The Suspicious 6: Our Unique Philosophy
The Suspicious 6: Our Unique Philosophy
AUGUST 31, 2021
There will always be ingredients that we choose to avoid based upon our personal experiences and preferences.
Our one-of-a-kind philosophy on the Suspicious 6, on the other hand, is driven by science and supported by research. Among the Suspicious 6 are the most common skin sensitizers (which lead to symptoms like inflammation), with fragrances, dyes, and essential oils being the worst offenders. This is widely accepted in scientific literature.
What we know about skin aging, skin healing, and conditions like acne has evolved from our increased understanding of skin’s response to irritation. It is also widely understood that anything that increases inflammation worsens concerns such as acne (an inflammatory condition), sun damage (also an inflammatory condition), and uneven skin tone and texture (both of which are promoted and worsened by inflammation). [1,5,6,7]
Irritation and inflammation reduce the skin’s ability to heal while also decimating the skin’s chief support substances (collagen and elastin) and decreasing vital substances in the skin’s acid mantle, such as ceramides, hyaluronic acid, and antioxidants. Exposure to ingredients that irritate and inflame the skin leaves it more vulnerable to damage by environmental stressors, like sun, smoke, and pollution. [2,3]
Environmental irritants trigger inflammatory processes that lead to cumulative damage within skin. The result is a deterioration of collagen and elastin, impaired healing, and even greater detrimental effects of environmental free radical damage. [5,6,7,13,26,37]
The effect of inflammation on skin is cumulative—whether you’re showing signs of irritation or not—and repeated exposure to irritants contributes over time to a weakened skin barrier, slower healing (including of red marks from acne), and an uneven complexion. [5,2,7,25,38]
Removing substances known to cause irritation and inflammation will not only reduce unwanted skin behavior but be beneficial to the overall and continued health of skin.
Inflammation can also be at the root of many of the “skin types” that we identify with. For example, irritation can trigger nerve endings in the pores that in turn trigger the production of androgens, hormones that increase oil production. [3,4]
Since acne is an inflammatory disorder, reducing inflammation will reduce breakouts. But if skin continues to be irritated, inflammation will also continue, worsening breakouts as well as delaying their healing. [3,4,21,22,23,24]
The primary reason for chronically dry skin is an inability to maintain moisture levels in the skin. Inflammation and irritation disrupt the skin’s ability to hold on to vital fatty acids, emollients, and other substances that keep it soft and pliable. Over time, the skin’s inability to maintain healthy levels of these substances leads to a dry, cracked, and inflamed skin barrier. [14,15,27]
Based on the science behind this, we believe that removing substances known to cause irritation and inflammation will not only reduce unwanted skin behavior but be beneficial to the overall and continued health of skin. [1,2,3,4,5,6,7,13,26,27,37]
Removing substances known to cause irritation and inflammation will not only reduce unwanted skin behavior but be beneficial to the overall and continued health of skin.
SODIUM LAURYL SULFATE
Sodium lauryl sulfate (SLS) is considered such a comprehensive skin irritant that it’s used as a standard comparison substance for measuring the skin irritancy of other ingredients. In other words, in scientific studies, when researchers want to establish whether or not an ingredient is problematic for skin, they compare its effect to that of SLS. [33]
In amounts of 2% to 5%, sodium lauryl sulfate can cause allergic or sensitizing reactions. [46,47]
Though some may enjoy the feeling associated with using SLS—that squeaky clean feeling—it is most likely an indication that the skin is irritated, thereby worsening skin problems. [16]
It’s also important to note that many cleansers that use harsh surfactants, like SLS, have an alkaline pH (i.e., a pH level of greater than 8.0), which negatively impacts the acid mantle of skin by causing irritation and increasing the presence of bacteria compared to milder surfactants with a pH closer to that of skin (i.e., around 5.5). [17,18,19,20]
ALCOHOL
Formulas that contain alcohol—on an ingredients list, it appears as SD alcohol, denatured alcohol, alcohol denat., grain alcohol, ethyl alcohol, or just plain “alcohol”—reduce the skin’s ability to maintain moisture and hydration levels and can lead to an increase in oil production. [4,3,24]
While alcohol does enhance the penetration of active ingredients, it does this by dissolving and breaking down the vital lipids of the acid mantle—the very substances that keep your skin healthy over the long term. [30]
In fact, after regular and prolonged exposure to alcohol-based formulas, skin’s acid mantle is no longer able to keep water and cleansing agents from penetrating while washing, further eroding the skin’s barrier. [31]
The irony of using alcohol-based treatments for acne or in mattifying products is that the damage they cause leads to an increase in breakouts, enlarged pores, an increase in oil production within pores, and greater inflammation. [21,22,29]
Research has demonstrated that even at low levels, denatured alcohol (ethanol) causes free radical damage in skin. In one study, 3% alcohol (personal care products contain anywhere from 5% to 60% or higher) applied to skin cells in a lab setting over the course of 48 hours led to an increase in cell death by 26% and a reduction in inflammation-fighting cytokines while promoting free radical damage. That damage increased the longer cells were exposed to alcohol. That is, 48 hours of exposure was dramatically more harmful than 24 hours, and that is only a 3% concentration. [32]
FRAGRANCE & DYES
Regular use of products that contain fragrance, whether naturally derived or synthetic, leads to chronic inflammation, which damages healthy collagen production, worsens undesirable skin conditions (dryness, excessive oil production, breakouts), and impairs the skin’s ability to heal. [5,6,10,11,12]
Fragrance and colorants (aka dyes), whether naturally derived or synthetic, are the leading source of allergic reactions to personal care products. [11,36,41]
The reaction can happen immediately or develop over time; sometimes, when several fragranced products are used, the skin reaches a critical tipping point and suddenly reacts, often strongly. [2,5,7]
ESSENTIAL OILS
We know generally about the harmful effects of fragrance, both naturally derived and synthetic, thanks to comprehensive data on the subject (see above). But essential oils are particularly insidious due to their complicated chemical structure and potential to react upon exposure to both UV light and oxygen, compounding their potential to harm skin. [10,11,28,29,34,35,36,39,40,41]
This is due to the presence of a class of ingredients known as furanocoumarins (psoralen) and coumarins, which are primarily responsible for what’s known as a phototoxic reaction that occurs when skin is exposed to the sun. The result can leave skin discolored. [42,43,44,45]
CHEMICAL SUNSCREENS
The term “chemical sunscreens” refers to multiple active ingredients that provide varying degrees of protection against UVA and UVB sun rays, depending on how they are combined and stabilized. In the United States, avobenzone, oxybenzone, octocrylene, octinoxate, and octisalate are all common examples. [50]
We avoid this class of sunscreen actives because many people find them to be irritating, particularly when used around the eye area. As noted here, irritation is problematic for all skin, but it’s especially so for people with skin disorders, like rosacea or eczema. [5,6,7,48,49,50,51]
SILICONES
We avoid silicones due to their potential to “entrap” active ingredients, thereby reducing their bioavailability, and because we prefer alternatives that offer skin a more comprehensive benefit. We have found that this approach is preferred by our customers, many of whom have cited the presence of silicone as detrimental to their skin (provoking breakouts and unpleasant aesthetics).
CITATIONS
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[35] Yasui Y, Hirone T. Action spectrum for bergamot-oil phototoxicity measured by sunburn cell counting. J Dermatol. 1994;21(5):319-22.
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