By Erin Lukas
May 05, 2017 @ 6:00 pm

If you are the proud owner of a medicine cabinet stocked with serums but have no idea on what the skincare product actually does or how you’re supposed to use it, you’re not alone. Like a non-absorbent makeup sponge, serums are full of contradictions: they’re moisturizing, but shouldn’t replace your moisturizer, and some formulas are oily, but they’re not classified as face oils.

Confused? Us too. We turned to dermatologist Dr. S. Manjula Jegasothy, MD, CEO, and founder of Miami Skin Institute to break down what serums are, how the product should be used, and what formulas are best for your skin type.

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So, What Is a Serum?

 Serums are like a shot for the skin. They’re packed with potent anti-aging ingredients like retinol and vitamin C, and blended with non-oil based agents, which is what makes formulas moisturizing. “Facial serums employ synthetic substances such as silicone and glycerin to produce the thin texture and slippery feel of a serum without utilizing pore-clogging, heavy, ingredients such as shea butter or jojoba oil,” says Dr. Jegasothy.

How Do You Use Serums In Your Skincare Routine?

Treat serums as the grand finale in your skincare routine. Dr. Jegasothy says to apply them after the rest of your products, right before you start on your makeup. “If you are applying other skincare products over serums, your face may start to appear too shiny, particularly as the day goes on,” she says.

To apply serums, Dr. Jegasothy recommends using clean finger tips as you would with other products, and adopting light upward strokes. As with eye creams, she says to pay careful attention when using serums around the eye area. "Applying anything to the eye area should be done very gently, in a patting method," explains Dr. Jegasothy. "Do not ever rub creams or serums into the eye area as it can break delicate capillaries situated under the thin eyelid skin, which can then cause under eye circles later."

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How Do I Pick the Right Serum?

When serum shopping Dr. Jegasothy recommends considering brands that have good reputations, clinically test their products, and divulge their ingredient list. If they have high ingredient concentrations, the better. 

In terms of actual ingredients, if you have oily skin she suggests choosing a serum with salicylic acid and/or glycolic acid. For dry complexions, look for formulas that incorporate hydrating proteins such as hyaluronic acid that attract water to the skin. While aging, dull, or combination skin will benefit from serums with both vitamin C and retinoids.