The Skin – What is it and what is it made of?
The epidermis is the outer layer of the skin which we can see. It varies in thickness and colour depending on the skin type. The epidermis is thinnest on the eyelids (0.05 mm) and thickest on the palms and soles of your feet (1.5 mm). There are 5 epidermis layers called stratum basale,spinosum,granulosum, licidum and corneum. The bottom layer stratum basale, has cells shaped like columns which push cells up into higher layers. The cells move upwards and eventually reach the higher layer, stratum corneum, where they flatten and die. These skin cells usually shed every two weeks.
The dermis layer lies below the epidermis and also varies in thickness depending on the location on the body. On the eyelid it’s 0.3 mm thick and 3 mm on the back. The dermis is made of three different types of cells – collagen, elastic tissue and reticular fibers. There are two layers in the dermis that contains these three tissues – the papillary and the reticular layers. The upper papillary layer has a thin arrangement of collagen fibers. The lower reticular layer is made from thick collagen fibers parallel to the skin’s surface. The dermis is where our hair follicles, sebaceous (oil) glands, some nerve cells and blood vessels are situated. The blood vessels and nerves run through this layer transmitting feelings of pain, itchiness, temperature, touch and pressure.
The third skin layer, the subcutaneous layer, is made of fat and connective tissue where larger blood vessels and nerves run through. This skin layer is very important in regulating the body and skin temperature. This is where dimpling of the skin is caused by cellulite. The connective tissue in this layer can pucker causing the fat cells to group together in certain areas, giving the appearance of orange peel skin.