All
[3 Articles]

What SIHA avoids when it comes to skincare

Vol 12 Laura Roodhouse

SIHA’s skincare philosophy focuses on strengthening the skin's natural barrier, and any additives such as the below can be counterproductive by causing inflammation and disrupting the Stratum Corneum’s natural function to protect and repair.

Below is a summary of what you won’t find in our stocked products from brand partners:


Artificial fragrances and colours

Fragrances, even those considered hypoallergenic, can cause skin sensitization in some individuals, leading to issues such as contact dermatitis upon repeated exposure. Many fragrance molecules are also small enough to penetrate the skin, potentially causing irritation and inflammation to the dermal layers. 

Perfumes and colours serve no functional purpose in skincare; added primarily for aesthetic reasons, so while they might make a product more appealing to some, they can be detrimental to skin health and compromise the skin’s natural barrier function, so best left out of formulations.


Artificial preservatives

Typically these synthetic chemicals are added to skincare products to prevent the growth of bacteria, mold, and other microorganisms, thus extending a product's shelf life. However, artificial preservatives are generally considered detrimental because they can disrupt the skin’s natural barrier function and microbiome. Many artificial preservatives can negatively impact the skin's natural bacterial flora, potentially leading to imbalances and increased susceptibility to infections or irritation. Even if not allergic, some preservatives can cause irritation and dryness, particularly in individuals with compromised skin barriers.

SIHA’s products leave out preservatives, with packaging that has the appropriate shelf life for their topical application.


Emulsifiers & surfactants

Emulsifiers and surfactants both help create stable mixtures (i.e. blending oil and water). From a corneotherapy perspective, emulsifiers and surfactants in skincare can be detrimental because they disrupt the skin's natural barrier function, potentially leading to dryness, irritation, and increased sensitivity. These ingredients can cause a "wash-out" effect, stripping the skin of its essential lipids and natural moisturizing factors (NMF). Basically, when the skin comes into contact with water, emulsifiers can cause the skin's own protective substances (lipids and NMF) to be washed away, leading to dryness and dehydration. Emulsifiers, especially those found in conventional skincare creams, can penetrate the stratum corneum (the outermost layer of skin) and disrupt the chain-like lipid structure, which we know to be crucial for maintaining skin barrier integrity.

Silicones

Silicones are known for their occlusive properties, meaning they create a film on the skin that can slow down transepidermal water loss (TEWL). While this can provide a temporary sensation of hydration, the barrier formed on the skin's surface can also prevent the absorption of beneficial ingredients from other skincare products and trap dead skin cells, sweat, and other debris from natural excretion, potentially leading to clogged pores and breakouts. In contrast, corneotherapy methodology prioritizes using ingredients that mimic the skin's natural lipid structure and allow for a healthy level of moisture exchange.

Sulfates

Sulfates, particularly Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES), are strong surfactants (they help to foam and lather) that can strip away the skin's natural oils and lipids, leading to dryness, irritation, and potentially even inflammation. This disruption of the skin's barrier can make the stratum corneum susceptible to external aggressors and impair its ability to retain moisture. Sulfates, with their strong cleansing properties, can break down this outermost barrier, leading to increased water loss (transepidermal water loss or TEWL) and making the skin more vulnerable to damage. 

Parabens

Parabens, especially when used in high concentrations or on damaged skin, can penetrate the stratum corneum.
This disrupts the chain-like lipid structure and compromises the barrier function, leading to increased transepidermal water loss (TEWL) and making the skin more susceptible to irritants and allergens. 

While some regulatory bodies consider them safe at certain concentrations, parabens are also  known endocrine disruptors (chemicals that interfere with the body's hormones) and can potentially exacerbate existing skin conditions like eczema and psoriasis. 


Petrochemicals

Petrochemicals like mineral oil and petrolatum, while providing an initial barrier to moisture loss, can impede the skin's natural repair processes and create a dependency, where the skin feels dry when the product is not constantly used. 

Additionally, the barrier created can prevent the skin from effectively shedding dead cells and absorbing essential nutrients, hindering the skin's natural renewal process. By interfering with the Stratum Corneum’s natural processes, petrochemicals can weaken the skin barrier, making it more vulnerable to external aggressors like allergens, pollutants, and pathogens. 


PEGs

PEGs (polyethylene glycols) are generally avoided in SIHA’s skincare due to their potential to disrupt the skin's barrier function and increase the penetration of other ingredients, some of which may be harmful. While PEGs are often used as moisturizing agents and penetration enhancers, similar to the above they can compromise the stratum corneum, the skin's outermost layer, the barrier we know is crucial for protection and moisture retention.


Phthalates

Phthalates, often used as plasticizers in cosmetics, can weaken the stratum corneum by interfering with the lipid structure and impacting the skin's ability to retain moisture. If you’ve read this far, you know when the skin barrier is weakened and you get trans-epidermal water loss (TEWL), it becomes more vulnerable to irritants, allergens, and pathogens, leading to redness, itching, and inflammation. This can exacerbate existing skin conditions rather than help treat them. 


What ingredients do we favour instead?

Corneotherapy advocates for using skincare products with ingredients that are similar to those naturally found in the skin, like ceramides, fatty acids, and cholesterol.