Let’s talk about the basics of skin knowledge.
Normal skin surface PH is between 4 and 6.5 in healthy people, though it varies among the different areas of the skin. The skin is also protected from bacteria and fungal infections and surface contaminants by the acid mantle. The acid mantle is a thin, film-like barrier on the outermost layer of the skin. The acid mantle contains lactic acid, amino acids from sweat, free fatty acids from sebum (an oily substance secreted by sebaceous glands via the hair follicles), and amino acids and pyrrolidine carboxylic acid from the cornification process of skin. Cleansing the skin with alkaline soaps or detergents can disturb the acid mantle.
Our skin is the largest organ of the body and acts as a barrier against the environment, pathogens, and dehydration.
The skin has seven functions:
Skin is also composed of two main layers: the epidermis (outer layer) and the dermis (inner layer and the thickest)
The Epidermis is divided into five layers of cells
Stratum corneum – this layer is composed of dead keratinized cells
Stratum lucidum – clear layer, this layer is found in areas where the epidermis is thicker
Stratum granulosum – this layer is composed of 1-5 sub layers and is believed to help with keratin formation
Stratum spinosum – this layer is the “prickly layer” stabilizes support to the skin
Stratum germinative or basal – the deepest layer which determines skin color and protects the sensitive dermis from UV light.
The Dermis is the thickest layer of the skin. The dermis anchors the skin to the body and contains sweat glands, hair follicles, nerves, and blood vessels. It also contains the sebaceous glands, which secrete sebum and lubricate the skin. The major proteins found in the dermis are collagen and elastin. Collagen gives skin its tensile strength, while elastin provides the skin with elastic recoil. This characteristic prevents the skin from being permanently reshaped. The dermis is divided into two areas: the papillary dermis, which contains capillaries for blood flow, and the reticular layer, which is compromised of thick collagen fibers. The dermis also contains the receptors that sense pain and pressure.
Beneath the dermis lies subcutaneous tissue, which attaches the skin to the underlying structures. Subcutaneous tissue contains fat, connective tissue, blood vessels, lymphatics, and nerve endings.
***Stay tuned for next Skincare Beyond the Basics – Part II
We will be talking all about Collagen & Elastin!!***