Skin Deep

We know that the cosmetic industry likes to make skincare complicated, which is why a couple of Wilde sisters are going to make it uncomplicated for you. No PhDs required! We know how overwhelming it is to look at shelves upon shelves of cosmetic products and not have a clue where to begin . . . is more expensive better? Does cruelty-free really mean that it’s good for us too? Which brand has the fanciest name?

We get it. It can feel impossible to make a decision, and there have been many times when we’ve thought “F*** this noise! At this point, a glass of wine sounds like it’s probably GREAT for my skin!”

It’s really irritating that we didn’t learn any useful science at school (that we can remember!) so here’s a snapshot of the skin’s structure and what it means.

Join us on a journey worthy of Ms. Frizzle, of the Magic School Bus fame, and dive into some skin deep basics . . .


Skin protects us. It is the largest organ that is part of the integumentary system, which shields the body from damage to muscles, bones and internal organs among many other functions. It covers the entire body and also functions as a defensive wall against pathogens, environmental injury and infection.

Our skin is a vital organ. It supports temperature regulation, prevents water loss and provides insulation. Depending on its location on the body, its thickness varies. We don’t have to be scientists to know that the skin on our feet is very different from the skin on our face, and this variation in thickness is a function of utility.

Skin is composed of two primary layers:

  1. The epidermis, which is the outermost layer, contains keratin

  2. The dermis, which extends right below the epidermis, contains nerve endings, sebaceous glands, hair follicles, eccrine sweat glands and blood vessels.

Photo Credit: National Cancer Institute

Photo Credit: National Cancer Institute


The outermost layer of the epidermis, the stratum corneum, consists of dead skin cells. It is both lipophilic (combines well with lipids) and hydrophobic (water repelling). Skin has a such a low permeability that it is effectively waterproof, which is why we don’t turn into sponges in the bath! Lipids are fats, and fats are found in oils. This is why essential oils are used in massage, and are so nourishing for your complexion.

Cells within the epidermis contain keratin, a fibrous protein that supports hydration by preventing water evaporation, and the lifespan of these surface cells is 2-3 weeks. This is why keratin is often used in cosmetic products to support dehydrated skin. Our skin is driest, and also dead, at its surface, with a water content of 10-25% (our lower epidermal layers contain up to 70% water). Good luck finding a dermatologist who would ever recommend harsh exfoliants! Guess what, our dead skin cells function as a layer of protection . . . remember that the next time you want to scrub and scrub!

The stratum corneum is the main barrier to drug and chemical absorption, which is why its 'bricks and mortar' structure has been closely studied. Hair follicles, and eccrine (sweat) and sebaceous glands develop from the epidermis and extend to the dermis. Below, you can see how the lipids provide an effective layer of insulation that prevent a direct hydrophilic (having an affinity for water) path. This means that oils can penetrate this outer layer, whilst water is trapped below in the dermis where the chemical composition changes. Oils=Hydration.


Photo Credit: European Medical Alliance

Photo Credit: European Medical Alliance


Below the epidermis, the dermis consists of connective tissue composed of the fibrous protein collagen, which is embedded in a ground substance (gel-like substance surrounding the cells). If you look at any anti-aging product, you will likely find various concentrations of collagen. The ground substance that provides a bed for collagen consists of water, ions and complex carbohydrates which help hold the cells together. It also allows oxygen and nutrients to diffuse through the tissue to cells. There are networks of collagen and elastin which provide tensile strength and elasticity, and help to return the skin to its original form after it has been stretched. The skin’s elastic quality is something that lessens as we age. This is why products are so often marketed as being able to ‘improve’ elasticity. The blood vessels within this layer provide nourishment and waste removal, which is why your skincare products will claim to contain many nutrients that will support healthy, youthful skin.

Below the dermis sits a subcutaneous fat layer called the hypodermis. It’s common knowledge that fat is an insulator that can supply nutrients. In this context, the hypodermis is where the base of hair follicles, eccrine glands, cutaneous nerves and blood vessels are located. It is generally considered that a drug or chemical has entered the systemic circulation if it reaches this layer. But, as you can tell, there are many cellular layers and defense mechanisms that prevent drugs or harsh chemicals from entering our bloodstream. It’s also important to realise that the permeability of the skin to some chemicals is helpful for medical purposes. Transdermal absorption of drugs is sometimes necessary (nicotine-patch).


Many myths circulate about which products are beneficial, which are harmful, and to whom. This makes it very difficult for all of us to differentiate between excellent marketing and what doctors would recommend, founded upon credible, scientific research. One of the folktales that has gained cultural power concerns the permeability of our skin. However, with little or no understanding of the structure of the skin, some are easily persuaded that everything applied to our skin enters our bloodstream, whilst others suggest that skin is such an effective barrier that only an open wound would cause cosmetics to enter our bloodstream.


As a Wilde Life movement committed to sustainability and nature-based lives backed by science, our job is to source credible research and share with you information that will educate and inspire. Over the years, we have been shamed by the cosmetic industry, with the expectation that we scrub, cleanse, peel, tone and mask our skin. This is why we have shared with you our Wilde Life Guide so that you can be free to make your own, informed Wilde choices.