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This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.

A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.

Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.

Fun fact: The human body also creates Glyceryl Stearate naturally.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

A double-blind study confirmed that extra virgin coconut oil is as effective as mineral oil for treating very dry skin. Another study found it outperformed mineral oil for mild to moderate atopic dermatitis in children.

Another study from 2018 found that virgin coconut oil can soothe inflammation and boost key skin barrier proteins. Just know this evidence is still only from lab settings and not human trials.

It has also been shown to reduce Staphylococcus aureus, a bacteria that commonly overgrows in people with eczema.

Clinical testing shows very minimal skin irritation and no evidence of sensitization or phototoxicity.

Coconut oil gets flagged as a "fragrance" because it has a natural mild scent (not because it's a synthetic perfume). The European Cosmetic ingredient database also lists "perfuming" as a function of this ingredient.

Just so you know, the term "fragrance" is completely unregulated. Some brands still use botanical extracts or essential oils in their "fragrance-free" formulas, but regulatory databases technically classify these under "fragrance".

Coconut oil has a tiny and useless bit of natural SPF. Early lab studies clocked it around SPF 7-8 but a more recent study found the real number closer to SPF 1.2. It also offers no meaningful UVA protection (SPF only overs UVB rays).

The comedogenic rating of 4/5 means it has a high potential to clog pores; but it's worth noting that comedogenicity is highly individual and ratings cannot predict how an overall formula will behave on skin.

Since lauric acid is the dominant fatty acid, this ingredient may not be fungal acne safe. The Malassezia yeast feeds on fatty acids with carbon chain lengths between 11-24, and lauric acid falls within these lengths (C12).

Unlike other plant oils, jojoba wax doesn't easily penetrate skin. It mostly works in the uppermost layers as an emollient. This just means it forms a light barrier on the skin to help retain moisture.

Formulations with jojoba esters up to 90% reduced transepidermal water loss (TEWL) and increased barrier recovery by 81% (outperforming bisabolol at 47%).

Besides barrier support, the science also suggests jojoba to have anti-inflammatory effects and potential applications for skin infections, aging, and wound healing.

Fun fact: Indigenous cultures have used jojoba as a moisturizer and to help treat burns for centuries.

Fungal acne: The Malassezia yeast is known to metabolize fatty acids in the C11-24 range and jojoba's dominant fatty acid components fall into this range. This ingredient may not be fungal acne safe.

Linoleic acid helps maintain skin barrier integrity and is a building block for the ceramides in your stratum corneum. Notably, people with acne tend to have lower linoleic acid in their skin lipids as well (and this gets worse as acne gets more severe).

Overall, it's a lightweight, fast-absorbing oil that has a long safety track record. Lab testing has found it to be non-irritating for skin or eyes.

The Malassezia yeast can metabolize the fatty acids in this oil to grow; therefore this ingredient may not be fungal acne safe.

Antioxidants help fight free-radical molecules. Free-radical molecules are capable of damaging our cells and other genetic material. Antioxidants help stabilize free-radicals by donating extra electrons. Grape seed extract may help reduce the signs of aging.

The antimicrobial properties of grape seed may help treat acne. However, more research is needed to support this claim.

Grape seed has also been found to help absorb UV rays. Grape seed extract should not replace your sunscreen.

The fatty acids of grape seed oil give it emollient properties. Emollients help soothe and soften your skin by creating a film. This film traps moisture within, keeping your skin hydrated.

In skincare, it is an emollient that dries down to a solid film with water-binding properties. This helps keep skin hydrated and helps reduce transepidermal water loss (TEWL).

A 2026 dermatology review pulls together its broader uses:

Human clinical testing found this ingredient to be non-irritating and non-sensitizing.

Because castor oil contains fatty acids in the C11-24 range, this ingredient may not be fungal acne safe.

At this time, the literature does not support castor oil in regrowing hair. A 2022 systematic review found no strong evidence that it supports hair growth and only weak evidence that it improves hair shine.

Castor oil itself carries "perfuming" and "masking" function tags according to the official CosIng database. This is because of its mild odor and odor-dampening properties.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

Safety-wise, the CIR Expert Panel has concluded it to be safe in cosmetics when formulated to be non-irritating and non-sensitizing.

Free stearic acid is a C18 fatty acid that the Malassezia yeast can substrate, so this ingredient may not be fungal acne safe.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

It can also form a thin protective film on skin. One study found that a formula using this polymer helped slow down how quickly other ingredients (like DEET) were absorbed through skin.

A 2024 study of over 1,300 patients confirmed that sensitization to this ingredient is rare. It is also non-mutagenic and has a clean track record.

Emulsifiers prevent oils and waters from separating.

This ingredient has skin conditioning, anti-inflammatory, and humectant properties. Humectants help hydrate your skin by drawing moisture from the air. This helps keep your skin moisturized.

High percentages of Sodium Lactate can have an exfoliating effect.

Fun fact: Sodium Lactate is produced from fermented sugar.

Isohexadecane is often used in products designed to help oily skin. It is lightweight and non-greasy while helping to moisturize. When mixed with silicones, it gives a product a silky feel.

This property also makes Pentylene Glycol a great texture enhancer. It can also help thicken or stabilize a product.

Pentylene Glycol also acts as a mild preservative and helps to keep a product microbe-free.

Some people may experience mild eye and skin irritation from Pentylene Glycol. We always recommend speaking with a professional about using this ingredient in your routine.

Pentylene Glycol has a low molecular weight and is part of the 1,2-glycol family.

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

The CIR Expert Panel has evaluated the scientific data and found this ingredient to be safe, non-irritating, and non-sensitizing at concentrations up to 5% (it's even approved by the FDA as an OTC eye drop ingredient).

Typical use levels in formulas range from 2-10%.

The CIR Expert Panel has concluded this ingredient to be safe as a cosmetic ingredient.

Since this ingredient is an ester of oleic acid, it may not be fungal acne safe. Oleic acid is a fatty acid that falls into the C11-24 range that Malassezia can metabolize.

Research on a hydrogel with serine confirmed this serine got delivered to your stratum corneum and demonstrated enhanced skin moisturization.

Interestingly serine also helps your skin produce filaggrin, a protein that keeps your skin barrier strong and used to create collagen.

This ingredient can either be derived from an animal product or be synthetically created.

This ingredient is very interesting as a hydrator; most moisturizers are either occlusives, humectants, or emollients. Isostearyl isostearate works through another route named "internal occlusion" by the head researcher.

Isostearyl isostearate nudges the skin's own lipids into a denser, more tightly packed arrangement. Packing the deeper layers of the stratum corneum together more efficiently means less water is able to escape.

This is a barrier-improving mechanism that hadn't been described before and plastic occlusion stress tests confirmed it improved the skin's water-permeability barrier function

Just one thing worth noting from the same review: this ingredient increased the penetration rate of a test drug through excised human skin. Though this ingredient is not classified as a penetration enhancer, it does interact with the barrier rather than sitting totally inert on top.

Fungal acne:
The Malassezia yeast feeds on fatty acids and esters in the C11-24 range. Since both halves of this molecules are C18, it may not be fungal acne safe.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

Reviews of this ingredient have found it to be neither a dermal irritant nor a sensitizer.

Fun fact: Proline can be found in protein-rich foods like meat, fish, eggs, and dairy.

Typical use levels are between 1-5% and this ingredient is considered to be non-irritating by the CIR Expert Panel Review.

Once applied, your skin's glucoside hydrolases breaks it down to the parent fatty alcohol and glucose. This is why this ingredient may not be fungal acne safe.

One study found histidine and carnosine to be a dynamic duo for your skin:

Oral histidine has also been found to help with filaggrin-deficit skin disorders such as atopic dermatitis.

Why is it considered a semi-essential amino acid? This is because adults are able to create it but children must get it from their diet.

Two structures of phenylalanine exist: L-phenylalanine and D-phenylalanine. L-phenylalanine is essential, this means our bodies cannot produce it naturally and we must get it from foods. Our bodies convert D-phenylalanine to neurotransmitters, and D-phenylalanine is found in our bodies naturally.

Some foods that contain L-phenylalanine include eggs, soybeans, beef, milk.

Like other alcohols, this ingredient helps prevent the growth of bacteria. However, its main purpose is to impact a fragrance.

In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).

Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.

Shea butter also contains vitamins A and E which may contribute to antioxidant activity.

While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.

This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.

It's worth knowing sugars are already a natural component of the skin's NMF (natural moisturizing factor) so it's a molecule that your stratum corneum is well-acquainted with.

Just so you know, glucose is hydrophilic (water-loving) and the stratum corneum is a strong barrier to hydrophilic compounds. This just means penetration is slow and most of the action is happening on the surface.

Gram-to-gram, glucose is not as efficient as a humectant as glycerin. This is why you'll likely see glycose paired with stronger humectants for a bigger hydration payoff.

In skincare, glucose is typically derived from corn or other starch sources.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Read more about some other popular AHA's here:

In many countries, coumarin is banned as a food additive. However, it can be found in soaps, tobacco products, and some alcohol drinks.

Plants use coumarins as a chemical defense. Some plants that have coumarins include lavender, tonka beans, and yellow clovers.

Limonene acts as an antioxidant, meaning it helps neutralize free radicals.

When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.

The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.

Naturally occurring Alpha-Isomethyl Ionone may be found in Saccharomyces cerevisiae, or the yeast used to make wine and bread.

The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.

Vanillism is the term of contact-dermatitis associated with the vanilla plant. The sap of the vanilla plant triggers skin irritation, swelling, and redness.

For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.

The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.

For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.

One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.

Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.

Parfum can also be used to mask or cover an unpleasant scent.

The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.