Methylparabens are a type of chemical that manufacturers often use as a preservative. People can add them to food, cosmetics, and pharmaceuticals to increase shelf life and avoid bacterial and fungal growth. Methylparabens belong to a group of chemicals known as parabens.Methylparaben is one of the most common parabens. You can find it as part of a paraben mix in most cosmetic products, where it prevents germ growth. It can also be found naturally in some fruits and may be used as a food preservative or an antifungal preservative.