Kiehl's Fast Release Wrinkle-Reducing 0.3% Retinol Night Serum Versus MCoBeauty. Miracle Anti-Aging Repair Serum

Carbomer is a high-molecular weight polymer of acrylic acid. It is used to form gels and thicken formulas.

Due to its large molecular size, carbomer has minimal skin penetration and is considered an inert ingredient.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.

Glycereth-26 is a synthetic ingredient and polyethylene glycol ether of Glycerin. Glycerin is already naturally found in your skin and helps keep your skin moisturized.

It is a humectant and helps add texture to products. It can make your product thicker.

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.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin. 

It’s often used to:

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin 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.