What is it? Caffeine, also known as trimethylxanthine or methyltheobromine, is a central nervous system stimulant found in a variety of foods including cocoa beans, coffee, tea and soda. It is used to treat cardiac ailments and in addition to a stimulant, caffeine is also a diuretic. When ingested, caffeine can be addictive, leading some people to a dependency upon their 'morning cuppa'. When used in cosmetics, caffeine's diuretic effect is believed to help deflate puffiness, increases circulation and minimizes dark circles underneath the eyes.

You'll find it in: Caffeine is found in a remarkable number of skincare products including eye creams, firming serums, anti-oxidant preparations, cellulite treatments and creams, cleansers, toners and moisturizers. There are also skincare products available that make use of the unripe coffee cherry or fruit, called a coffeeberry, which is rich in potent anti-oxidants.

Our product picks: To brighten eyes the day after the night before, use Murad Moisture Silk Eye Gel, with Allantoin and caffeine to hydrate and rejuvenate the skin. Protect the rest of the face with the anti-oxidant serum Topix Replenix Cream CF (Caffeine Enhanced). Lightly pat a few drops of this serum over the entire face, being sure to include the neck. To stimulate circulation and get the entire body ready to face the day, use Juara Skincare Invigorating Coffee Scrub, enriched with crushed Indonesian coffee beans, rice bran and walnut shells. Troubled by cellulite? Smooth the appearance of dimples and orange-peel skin with Bliss Fat Girl Slim or Pevonia Body-Svelt Gel—Cellulite, all enriched with caffeine to reduce the visible marks of cellulite.

Who should avoid it: Skincare products containing caffeine should be avoided by anyone with a sensitivity or allergy to caffeine. Also, pregnant women should check with their doctor before using anything with caffeine to verify safety.

What you can expect: With consistent use, skincare products containing caffeine may help reduce puffiness and inflammation and smooth skin texture, as well as help minimize the appearance of dark, under eye circles.

See also:

CoffeeBerry®: A Wakeup for the Skin

Tea: A Brew of Skincare Benefits

Combating Puffiness and Under-Eye Circles