The skin, much more than a simple covering
The skin is our body's largest organ. Acting as a barrier against external aggressions and preventing infections, the skin regulates temperature and preserves our internal hydration. The skin is the hero of our body on a daily basis.
Composed of three layers: the hypodermis, the dermis and the epidermis, the skin finds its barrier function in its outermost layer: the stratum corneum (SC).
Mainly composed of dead cells embedded in a lipid structure, this stratum corneum is rich in 20% free fatty acids and 20% cholesterol. This lipid complex is essential for maintaining supple, hydrated and resilient skin.
The vital role of the skin barrier
When this skin barrier is intact, it plays several key roles.
- It prevents excessive water loss (called TEWL – transepidermal water loss)
- It blocks the entry of allergens, microbes and irritants,
- It limits skin inflammation.
However, this balance is fragile. Chemical aggressions (irritants, pollution), climatic variations (cold, wind, dryness), or even certain genetic factors can damage it. As a result, the skin becomes fragile and drier, more sensitive. Conditions such as atopic dermatitis, contact dermatitis, psoriasis, and eczema can then appear, disorders that are increasingly widespread and now well known to the general public.
a) Healthy skin barrier protecting against evaporation, moisture, irritants, allergens and microbial organisms.
b) Skin barrier disruption, decreased hydration and increased pH. A disrupted skin barrier is involved in the pathogenesis of various skin diseases.
c) Oils help repair the skin barrier by rebuilding the lipid structure, improving skin hydration.
Skin Barrier and Plant Oils: A Complete Guide to Healthy Skin
Vegetable oils have many benefits. Composed of different fatty acids, they have multiple actions:
Linoleic acid (Omega 6): the repairer , essential for the reconstruction of lipids
in the SC, linoleic acid:
- strengthens the barrier function
- helps retain moisture
- is beneficial for dry, sensitive or eczema-prone skin
You can find linoleic acid in the following amounts in organic oils of: Hemp (45-56%), Nigella (50-65%), Arnica (45%), Argan (40%)
Oleic acid (Omega 9): the penetrating agent , known for its emollient power, the acid
- softens and smooths the skin
- facilitates the penetration of active ingredients into the skin
However, in too large a quantity, it can destabilize the lipid structure of the skin barrier, or even aggravate irritations on sensitive skin.
Find oleic acid in the associated quantities in our organic oils of: Macadamia (55-65%), Argan (43-60%), Calendula (14-40%), Jojoba (5-15%)
Some oils also have anti-inflammatory, antimicrobial and soothing properties, ideal for relieving skin irritation, itching or inflammation.
Good to know: Not all oils are created equal. Some oxidize quickly or are comedogenic (clog pores). That's why it's important to choose oils that are stable, fresh, and suited to your skin type.
At SOWÉ Lab, we rigorously select pure oils, extracted only by a mechanical cold pressing process.
Without solvents, heat, preservatives or perfumes, this process preserves all of the fatty acids, natural antioxidants and waxy residues contained in each oil.
Because respecting your skin means, above all, respecting its most essential nature.
Sources
This article is based on the theses and scientific publications cited below.
- Vaughn AR, Clark AK, Sivamani RK, Shi VY. Natural Oils for Skin-Barrier Repair: Ancient Compounds Now Backed by Modern Science. Am J Clin Dermatol. 2018 Feb;19(1):103-117.
- Berdick, M. The role of fats and oils in cosmetics. J Am Oil Chem Soc 49, 406–408 (1972). https://doi-org.gorgone.univ-toulouse.fr/10.1007/BF02582522
