Save Your Skin: Why Your Skin Is Important to Your Health
Our skin is our body’s first barrier of defense. It protects us from the elements and keeps potentially harmful disease-causing microbes out while keeping fluids in to prevent dehydration. Skin also helps regulate body temperature through a process called thermoregulation. Near the surface of the skin, small blood vessels called capillaries enlarge when our blood gets too warm to help it cool down.
Skin also is key in our ability to sweat, another critical component of thermoregulation. In its role to aid homeostasis (our body’s ability to maintain biological stability), glands deep in our skin layer secrete sweat – which is mostly water and a little salt – when our body temperature starts to rise above normal.
Like our kidneys and renal system, sweat may also play a minor role in excreting toxins, metabolic waste and excess micronutrients through sweat evaporation from the skin’s surface, according to limited research.
To understand the importance of skin’s function to our health, it helps to know how each of the three layers that constitute our skin function.
The hypodermis, also known as subcutaneous tissue, superficial fascia and subcutis, is the deepest layer of skin lying closest to our muscles, made up of connective tissue and fat. Its primary function is to protect our internal organs from damage by helping to absorb shock, insulate our body from the cold and support overall skin structure.
The middle layer is called the dermis, which itself has two parts: The papillary dermis and the reticular dermis.
The upper papillary dermis contains most of the blood vessels in our skin which reside in loose connective tissue. The thick lower reticular dermis is the powerhouse portion containing sweat glands, hair follicles, nerves, fat cells, more blood cells and lymphatics, the system of vessels that return colorless lymph fluid back to the bloodstream and help protect us from infection. This is all surrounded by an interwoven net of collagen and elastin fibers.
In combination, these two parts of the dermis help protect and support the structure of our skin and aid with sensation and thermoregulation. They balance heat loss with heat generation to maintain our core body temperature.
The outermost skin layer is the epidermis, which contributes to our skin tone as well as provides a highly effective waterproof external barrier. This barrier has a dynamic homeostatic self-regulating capacity to help maintain the overall internal stability of our body and protect us from potentially harmful and changing external environments, scientifically known as “obnoxious stimuli.” Disruption of this epidermal homeostasis causes our skin health to deteriorate and can result in a number of skin diseases, including psoriasis and dermatitis.
The epidermis is the body’s major pathway for vitamin D, which helps convert sunlight into this essential vitamin. The epidermis also features a semipermeable membrane that functions to maintain appropriate moisture levels within the body. And where our skin is thicker, for example on the soles of our feet and palms, the epidermis itself consists of four or five layers of complex cells with different functions, from shielding us from UV exposure to protecting us from microbial diseases.