The skin is what shields the human body from our external environment, and it's the body's largest organ, with a total area of about 20 square feet.
As your body's shield, it provides various functions such as protection from microbes and irritants, helping to regulate body temperature, and giving you your sensation of touch. It is, therefore, no wonder, that a healthy and intact skin is important for a person's general well being.
The skin’s composition
The human skin can be divided into three different layers with very distinct composition and properties.
The epidermis is the outermost layer of the skin, and the part of the skin that is in direct contact with the external environment. This outermost layer of epidermis is also called the stratum corneum, and is composed of mature dead skin cells called corneocytes that provide a waterproof barrier.
Within the epidermis, there are also specialised cells called melanocytes. These cells are responsible for pigmentation due to their production of melanin. In the very bottom of epidermis, new skin cells are produced by mitosis, these cells undergo a maturation process until they reach the stratum corneum as corneocytes and eventually flake off.
The lifecycle of skin cells is about 28 days, but skin disorders like psoriasis accelerate this process giving the skin its characteristic patches.
The middle layer of the skin is called the dermis. This layer is where the sweat glands are located and so it's responsible for temperature regulation. It’s also in the dermis that hair follicles, nerve endings, and blood vessels are located, along with small oil producing glands which make the epidermis smooth and waterproof. Some people have over-productive oil glands giving them an oily skin, which often leads to pimples.
The third and deepest layer of the skin is called subcutaneous tissue or hypodermis, and is mainly made up of fat and connective tissue. It’s responsible for connecting the dermis with muscles and bones through specialised tissue.
Blood vessels and nerves from the dermis in this layer are distributed to the rest of the body in an organised manner, thereby connecting the body and the skin to work together in response to stimuli. Fat is also stored in this layer, serving as a protection to bones and muscles, and insulation against the external temperatures.
So as you can see, the skin is much more than just a shield for the body. It is responsible for a number of complex and connected processes with the rest of your body that keep your overall well-being in check. It is therefore a good idea to treat your skin with the utmost respect, and in turn, it will take care of you.