Serum
Serum
American United States
American United States

What's inside

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Humectant, Masking, Skin Conditioning

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

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.

Learn more about Butylene Glycol
Emollient, Humectant, Skin Conditioning

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

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

Learn more about Caprylyl Glycol
Buffering, Masking

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

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:

Learn more about Citric Acid
Cleansing, Emulsion Stabilising

Decyl Glucoside is a plant-derived surfactant and emulsion stabilizer. It is created by reacting glucose with the fatty acids from plants.

Like all surfactants, it works by lowering the surface tension between water and oil. This makes it so that dirt, sebum, and makeup can be lifted off your skin and rinsed away. It also produces a dense and creamy foam.

Because it has a neutral charge, it is compatible with a wide range of ingredients and stays stable across a broad pH range/water hardiness conditions.

Patch testing has shown it to have the lowest irritation potential among common cleansing surfactants (like SLS).

Typical use levels range from 5-20% in rinse-off cleansers.

One thing worth knowing: The American Contact Dermatitis Society named the parent family, alkyl glucosides, "Allergen of the Year" in 2017. The prevalence of allergy is pretty low but be sure to patch test if you've reacted to "gentle" or sulfate-free cleansers before.

This ingredient is fungal acne safe because the fatty alcohol portion of this ingredient is not within the C11-24 chain length that Malassezia can metabolize.

Learn more about Decyl Glucoside
Emollient, Skin Conditioning, Skin Protecting

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

Learn more about Dimethicone
Humectant, Skin Conditioning, Skin Protecting

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

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.

Learn more about Glycerin
Antioxidant

Hydroxyacetophenone is antioxidant with skin conditioning and soothing properties. It also boosts the efficiency of preservatives.

Though naturally occuring in Norwegian spruce needles, this ingredient is usually synthetically created.

This ingredient is not irritating or sensitizing. Recent research also suggests it may have skin-brightening effects through tyrosinase inhibition.

Learn more about Hydroxyacetophenone
Emollient, Skin Conditioning, Solvent

Isohexadecane is added to enhance texture, emulsify, and to help cleanse. It is an isoparrafin. It is a component of petrolatum.

Due to its large size, Isohexadecane is not absorbed by the skin. Instead, it sits on top and acts as an emollient. Emollients help keep your skin soft and smooth by trapping moisture within.

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.

Learn more about Isohexadecane

Polymethylsilsesquioxane is a silicone used as a film forming agent.

When applied to the skin, this ingredient creates an invisible film on the surface. This film still allows oxygen to pass through, but prevents moisture from escaping. This can help condition and hydrate the skin. It also leaves a silky feel when applied.

Polymethylsilsesquioxane has not been shown to clog pores. It has been deemed safe to use up to 55%, but most cosmetics use much less.

If you have concerns about using this ingredient, we recommend speaking with a professional.

Learn more about Polymethylsilsesquioxane

Polysilicone-11 is a film-forming silicone that creates a non-tacky and matte finish on the skin. It's commonly used to improve texture, absorb excess oil, and help active ingredients spread evenly.

Due to its "rubber-like" structure, it stays on the skin's surface instead of being absorbed. On the skin, it creates a flexible layer that enhances wearability and stability.

Emulsifying

Polysorbate 80 is a surfactant and emulsifier. It is used to keep ingredients together, and prevent oils and waters from separating.

It is made from polyethoxylated sorbitan and oleic acid. This ingredient can be found in cosmetics, foods, and medicine. It is water-soluble.

Polysorbate 80 may not be fungal acne safe.

Learn more about Polysorbate 80
Solvent

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin. 

It’s often used to:

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.

Learn more about Propanediol

This long ingredient is a copolymer of sodium acrylate and sodium acryloyldimethyl taurate monomers.

It is used to help stabilize other ingredients and create a thicker gel-like texture.

Emulsifiers prevent oils and waters from separating.

Learn more about Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
Humectant, Skin Conditioning

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Learn more about Sodium Hyaluronate
Skin Conditioning, Solvent

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Learn more about Water

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