Skin Barrier Science
The 3 Defense Layers of The Skin Barrier
The microbiome is an ecosystem found at the surface of the skin that acts as a crucial clean up mechanism. Everyone’s microbiome is as unique as their DNA and fingerprints. It’s genetic makeup consists of many microbes – bacteria, fungi, protozoa, and viruses- which are really just exosomes of cells and come from within our own body. The amount of genes in all the microbes in an individual’s microbiome is 200 times the number of genes in the human genetic makeup.
On healthy skin, there is a mutually beneficial relationship between the skin microbiome and the skin barrier with a delicate equilibrium. When disrupted, the microbiome’s barrier functions can fail, leading to an altered pH, toxins invading which can lead to “infection” which is really bacteria showing up as the “clean up” , a decrease of peptides, and an increase in inflammation (due to a toxic terrain) the body amounts an inflammatory response to clean up. Each microbiome is unique, varying with age, location on the body, and gender of the individual.
Our microbiome should be largely undisturbed, and nourished and “fed” with pre and pro biotics, like the oils , “dead cells” of our skin, sweat, and even soil. The oils, acids, plants, minerals, and cultures of our skin barrier line also help as Well, while You are cleaning up a toxic terrain or Needing extra nourishment or protection. When our terrain is clean, our own balanced body oils and cells feed it without causing infection, eczema, or rashes. We can also help create an environment for it to thrive by using oil cleansers, avoiding any antibacterial products, and using a “less is more” approach to caring for our skin with minimal washing, allowing our skin to be a little dirty!
The microbiome plays a role beyond the health of our skin- it’s crucial for cleaning up toxic waste present on our body before entering our body. Think of your microbiome and immune system as a complex detox system rather than an army fighting invaders- it’s instead “breaking them down”. It can influence the clean up response in our body by alerting to the presence of toxin invader so bacteria and clean up cells can show up at the site within the body if needed. A balanced diverse microbiome supports many of the processes that the skin and body needs to stay healthy and resilient.
This microbiome is destroyed by the modern approach to hygiene: tap water, over washing, soaps (even natural), oxidized skincare products, application of alkaline substances, hot water, exfoliation, antibiotics/antibacterial creams, makeup, environmental pollutants, and is affected internally as well by the foods we nourish (or poison) ourselves with, toxins, and our emotional, mental, and spiritual state.
**Updated to reflect my current inner standing of terrain theory. There are no “good or bad bacteria” there are just bacteria that show up for various jobs. Being at the scene of the crime does not make one guilty, I.e like the fireman at a fire. It is crucial to innerstand that bacteria does not cause acne, it creates healthy skin, and breaks down toxins, cellular debris, and even excess hormones. They play whatever role the body needs them to to try to maintain healthy skin, and the more toxic and undernourished your terrain is the more visible this will be (in the form of acne, eczema, psoriasis, saggy skin, wrinkles, fine lines, age and sun spots.
Directly below the microbiome, the acid mantle is the secret to a healthy plump glow. It’s a mixture of sweat, sebum, water, dead skin cells, lactic acid, urocanic acid, fatty acids, and pyrrolidine carboxylic acid. It’s ideal pH balance should be acidic between 4.5 and 5.5. All soaps have a ph of 7+ and therefore alter our ph mantle- natural soaps even moreso- for example the ph of dr. Bronners is 8-9. The acid mantle helps maintain a healthy balanced microbiome and forms a barrier to keep toxins out of your body.
*A note: certain meds can alter the acid mantle, including antihistamines, chemotherapy drugs (like Tamoxifen), Accutane, diuretics, protease inhibitors, and statins.
**A word on “dead” skin cells, aka Corneocytes, that everyone is obsessed with scrapping off, especially in the western approach to skincare. In the Acid Mantle these cells are flattened, hardened, keratinised cells that have lost their nucleus and their lipid membrane. Essentially laying down and packing themselves in tightly to form ’tiles’, as in the tiles on a roof. Most Importantly— they are not dead! The beauty industry has tried to convince us for years, centuries in fact, that the outer layer of skin is dead. The corneocyte has a vital role to play in protecting the layers below it, just as a roof on a house protects the inside. These cells are also able to communicate to the cells below and relay information via chemical messages from the skin surface to the ‘living cells’ below. Dead cells would not have the ability to communicate! In fact the only dead cells are those that have been shed (naturally as they slough off on their own) and form house dust. Scrubbing our skin, using acid peels, exfoliators, and harsh cleansers all remove this layer of skin, which is vital for overall healthy, glowing, plump, and clear skin. Any form of stripping our acid mantle through soaps, over washing, exfoliation, and using alkaline products on our face causes micro tears or cracks in our skin and dries our skin- leaving it susceptible to toxins entering our body- which will then lead to an overgrowth of bacteria, fungus, or parasites, as they show up to “clean up” the toxic mess. This can display as acne, eczema, psoriasis, etc. (These can also reflect inward malnourishment and toxicity) as the health of our skin is affected by our care of the inside and outside of our body.
Extreme elements such as hot dry weather, cold dry weather, or extremely hot or cold water also affect our acid mantle. We can assist it by washing as minimally as possible, using hydration sprays ph balanced to 4.5-5.5 like our No.2 Mist, and locking it in with our serum oil.
Lipids are diverse compounds that are insoluble in water. They store energy, protect against water loss, and form cell membranes. The extracellular lipid matrix located in the stratum corneum is an essential component of the permeability barrier. The epidermal barrier protects the body from transepidermal water loss, and the entry of external substances. It consists of ceramides – waxy, lipid molecules formed from sphingosine and fatty acid, free fatty acids, byproducts of the metabolism of fat in adipose tissues, and cholesterol- a waxy, fat molecule made by the liver, with ceramides being the essential compound. The lipid bi-layers are the glue that holds the corneocytes together. It comprised of ceramides (40%), cholesterols (20-25%) and free fatty acids (20-22%). Along with Natural Moisturising Factor, which is made up of amino acids broken down from the protein Fillagrin within the corneocyte envelope, the lipid bi-layer structure provides waterproof semi-permeability as well as strength and resilience for the corneocytes, which without the ‘glue’ holding them together be like having a leaky roof.
When all three lines are in tact and performing well, the skin provides both chemical and physical protection from environmental toxins, as well as providing a waterproof suit to regulate temperature, keep us hydrated, protect us from UV damage and increase sun resilience, and stop our inner bits from falling out.