Epidermis: The Outer Layer of Skin
The epidermis is the thinnest layer in your skin, but it's responsible for protecting you from the harsh environment. The epidermis has four layers of its own: stratum germinativum, stratum spinosum, stratum granulosum, and stratum lucidum. The epidermis also hosts different types of cells: keratinocytes, melanocytes and Langerhans cells. Keratinocytes produce the protein known as keratin, the main component of the epidermis. Melanocytes produce your skin pigment, known as melanin. Langerhans cells prevent foreign substances from getting into your skin.
Dermis: The Middle Layer of Skin
This is the layer responsible for wrinkles. The dermis is a complex combination of blood vessels, hair follicles, and sebaceous (oil) glands. Here, you'll find collagen and elastin, two proteins necessary for skin health because they offer support and elasticity. Fibroblasts are the cells you'll find in this layer, because they synthesize collagen and elastin. This layer also contains nerves that sense pain, touch, and temperature.
Subcutis: The Skin's Fatty Layer
Reduction of tissue in this layer is what causes your skin to sag as well as wrinkle. This layer hosts sweat glands, and fat and collagen cells. The subcutis is responsible for conserving your body's heat and protecting your vital inner organs.
Collagen and Your Skin
Collagen is found in the dermis and is the most abundant protein in the skin, making up 75% of this organ. This is also your fountain of youth. It's responsible for warding off wrinkles and fine lines. Over time, environmental factors and aging diminish your body's ability to produce collagen and can also break down existing collagen.
Your Skin and Elastin
When you hear the word elastin, think elastic. This protein is found with collagen in the dermis, and is responsible for giving structure and support to your skin and organs. As with collagen, elastin is affected by time and the elements. Diminished levels of this protein cause your skin to wrinkle and sag.
Keratin and Your Skin
Keratin is the strongest protein in your skin. It's also dominant in hair and nails. Keratin is what forms the rigidity of your skin.