Educational Blog Series: How can harsh chemical peels damage your skin barrier?

by | 15 March 2022

What are chemical peels?


Chemical peeling is a skin treatment modality where a chemical substance applied to the skin, causes controlled destruction of the epidermis, with or without parts of the dermis. The goal of a chemical peel is to support skin regeneration and tissue remodelling. 


Chemical peeling modalities are used to treat a variety of skin concerns such as:


  • Congestion and acne
  • Hyper & hypo pigmentation (photodamage)
  • Melasma
  • Sebaceous filaments (mistaken as comedones)
  • Actinic keratosis
  • Superficial and deep scars
  • Wrinkles
Chemical peels are commonly classified based on their depth of skin penetration into superficial, medium, and deep peels. The factors that affect the depth of peeling and thus the degree of its therapeutic effects include the chemical properties used, the application technique, pH value and the skin type and condition being treated.


In this blog, we will explore the different chemical peel depths and risk factors associated with potential long-term use. This blog is not to shame chemical peels, but instead, to give an educational insight as to HOW they actually work on a cellular level, and why they can cause damage to your skin barrier.


But first, let’s have an overview of the barrier function of the skin, and why the skin as a living, breathing organ, is so important to be preserved at ALL TIMES!


Skin as the first physiological barrier of the human body, is the body’s largest organ and encounters the outside environment. Our skin not only prevents damage from external factors such as UV radiation, pollution and microorganisms, but it also prevents loss of moisture and nutrients, and therefore, plays an essential role in protection and defence. 


Our skin is designed to create the skin barrier defence systems, and these defences compromise of many intricate cells and systems in order to maintain homeostasis (balance). Damage to the skin barrier can cause skin problems and concerns such as dryness, poor desquamation (skin cell turnover) as well as wrinkle formation, and may even lead to skin diseases, such as atopic dermatitis, contact dermatitis, and psoriasis.


Skin has the ability of reflecting changes in other cells and systems of the body. Understanding and appreciating this synergy between cells and supporting defence systems, is vitally important when it comes to treating the skin, and finding the leading causes as to why a skin condition or concern is presenting. Perhaps someone’s skin is compromised because of years of subjecting it to the use of harsh chemical peels? 


Let’s now explore the different peel depths beginning with “superficial-depth peels.”


Superficial-depth peels exfoliate the epidermal layers down towards the spinosum layer without extending beyond the basal layer (see image for clarification). Superficial peels exert their chemical actions by decreasing corneocyte adhesion (the cells that make up the outermost layer of the skin), while at the same time, increasing collagen and elastin in the dermis. 



Hang on a minute… but, isn’t this a good thing if collagen and elastin is being stimulated? 


What we mistakenly tend to forget is that skin is an immune-sensitive organ — not a piece of wood that should be constantly peeled away. The skin’s primary role is to defend and protect you, whilst balancing temperature and regulating trans-epidermal water loss (TEWL). Chemical peeling increasing TEWL and allows for a greater risk of potential allergen priming within the skin, not to mention, the continual removal of the epidermis may invoke skin sensitivity overtime due to a decline in immune-competent cells, such as Langerhans cells.


These Langerhans cells act like watchful soldiers; constantly patrolling and protecting the individual from invading microorganisms. Langerhans cells constitute more than 25% of the skin barrier defence systems of the epidermis, and can leave the epidermis entirely if they are repeatedly exposed to chemical burns or aggressive peeling modalities. This would mean the skin would become increasingly sensitive to all sorts of external factors, as the immune system is impaired due to the loss of important lines of skin barrier defence.


The most common side effects using a superficial chemical peel include mild irritation, erythema (redness) and peeling of the skin.


As professional therapists, we explicitly tell our client’s to be consuming good quality Omega 3/6 and to be taking the right quantity ratio of these EFA’s to support the health of the skin. Superficial-depth peels remove the viable layers of the epidermis, but aside from that (if that wasn’t enough), what else is stored within the epidermis? Our Vitamin D3 converted over from UVB and the EFA’s you have been consuming to support your skin!


This begs the question: “Are the EFA supplements you’re taking being counteracted because of the use of a chemical peel?”


Let’s now take a look at medium-depth chemical peels…


Medium-depth peels penetrate the epidermis and reach the upper papillary layers of the dermis, where this layer is responsible for providing a gateway for the active and passive transfer of nutrients and oxygen into the epidermis. In other words, we have REMOVED the epidermis and impacted the upper layers of the dermis (see image for clarification). 



The wound healing response because of this, will result in the recruitment of red blood cells, platelets, infection-fighting white blood cells, metabolic enzymes amongst other cells and systems. Because the epidermis has been removed entirely, there is a certain amount of trauma that occurs within the dermis. This will involve fibroblast stimulation and recruitment (the cells that make collagen, elastin, and hyaluronic acid), combined with increased blood circulation to react to this trauma, resulting in a plumper dermis. 


Now why would this be a bad thing if we are achieving the results of a plumper dermis?


Immediately after a medium-depth chemical peel, the skin may be swollen and can feel tight as a response of wound healing. During the wound healing process, growth factors (GF) are released to support tissue remodelling and repair. GF’s are protein molecules that encourage cells to differentiate, proliferate and grow, however, the wrong GF’s released due to abaltive trauma may result in potential scar tissue formation; which in some cases, has been reported several months after the use of a medium-depth chemical peel.


Medical practitioner’s and skin treatment therapists outside the Corneotherapeutic industry, peel for the penetration of actives and to treat a variety of skin concerns. Skin conditions like pigmentation and ageing make up a large portion of our clients’ concerns, and the topical active ingredients required to make changes to these skin conditions, are often in the vitamin and the coenzyme families, however, the area of the epidermis and dermis to be affected by these actives is below the epidermis — hence the need to chemically ablate the epidermis away.


What are the long term risk factors associated with this? What about increasing the risk for the development of potential skin cancers? After all, you have removed the protective barrier function of the skin that protects you from UV radiation! Doesn’t make a lot of sense now, does it?!


The benefits of working WITH Corneotherapy and a Corneotherapeutic range such as dermaviduals, is that Corneotherapists do NOT have to chemically peel in order to get actives in and below the epidermis, because we have a physiological delivery system that mimics the skin’s structure and function in order to deliver the actives to where they need to go, safely.


Not to mention, the skin is maintained at ALL TIMES which is the foundation and principle methodologies of Corneotherapy.


Let’s now take a look at deep peels


Deep chemical peels penetrate the mid-reticular dermis (see image from clarification). They are the deepest and most aggressive types of chemical peels with a longer healing time than other types of chemical peels. 



Below are some of the risk factors and side-effects to be aware of before one should even consider inflicting this level of trauma to the skin:


  • Post-inflammatory hyperpigmentation (PIH) is a risk and is more likely to occur with client’s who have pre-existing pigmentation problems. Deep peels are not suitable for individuals with darker skin tones as they have a bleaching effect, even lightening fair skin.
  • There is a higher risk of infection. Why? The epidermis and major parts of the dermis have been removed. During the first week, facial movements will be limited and the perioral tissue (i.e., tissue area around the mouth) can crack and develop wounds so clients are generally advised to limit facial movements by ingesting a liquid diet through a straw.
  • The skin may ooze fluid during the wound healing process.
  • Client’s can expect severely swollen, red and uncomfortable skin for at least 2-3 weeks (client depending).


This is out of the scope of a non-medical related skin treatment professional because of the adverse potential of severe side effects.


To summarise, many skin treatment modalities involve chemicals, heat, light or electrical impulses. All of which if not controlled, can burn or scar the skin. Practicing Corneotherapists around the world look for the leading causes as to why a skin condition or concern is presenting, and then link the appropriate skincare products and modalities to the cells and systems affected — this is to ensure long-term that the defence systems of the skin are well functioning and preserved, in order to maintain protection and immunity for host defence.