As hard as it is to define beautiful skin, it is possible to say that healthy skin is determined by the healthy structure and proper function of components within the skin. In order to maintain beautiful skin and slow the rate at which it ages, the structures and functions of the skin must be supplemented and protected. If that is the object that you would like to reach, it’s important to know about the skin’s basic anatomy and composition.
|Epidermis||Dermis||Hypodermis (Subcutaneous fat)|
|What is it?||The outermost layers of the skin cells||Fibrous network of tissue that provides structure and resilience to the skin||The deepest layer of the skin|
|Thickness||0.1 – 0.6 mm||0.3 – 0.4 mm|
|Primary purpose|| – Protective shield / waterproof barrier to prevent foreign substances from entering the body
– Limit penetration of the skin
– Limit loss of vital nutrients and water from underlying tissues
– Produces melatonin which functions to filter out UV
| – Structure and support
– Mechanical support network for epidermis providing integrity and flexibility of the skin
– Padding for the body that provides shock absorption
– Storage of nutrients and energy
|How does it work?|| The top part of epidermis – stratum corneum – interacts with the outside environment. This inactive layer of epidermis is sealed with variety of lipids and proteins to form a barrier from the outside environment. Once new layers of cells are produced, the cells of stratum corneum are enzymatically detached.
– Basal layer of epidermis consists of undifferentiated keratinocytes that are supported by contact to the underlying dermis. This is where new cells are produced. There are also melanocytes which produce melanin to create skin pigment and filter out the UV from the sunlight.
– In between the basal layer and the top layer, keratinocytes differentiate to synthesise proteins and secret lipids that will eventually become the new stratum corneum.
The skin we see today was produced 30 days ago. The process of new cell generation will slow down as we age.
| The major components of the dermis work together as a network. This mesh-like network is composed of structural proteins (collagen and elastin), blood and lymph vessels, and specialized cells called mast cells and fibroblasts. These are surrounded by a gel-like substance called the ground substance, composed mostly of glycosaminoglycans. The ground substance plays a critical role in the hydration and moisture levels within the skin
The blood vessels in the dermis help in thermoregulation of the body by constricting or dilating to conserve or release heat. They also aid in immune function and provide oxygen and nutrients to the lower layers of the epidermis. These blood vessels do not extend into the epidermis. Nourishment that diffuses into the epidermis only reaches the very bottom layers. The cells in the upper layers of the epidermis are dead because they do not receive oxygen and nutrients.
The junction between the dermis and epidermis is a wave-like border that provides an increased surface area for the exchange of oxygen and nutrients between the two sections. Along this junction are projections called dermal papillae. As you age, your dermal papillae tend to flatten, decreasing the flow of oxygen and nutrients to the epidermis.
|The hypodermis is the thickest in the buttocks, palms of the hands, and soles of the feet. As we age, the hypodermis begins to atrophy, contributing to the thinning of aging skin.|
Essentially epidermis is made of dead cells that form a layer to protect the rest of the body. How does it apply to skincare? Well, most chemicals cannot fully penetrate this layer of dead skin. As such, if you exfoliate, you shed the dead cells from the surface of the skin thus making it more receptive to the skincare nutrients applied topically. That said, upon thinning the protective layer of the skin, you also make it more vulnerable to the external damage. As such, you have to be extra careful with the quality of products you use and ensure UV –rays protection!
Thank for reading,