of melanin you have determines the color of your skin, hair and eyes.  People who make more melanin have darker skin and can become tan faster.

  What do the drums (middle layer of skin) do?

  Drums make up 90% of the skin's thickness.  This middle layer of skin:

  Contains collagen and elastin: Collagen is a protein that makes skin cells strong and elastic.  Another protein found in the dermis, elastin, keeps the skin supple.  It also helps the skin to regain its shape.

  Hair grows: The roots of the hair follicles are attached to the dermis.

  Keeps you in touch: The nerves in the drums tell you when something is too hot, itchy or too soft to touch.  These nerve receptors also help you feel pain.

  Makes oil: The oil glands in the skin help to keep the skin soft and smooth.  The oil also prevents your skin from absorbing too much water when you swim or get caught in a rainstorm.

  Produces Sweat: Sweat glands in the dermis secrete sweat through the pores of the skin.  Sweating helps regulate your body temperature.

  Blood supply: The blood vessels in the skin provide nutrients to the epidermis by keeping the skin layers healthy.

  What does the hypodermis do?

  The lower layer of skin, or hypoderms, is the fatty layer.  Hypodermis:

  Cushioning the muscles and bones: The fat in the hypodermis protects the muscles and bones from injury when you fall or have an accident.

  Connected tissue: This tissue connects the skin layers to the muscles and bones.

  Helps nerves and blood vessels: Nerves and blood vessels in the dermis (middle layer) enlarge in the hypodermis.  These nerves and blood vessels branch out to connect the hypodermis to the rest of the body.

  Regulates body temperature: The fat in the hypodermis prevents you from overheating or overheating.

  What else makes the skin?

  One inch of your skin contains approximately 19 million skin cells and 60,000 melanocytes (the cells that make melanin or skin pigment).  It also includes 1000 nerve endings and 20 blood vessels.

  Conditions and disorders

  What conditions and disorders affect the skin?

  As the body's external defense system, your skin is at risk of various problems.  These include:

  Allergies such as contact dermatitis and poison ivy.

  Blisters

  Insect bites, such as spider bites, tick bites and mosquito bites.

  Skin cancer, including melanoma.

  Skin infections such as cellulitis.

  Itchy skin and dry skin.

  Skin diseases such as acne, eczema, psoriasis and vitiligo.

  Skin lesions, such as moles, freckles and skin tags.

  Wounds, burns (including sunburn) and scars.

  take care of

  How can I protect my skin?

  You lose collagen and elastin with age.  This causes the middle layer (skin) of the skin to become thinner.  As a result, the skin may sag and wrinkle.

  Although you can't stop the aging process, these actions can help maintain healthy skin:

  Apply sunscreen every day (even if you are mostly indoors).  Choose sunscreen with at least 30 broad spectrum sunscreen factor (SPF).

  Do not tan indoors or outdoors.  Tanning damages the skin.  It prolongs the life of the skin and can cause skin cancer.

  Find healthy ways to handle stress.  Stress can make certain skin conditions worse.

  Check your skin and moles regularly to see the changes that may be a symptom of skin cancer.

  Quit smoking and use of tobacco products.  Nicotine and other chemicals in cigarettes and electronic cigarettes accelerate skin aging.

  Use a mild cleanser to wash your face in the morning and at night.

  Shower regularly and apply moisturizing lotion to prevent dry skin.

  Frequently Asked Questions

  When should I talk to a doctor?

  If you have experience, you should call your healthcare provider:

  A change in the size, color, shape or balance of a mole.

  The skin changes like a new mole.

  A cut that the home strip can't close (which can have stitches).

  Severe, burning blisters.

  Symptoms of a skin infection such as red streaks or yellow discharge.

  Unclear skin itching or skin condition.

  A note from the Cleveland Clinic

  As the largest organ of the body, your skin plays an important role in protecting your body from germs and elements.  It keeps your body at a comfortable temperature, and the nerves under the skin provide a sense of touch.  Covering this outer body can lead to serious problems like skin cancer as well as common problems like acne and skin rashes.  Your healthcare provider can offer tips to help keep your skin healthy.