Pentylene glycol is typically used within a product to thicken it. It also adds a smooth, soft, and moisturizing feel to the product. It is naturally found in plants such as sugar beets.

The hydrophilic trait of Pentylene Glycol makes it a humectant. As a humectant, Pentylene Glycol helps draw moisture from the air to your skin. This can help keep your skin hydrated.

Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.

It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.

Tocopheryl Acetate is AKA Vitamin E. It is an antioxidant and protects your skin from free radicals. Free radicals damage the skin by breaking down collagen.

One study found using Tocopheryl Acetate with Vitamin C decreased the number of sunburned cells.

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.

Trisodium Ethylenediamine Disuccinate is used to help stabilize a product.

It is a chelating agent, meaning it helps prevent metal ions from binding to other ingredients. This prevents unwanted reactions in products. Metal ions can come into a product via the water ingredient. They are found in trace amounts and are not known to be harmful.

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.