If you regularly start your morning with caffeine, you might want to start slathering it on your face as well as sipping it.

With everyones favorite pick-me-up growing in popularity as a skin care ingredient, we checked in with medical experts to see what really works and what has not yet been scientifically proven.

How It Works

Caffeine is being increasingly used in cosmetics, thanks to potent antioxidant properties and protection of cells against UV radiation, dermatologist Loretta Ciraldo , founder of Dr. Loretta skin care , told HuffPost. That protection slows down photoaging, including improving wrinkles and age spots.

Its strategically placed in certain skin care products, from eye creams to cellulite creams, for what people view as a pick me up effect, said dermatologist A. Shadi Kourosh , assistant professor of dermatology at Harvard Medical School.

One of the reasons its so popular is that its so good at penetrating the skin, the experts said. Its able to get where it needs to go, said dermatologist Rebecca Marcus , the founder of Maei MD Skincare . By constricting blood vessels, caffeine helps boost microcirculation, and it can reduce puffiness.

Dark Circles And Wrinkles? Caffeine To The Rescue

One area where caffeine is likely to be most effective is in the under-eye area, Because the skin in the under-eye area is thin, ingredients are able to penetrate and have a stronger impact, dermatologist Marisa Garshick explained. Caffeine is whats known as a vasoconstrictor.

Since it constricts or shrinks blood vessels, it reduces blood flow, which decreases inflammation and redness and depuffs swollen areas of skin, Kourosh said. Its helpful for swollen puffy eyes or flushing or redness of the skin, due to allergies, rosacea or alcohol which we know in the business as the skin hangover. Caffeine-containing products can help, because caffeine does the opposite of alcohol. Whereas alcohol dilates blood vessels in the skin, causing or worsening redness and swelling, caffeine can help neutralize them.

However, how effective it can be depends on whats causing the issue in the first place. Dark under-eye circles can run in a persons family, for example, Kourosh said. Health factors can cause them, and certain skin types are prone to them. So if there is more going on than just puffiness that doesnt resolve with a chilled compresses or caffeine-based cream, its time to consult a dermatologist.