Humectant, drawing moisture into the skin
Emollient, helping to soften skin
Solvent, dispersing and stabilizing formulas
Preservative booster, enhancing the antimicrobial activity of other preservatives

Allantoin

Skin Conditioning, Skin Protecting, Soothing

Allantoin plays a role in soothing and moisturizing the skin. Because of this, it is often added to products with strong active ingredients.

Some studies have shown this ingredient can promote wound healing with higher concentrations.

Allantoin is derived from the comfrey plant but produced synthetically for cosmetic products to ensure purity.

Learn more about Allantoin

Arginine

Masking, Skin Conditioning

Arginine is an amino acid that is important for human development. Your body uses is it to produce hair keratin and skin collagen.

As a cosmetic ingredient, Arginine has antioxidant properties and can also help repair damaged skin. This ingredient is derived either synthetically or from animals.

Arginine isn't fungal acne safe when used in the presence of other lipids (fats, fatty acids, oils, esters, etc). Oils and fats occur naturally within the skin, so take caution when using Arginine if you're prone to fungal acne.

Learn more about Arginine

Aspartic Acid

Masking, Skin Conditioning

Aspartic Acid is an amino acid that our bodies produce naturally. It is an antioxidant.

Our body uses Aspartic Acid to help build collagen and elastin. It also plays a role in hydrating skin.

Caprylyl/Capryl Glucoside

Cleansing, Foaming

Caprylyl/Capryl Glucoside is an alkyl glucoside. This just means it is creating by reacting alcohol and sugar. It is a cleansing and foaming ingredient.

Caprylyl/Capryl Glucoside helps remove the dirt, oil, and other pollutants from your skin.

Citric Acid

Masking, Buffering

Citric Acid is an AHA derived from citrus fruits (think oranges, lemons, and limes!).

As an AHA, Citric Acid removes the top layer of skin cells from the newer layer of skin underneath. This helps skin to remove dark spots and even out skin tone.

If you spot Citric Acid near the end of an ingredient list, it's likely there as a pH adjuster rather than an active ingredient.

Read more about some other popular AHA's here:

Learn more about Citric Acid

Glutamic Acid

Humectant

Glutamic Acid is an amino acid that is found in all living organisms. Our bodies use this to help nerve cells in the brain communicate with other cells.

In cosmetics, glutamic acid is a famous humectant. It draws water from the air to your skin, keeping your skin hydrated (like hyaluronic acid).

An in-vitro study from 2024 found glutamic acid to play a role in inhibiting inflammation and thus a potential skin-soothing ingredient.

Other studies show it to be have potential wound healing, skin barrier repair, and hair growth properties.

Glutamic acid has poor solubility in water and other solvents.

Learn more about Glutamic Acid

Glycerin

Humectant, Skin Conditioning, Skin Protecting

Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.

A study from 2016 found glycerin to be more effective as a humectant than AHAs and hyaluronic acid.

As a humectant, it helps the skin stay hydrated by pulling moisture to your skin. The low molecular weight of glycerin allows it to pull moisture into the deeper layers of your skin.

Hydrated skin improves your skin barrier; Your skin barrier helps protect against irritants and bacteria.

Glycerin has also been found to have antimicrobial and antiviral properties. Due to these properties, glycerin is often used in wound and burn treatments.

In cosmetics, glycerin is usually derived from plants such as soybean or palm. However, it can also be sourced from animals, such as tallow or animal fat.

This ingredient is organic, colorless, odorless, and non-toxic.

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

Learn more about Glycerin

Glycol Distearate

Emollient, Emulsifying, Skin Conditioning

Glycol Distearate serves as a pearlizing or opacifying agent in cosmetic products.

It's often included in cleansers and haircare products to give them a lustrous or shimmering appearance.

It is derived from stearic acid, a natural fatty acid commonly found in vegetable oils and animal fats.

Glycol Distearate isn't fungal acne safe.

Learn more about Glycol Distearate

Hydrolyzed Hyaluronic Acid

Humectant, Skin Conditioning

Hydrolyzed Hyaluronic Acid is a form of hyaluronic acid. It is created by the hydrolysis of hyaluronic acid with a high molecular weight. Once created, Hydrolyzed Hyaluronic Acid has a low molecular weight.

Low molecular weight HA has been shown to hydrate and increase elasticity of the skin. Increasing elasticity is also associated with reduction of wrinkle depth.

One study found topical low molecular weight hyaluronic acid may be considered for the treatment of rosacea in the adult population. However, we always recommend speaking with a professional about your skin concerns.

Hyaluronic acids are a humectant. This means they draw moisture from the air. Hyaluronic acids help moisturize, soothe, and protect the skin.

Read more about other common forms of hyaluronic acid:

Learn more about Hydrolyzed Hyaluronic Acid

Panthenol

Skin Conditioning

Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.

There are two forms of panthenol: D and L.

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.

Learn more about Panthenol

Sodium Chloride

Masking

Chances are, you eat sodium chloride every day. Sodium Chloride is also known as table salt.

This ingredient has many purposes in skincare: thickener, emulsifier, and exfoliator.

You'll most likely find this ingredient in cleansers where it is used to create a gel-like texture. As an emulsifier, it also prevents ingredients from separating.

There is much debate on whether this ingredient is comedogenic. The short answer - comedogenic ratings don't tell the whole story. Learn more about comegodenic ratings here.

The concensus about this ingredient causing acne seems to be divided. Research is needed to understand if this ingredient does cause acne.

Scrubs may use salt as the primary exfoliating ingredient.

Learn more about Sodium Chloride

Sodium Cocoyl Isethionate

Cleansing

Sodium cocoyl isethionate is a natural ingredient from coconut oil. It is an ultra gentle cleanser that gives a nice foam without drying the skin or impacting the skin barrier.

The amount of foam created depends on the amount of sodium cocoyl isethionate used in the product.

This ingredient also helps improve the spreadability of a product.

Learn more about Sodium Cocoyl Isethionate

Sodium Methyl Cocoyl Taurate

Cleansing, Foaming

This gentle cleansing and foaming ingredient is known for leaving a smooth feeling in skin and hair. It is made using coconut oil.

According to the manufacturer, it is soluble in water and has resistance to hard water, acid, and alkali.

Due to its coconut base, it may not be Malassezia folliculitis safe.

Learn more about Sodium Methyl Cocoyl Taurate

Water

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. Stay hydrated!

Learn more about Water