Mac Cosmetics Pro Longwear Nourishing Waterproof Foundation - NC40 Versus Estée Lauder Double Wear Stay-in-Place Foundation - 3C1 Dusk

Laureth-7 is created by the ethoxylation of lauryl alcohol using ethylene oxide. Lauryl alcohol is a fatty alcohol with hydrating properties.

This ingredient is an emulsifier and cleansing ingredient. As an emulsifier, it is used to prevent ingredients from separating. It also helps cleanse the skin by gathering dirt, oil, and pollutants to be rinsed away.

Methicone is a type of silicone and is a simpler form of dimethicone.

Silicones are used to enhance the texture of products and have emollient properties. Methicone is used to give products a silky texture and improves spreadability.

Mica refers to a group of silicate minerals. Mica crystals are easily split to give products a shimmer. These crystals are able to reflect light to temporarily give your skin a glowy look.

Mica is found to be safe. Trace amounts of heavy metals may be found in mica, but these metals are not harmful in our personal products.

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.

This ingredient is a preservative with antimicrobial properties. It is the sodium salt of dehydroacetic acid.

It is especially effective at preventing bacterial and fungal growth in low concentrations.

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.

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.

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.