Skin is our first line of defense against irritants, pathogens and environmental stressors. The epidermis contains sebum (a mixture of lipids, wax esters, fats, and fatty acids) (1), layered with keratinocytes and corneocytes (skin cells in the epidermis) that help seal in moisture while keeping viruses, bacteria, and allergens out. The barrier function is easily disturbed, however. External factors, namely UV exposure and pollution, are well known to compromise the barrier of the skin. In my studies I have discovered that increased cortisol levels and inflammation that occur during psychological stress also contribute to the deterioration of the skin barrier. This blog will focus on the science behind psychological stress and its role in the disturbance of the skin’s barrier function. Don’t worry, I will also tell you what you can do to protect and strengthen it too!
Stress activates two major neuronal pathways: the hypothalamic-pituitary-adrenal (HPA) Axis and the Sympathetic Nervous System (2). In my blog, Aromatherapy & the Stress Response Cycle, I mention the HPA Axis and how high levels of cortisol, our primary stress hormone, can lead to imbalance in the body. To recap, during acute stress the Hypothalamus in the brain sends signals, via the pituitary gland, for the release of corisol by the adrenals. An exciting finding is that various organs in the body, including skin, have their own peripheral HPA mechanism. In this way, the skin “acts like an endocrine organ” (3).
The way in which cortisol is released into the skin is via an enzyme in our Keratinocyte cells. That enzyme is called 11 beta-Hydroxysteroid dehydrogenase 1 (HSDI), or Cortison reductase. It activates endogenous, or naturally occurring, cortisone and converts it to cortisol. HSDI is also activated by UVB light, which then increases cortisol in the epidermis (3). This is one of the factors responsible for delayed wound healing, the disturbance of keratinocyte proliferation, as well the destruction of fibroblasts which are responsible for the creation of collagen and elastin in the dermis (4,5). Stress is a major factor in delayed healing of acne lesions, dull or thick skin, a dehydrated or rough skin surface, and loss of elasticity and density. Psychological stress triggers HSDI and disrupts homeostasis, the delicate balance in the skin.
In addition to the HPA Axis, stress also activates the Sympathetic Nervous System (2). According to the research gathered by A. Garg, “The peripheral nervous system and the skin are intimately connected via free nerve endings that extend to the epidermis” (6). Nerve fibers (and cortisol levels) activate cytokines, or stress mediators in various cells, and have an inflammatory effect. During acute psychological stress the skin’s immune cells are the target of a cytokine assault. Specifically, nerve fibers activate mast cells and cortisol activates Th1 cells to product cytokines (7). Immune cells can become overreactive and cause allergic reactions and itching, and even auto-immune disorders like psoriasis.
The collateral damage of these complex neuroendocrine and immune responses is that they “impair the ability of the skin to respond to environmental challenges” (8). When the skin barrier becomes compromised, it no longer functions effectively. Water loss (called Transepidermal Water Loss, or TEWL) occurs when the barrier can no longer keep water from evaporating. Dehydrated skin with a compromised barrier exacerbates inflammation and disease and can lead to various dermatological disorders. Dermatitis, Psoriasis, Eczema, Acne, Rosacea, and allergic reactions can all become worse when undergoing psychological stress.
If you skimmed through the scientific breakdown in the last few paragraphs, we have finally reached the point of discussing the ways you can improve barrier function! Managing stress addresses the skin from the inside, while treating with lipid rich and anti-inflammatory skin care products supports it from the outside. Looking inward, for individuals struggling with depression, studies show that taking an SSRI decreased the levels of HSDI in the skin (3). Also, created to support a decrease in cortisol and relief from depression, I recommend using my Stony Creek Aromatics’ Restorative Mind-Body Massage Oil. Clinical evidence shows that the barrier function can be improved by inhaling essential oils with a sedative effect (3), in particular the rose, sandalwood, and lavender in this blend. In a zoom class I attended this month with Aparna Ishvari on Abhyanga massage, I learned that in Ayurveda the application of plant oils is understood to “anchor the nervous system” by providing calm to the nerve endings. In a base of Jojoba, Apricot Kernel, Almond, and Avocado, the Restorative Mind-Body Massage Oil can be applied to the full body, excluding the face, every day to support wellness.
As I mentioned in opening, the skin barrier contains lipids, fats, wax, and fatty acids. Healthy skin contains adequate amounts of linoleic acid, according to Brian Goodwin, International Educator for Eminence Organics Skin Care. Linoleic Acid is the omega 6 fatty acid and can be found at high levels in many of my favorite plant-based fatty oils. Looking at a typical analysis provided by Mountain Rose Herbs, some of the fatty oils with the highest amounts of linoleic acid are Grapeseed (containing 65-85%), Evening Primrose (containing up to 72%), Sesame (containing up to 45%), Borage (containing up to 38%), Argan (containing 29-36%), Baobab (containing 24-34%), Apricot Kernel (containing 19-33%), Almond (containing 7-28%), Sunflower (containing 3-20%), and Olive (containing up to 17%). When plant oils are applied to the skin they help to occlude the barrier and seal in moisture. The Eminence Organics Facial Recovery Oil contains Olive and Sesame Oils and have been shown, in third party studies, to increase hydration in the skin up to 53% in 28 days. For those of you that are acne prone, rest assured that the healthy fats in the Facial Recovery Oil plus the antimicrobial, anti inflammatory, anti fungal essential oils of Tea Tree and Clary Sage will improve your condition. Mixed with the Rosehip & Lemongrass Repair Balm, which contains plant waxes, this combination creates a semi-occlusive barrier that helps the skin recover from damage as well as supporting it to prevent further compromise.
To address the constant struggle with inflammation that our skin is undergoing, choosing products that are high in anti-inflammatory ingredients is vital to the strength of the barrier function. One of my favorite summer moisturizers is the Eminence Organics Arctic Berry Peptide Radiance Cream. It contains 4 arctic plants that are rich in anti-inflammatory properties, and peptides to soften fine lines. The Birch Water Purifying Essence contains Reishi mushroom which is an adaptogen that may decrease inflammation and mitigate the skin’s stress response. Lastly, protect your skin from inflammation and increased cortisol with the all-natural mineral based sunscreen, the Lilikoi Light Defense Primer SPF 23.
If my research presented here from the new field of psychodermatology wasn’t exciting enough, consider one more finding that brings this psychosomatic research full circle. There is evidence that “stress-enhanced inflammation (can), in turn, effect the brain since neuroendocrine mediators and cytokines released during inflammation cause a feeling of malaise.” (7) This reciprocal effect shows us that self care is critical for our mental health. Keeping the skin healthy also keeps our brains happy, which is needed now more than ever. The good news is, research shows that inhibiting HSDI may reverse barrier damage (5), so if you need a visualization while you are practicing mindfulness during this social distancing time, try to imagine your nerves becoming calmer and your skin cells stronger, to protect you from this world.
Video of this blog available on my YouTube channel.
1. Pappas A. (2014) Sebum and Sebaceous Lipids. In: Zouboulis C., Katsambas A., Kligman A. (eds) Pathogenesis and Treatment of Acne and Rosacea. Springer, Berlin, Heidelberg
2. Jafferany, M. (2011) Psychodermatology: When the Mind and Skin Interact. Psychiatric Times V 28.
3. Choe S., Kim D., et al (2018) Psychological Stress Deteriorates Skin Barrier Function by Activating 11B-Hydroxysteroid Dehydrogenase 1 and the HPA Axis, Scientific Reports
4. Tiganescu, A. etal. (2014) Increased glucocorticoid activation during mouse skin wound healing. The Journal of Endocrinology 221, 51-61
5. Terao, M., Tani, M., et al (2014) 11β-Hydroxysteroid Dehydrogenase 1 Specific Inhibitor Increased Dermal Collagen Content and Promotes Fibroblast Proliferation, PLOS One
6. Garg A., Chren M. et al (2001) Psychological Stress Perturbs Epidermal Permeability Barrier Homeostasis Arch Dermatol. Vol 137
7. Peters, E. (2015) Stressed skin? a molecular psychosomatic update on stress-causes and effects in dermatologic issues. Journal of the German Society of Dermatology.
8. Bin Saif, G., Alotaibi, H. et al (2018) Association of psychological stress with skin symptoms among medical students, Saudi Medical Journal, 39.