Cetaphil Gentle Skin Cleanser - US Versus LUSH 9 to 5 Cleansing Lotion

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.

Methylparaben is a preservative and is a paraben. It is used to prevent the growth of fungus, mold, and other harmful bacteria. Parabens are chemicals used as preservatives in both cosmetics and food.

Methylparaben can be synthetically created. It can also be found naturally in some fruits, such as blueberries.

Propylparaben is a preservative and is a paraben with antifungal and antimicrobial properties.

This ingredient can be naturally found in plants and insects, but most of it is synthetically manufactured for human use. In cosmetics, it is usually created by reacting para-aminobenzoic acid and propanol (an alcohol).