COSRX The Niacinamide 15 Serum Ingredients Explained

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

• It is a solvent, meaning that it helps to dissolve other ingredients. This also enhances the absorption of the product into one's skin.
• It is a humectant, which means that it helps attract moisture into the skin.
• It helps improve product application.

Overall, Butylene Glycol is a safe and well-rounded ingredient. It is unlikely to irritate skin, and works well with pretty much all other ingredients.

Acetyl Glucosamine is an antioxidant and humectant. It is a form of Vitamin C.

Acetyl Glucosamine helps the skin produce hyaluronic acid and boost hydration.

1,2-Hexanediol is a multi-tasker ingredient. It acts as a preservative to increase shelf-life and can aid other preservatives in preventing microbe growth. 1,2-Hexanediol also helps the skin retain moisture as a humectant.

In products that are water-based, this ingredient can help stabilize perfumes and fragrances. It can also help make the texture of products softer and more smooth.

Zinc PCA (or "zinc salt") differs slightly from zinc itself. PCA stands for pyrrolidone carboxylic acid. However, Zinc PCA comes from zinc.

It can help reduce redness, regulate sebum, and promote the general healing process of the skin.

Trehalose is a disaccharide made of two glucose molecules (glucose is sugar!). Trehalose is used to help moisturize skin. It also has antioxidant properties.

As a humectant, trehalose helps draw moisture from the air to your skin. This helps keep your skin hydrated.

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

We don't have a description for Pullulan.

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.

Ethylhexylglycerin (we can't pronounce this either) is commonly used as a preservative and skin softener. It is derived from glyceryl.

You might see Ethylhexylglycerin often paired with other preservatives such as phenoxyethanol. Ethylhexylglycerin has been found to increase the effectiveness of these other preservatives.

Sodium Phytate is the synthetic salt form of phytic acid. Phytic acid is an antioxidant and can be found in plant seeds.

Sodium Phytate is a chelating agent. Chelating agents help prevent metals from binding to water. This helps stabilize the ingredients and the product.

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

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.

Tocopherol (also known as Vitamin E) is a common antioxidant used to help protect the skin from free-radicals and strengthen the skin barrier. It's also fat soluble - this means our skin is great at absorbing it.

Vitamin E also helps keep your natural skin lipids healthy. Your lipid skin barrier naturally consists of lipids, ceramides, and fatty acids. Vitamin E offers extra protection for your skin’s lipid barrier, keeping your skin healthy and nourished.