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Being created from coconut oil means Cocamidopropyl Betaine is hydrating for the skin.

While Cocamidopropyl Betaine was believed to be an allergen, a study from 2012 disproved this. It found two compounds in unpure Cocamidopropyl Betaine to be the irritants: aminoamide and 3-dimethylaminopropylamine. High-grade and pure Cocamidopropyl Betaine did not induce allergic reactions during this study.

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.

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

This ingredient is considered safe at present practices of use and concentration and repeated insult patch test with 50% Glycol Distearate on 125 subjects found no evidence of skin irritation, hypersensitivity, or acute toxicity.

Typical use concentrations range from 0.1-10%.

Because it's an ester of stearic acid, it falls into the range that Malassezia likes to metabolize. This ingredient may not be fungal acne safe.

It is also used to make a product more thick.

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

Squalene is also naturally present in olive oil and exhibits moisturizing and antioxidant properties.

The polyphenols in olive oil also show anti-aging promise; one clinical study found a measurable improvement in skin appearance after 30 days of topical serum use.

Just be aware that applying olive oil directly to skin can weaken the barrier and cause redness. One study with volunteers found even people without sensitive skin experienced a significant reduction in stratum corneum integrity and induced mild erythema.

It's best to use this ingredient as part of a carefully crafted formula (instead of putting it on skin directly from the bottle).

Because it has a 2-3 on the comedogenic scale, it is a moderate risk for acne-prone skin. However, the overall formulation of a product matters more than a few ingredients with comedogenic ratings.

This ingredient may not be fungal acne safe because of the oleic and palmitic acid content. These fall within the C11-24 fatty acid range that the Malassezia yeast can metabolize to grow.

Overall, olive oil is a well-studied and nourishing skincare ingredient.

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).

Due to the origins of this ingredient, it is not vegan. Silk is an animal product from silkworms.

Depending on the source, this ingredient can be considered cruelty-free. It is created from left-over cocoons of silkworms. We recommend reaching out to the brand if you have questions about where their hydrolyzed silk comes from.

Tocopheryl Acetate is commonly found in both skincare and dietary supplements.

When exposed to air, these two compounds become strong allergens. This ingredient exhibits cytotoxicity at low concentrations; amounts of 0.25% have been shown to damage skin cells.

A study from Japan found this ingredient caused lavender sensitivity after widespread exposure.

Lavender essential oil has some antimicrobial, antibacterial, and anti-inflammatory properties. However, the cons of this ingredient may outweight the pros.

More research is needed to confirm lavender essential oil's effects when used in aromatherapy.

Lavandula Angustifolia is known as the English Lavender and famous for creating purple fields in Provence, France.

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.

Traditional Iranian folk medicine uses Lavender extract to help treat inflammation.

Lavender extract may have a scent.

It contains linalool, a known allergen. However, lavender extract contains less linalool than lavender essential oil.

Evidence for mint as a "treatment" ingredient is limited and depends heavily on the specific extract type and concentration.

In large percentages, peppermint extract may sensitize the skin.

Allantoin is well-studied for promoting the skin's natural repair process and helping skin look smoother. Comfrey is also rich in antioxidants like Rosmarinic acid and Caffeic Acid.

Research has shown that these compounds work together to help calm redness, protect against oxidative stress, and support overall skin health.

Algae is rich in antioxidants. Antioxidants help fight free-radicals. Free-radicals are molecules that may damage your skin cells, such as pollution.

Algae can also help with soothing and hydrating skin.

Many different types of algae have different benefits.

Antioxidant components in chamomile make it an effective ingredient to help slow the signs of aging. Antioxidants help fight free-radical molecules, or molecules that may damage your skin.

Essential oils from chamomile have been found to improve wound healing due to its antimicrobial properties.

Ancient Greeks and Egyptians used Chamomile to treat skin redness and dryness. Chamomile has also been used to help treat stomach issues.

Lavender extract may have a scent. It contains linalool, a known allergen. However, lavender extract contains less linalool than lavender essential oil.

These compounds protect your skin two ways:

1) They fight off free radicals, or the unstable molecules from things like sun and pollution that age and damage skin.
2) They help calm inflammation by switching off the chemical signals that tell skin to get red and irritated.

Lab studies also suggest that rosmarinic acid may help protect collagen and slow sugar-related damage to it.

The Cosmetic Ingredient Review has concluded rosemary-derived ingredients to be safe when formulated to be non-sensitizing.

Rosemary can occasionally cause allergic contact dermatitis (due to carnosol), so be sure to patch test if you have reactive or fragrance-sensitive skin.

Studies also demonstrate it has antimicrobial activity against acne-related bacteria. A 2017 study found this extract exhibited anti-inflammatory effects.

However, this ingredient does have sensitization potential due to its terpene content. Terpenes are among the most common causes of contact dermatitis.

This is kind of a double-edged sword situation where the same compounds that give it antimicrobial power can also irritate reactive skin.

As a humectant, it pulls water into the skin. But it's a pretty minor moisturizing ingredient compared to other humectants, like glycerin.

Interestingly, it can act as a mild penetration enhancer. One in vitro study on human skin found a 12% concentration upped the absorption of mometasone furoate (a medicinal ingredient used to treat inflammatory skin conditions) up to 7%.

This ingredient is typically used at levels of 0.1-10% depending on the role it's playing.

A patch test study on eczema patients didn't find a significant increase in irritation versus the control group, but the potential for irritation rises at higher concentrations.

This structure lets it bridge oil and water to prevent ingredients from separating and keep formulas stable. It is also the reason it gives cosmetics a creamy feel without the greasiness.

The CIR Expert Panel has concluded this ingredient to be well-tolerated. Human repeated patch testing on the undiluted version has come back negative for irritation and sensitization. On top of that, its large molecule size makes skin penetration unlikely.

Usage concentration ranges from 5% in rinse-off to 1.8% in leave-on formulas.

Because this ingredient is made from stearic acid, it may not be fungal acne safe. Stearic acid is a C18 fatty acid that the Malassezia yeast can substrate.

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.

Due to the large molecule size, this ingredient is unlikely to penetrate skin.

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

As an emulsifier, it helps make oils and oil-soluble ingredients more soluble in water.

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

Glycolic acid removes the top layer of dead skin cells to allow newer and fresher ones to emerge.

AHAs work by breaking down the structural “glue” that holds old skin cells in place. When that buildup is gone, your skin can renew itself more efficiently.

Research also shows glycolic acid stimulates collagen production, helping to firm and thicken the skin over time. This is one of its biggest advantages over other AHAs.

Overall, glycolic acid helps with:

Fun fact: Glycolic acid boosts skin hydration by helping it produce molecules that increase hyaluronic acid naturally.

To work best, glycolic acid products should have a pH between 3-4 (that’s where exfoliation is most effective but still gentle on skin).

The pH and concentration of a product are key to its effectiveness:

It is normal to feel a slight stinging sensation when using glycolic acid. This usually fades as your skin adjusts.

Because glycolic acid has the smallest molecular size in the AHA family, it can penetrate deeper, which enhances its effectiveness but also makes it more likely to irritate sensitive skin.

If your skin is very sensitive or prone to rosacea, glycolic acid may be too strong; in that case, try milder options like lactic acid or a PHA instead.

Recent studies suggest glycolic acid might even help protect against UV damage. But don’t skip sunscreen! Freshly exfoliated skin is more sensitive to the sun.

Glycolic acid is a skincare superstar. It smooths, brightens, hydrates, and firms the skin. Unless you’re highly sensitive, it’s well worth adding to your routine.

Read more about some other popular AHA's here:

The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.

True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).

It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.

Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.

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.

Solvents are used to keep ingredients together in a product. They can help dissolve ingredients to stable bases or help evenly distribute ingredients throughout the product.

Due to its fragrance, Benzyl Benzoate can be sensitizing and may cause contact dermatitis. It is a known EU allergen. We recommend speaking with a professional if you have any concerns.

Benzyl Benzoate can be naturally found in cranberries and peaches.

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.

This ingredient has a scent that is floral, spicy tropical, and citrus-like.