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.

Butylene Glycol

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

Disodium Cocoamphodiacetate

Cleansing, Skin Conditioning

Disodium Cocoamphodiacetate is a surfactant and helps cleanse skin. It is created from the fatty acids of coconut oil.

Surfactants help rinse oil, dirt, and other pollutants easily from skin. It has a faint fruit-like scent.

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

Glycine

Skin Conditioning, Buffering

This ingredient is an amino acid that helps build proteins and moisturizes skin. It is already present in our skin as our bodies produce them naturally.

Glycine already plays a role in helping keep our skin moisturized as amino acids transport moisture throughout our skin.

As collagen is made up of glycine and other amino acids, it is believed glycine may help our skin produce more collagen.

Learn more about Glycine

Histidine

Humectant, Skin Conditioning

Histidine is a semi-essential amino acid used by our bodies to create protein. It has humectant and skin conditioning properties.

Our bodies use histidine to create filaggrin - filaggrin is a structural protein that the skin uses in maintaining skin barrier.

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.

Learn more about Histidine

Isoleucine

Skin Conditioning

Isoleucine is an amino acid that helps reinforce our skin barrier. This amino acid plays a role in creating protein for the body.

Fun fact: Isoleucine is found in meat, fish, dairy, legumes, and nuts.

Leucine

Skin Conditioning

We don't have a description for Leucine yet.

Lysine

Skin Conditioning

Lysine is an essential amino acid. Your body is unable to produce it naturally and we mainly get lysine from food sources.

Our bodies use lysine for growth and tissue repair. The skin uses amino acids as a precursor for building protein, and therefore keratins, collagen and elastin.

Phenylalanine

Masking, Skin Conditioning

Phenylalanine is an amino acid. It is a skin soothing and hydrating ingredient. Amino acids play a crucial role in wound healing and skin hydration.

This ingredient is also used to help even out skin tone due to its ability to disrupt the melanin production process.

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.

Learn more about Phenylalanine

Proline

Skin Conditioning

Proline is an amino-acid. It helps moisturize the skin and plays an important role in creating proteins.

Our skin uses proline as one of the building blocks for producing collagen.

In medicine, proline is used as an osmoprotectant. This means it helps prevent oxidative degradation in other drugs.

Our bodies are able to produce proline naturally, but certain conditions may inhibit this production. In that case, proline can be obtained from eating egg whites, soy protein, dairy products, asparagus, mushrooms, and seaweed.

Learn more about Proline

Serine

Masking, Skin Conditioning

Serine is an amino acid naturally found in our body. Our bodies use amino acids to create protein.

Amino-acids help give keep our skin hydrated. They play an important role in the skin barrier, which keeps the skin plump and firm.

Serine is a non-essential amino acid, meaning we don't need to obtain it from eating foods.

Learn more about Serine

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

Threonine

Threonine is an amino-acid. It helps hydrate the skin and has antioxidant benefits.

Our skin uses threonine for creating collagen and elastin. Humans are not able to create threonine and must get it through eating foods such as fish, lentils, poultry, sesame seeds, and more.

Tyrosine

Masking, Skin Conditioning

Tyrosine is one of the amino acids used to create protein. It plays a role in melanin production.

A study from 2012 found tyrosine to show promising results in restoring skin volume.

Valine

Masking, Skin Conditioning

Valine is an essential amino acid. It is used by our bodies for tissue repair and muscle growth.

An essential amino acid is one in which our bodies cannot naturally produce so we must get them through diet. Foods such as eggs, dairy, red meat, and fish contain valine.

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

Learn more about Valine

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