No one can live without water, and it would seem many can't survive without tea, either. It's the second most consumed beverage behind plain old H₂O. Ancient cultures have been imbibing the stuff for thousands of years, but its good-for-you qualities—particularly those derived from green tea—have only reached the consciousness of the mainstream during the last decade or two. Though only a relatively recent obsession on these shores, the ever-growing body of evidence linking green tea to a host of health benefits has led many to claim it to be the elixir of life.

Most of green tea's medicinal properties can be attributed to the plant's antioxidant powers. All of the four main tea varieties— black, green, oolong, and white—are loaded with phytochemicals called polyphenols. Green tea, though, has the highest content of a special type of polyphenol known as catechins. You may have heard of EGCG, the potent catechin found in green tea. It's nearly 20 times more powerful than vitamin C and can gobble up free radicals that harm the body's cells. While many of the studies looking into the benefits of green tea for the skin have been done on cell cultures or animal models, there is still plenty of evidence indicating the plant's potent skincare powers.

For example, animal studies have shown green tea may be able to prevent certain types of UVB-induced skin cancer. It may also boost skin's natural protection against UVB, which is why some skincare experts suggest using products that contain green tea extract in conjunction with a daily SPF moisturizer. There have also been studies that suggest the ingredient may help suppress collagen degradation and boost skin's elastin content, both of which can help reduce wrinkles. "A spa client who wants to incorporate a more aggressive treatment against premature aging and sun damage into their regimen would be wise to choose green tea treatments," says Barbara Close, founder of Naturopathica. At the brand's East Hampton spa, such clients can add the Green Tea Wasabi Antioxidant Treatment ($25) to the Pure Results Facial ($120, 60 minutes). Wasabi is a stimulating ingredient that gives skin an instant glow (the spa has even marketed the package as a "Saturday Night Special" for guests getting ready for a special occasion), while over time the polyphenols in the green tea go to work rebuilding the cells below the surface. At The Spa at the Mandarin Oriental, Miami, the Advanced Lifting Facial ($210, 80 minutes) is perfect for mature skin or anyone with a dehydrated or sun-damaged complexion.

Green with Envy

Not only do the polyphenols in green tea give the plant antioxidant powers, but they also provide anti-inflammatory properties. One study found that green tea polyphenols can help reduce inflammatory lesions in people with rosacea, making the ingredient perfect for treatments suited to sufferers. Green tea extract can also be a boon for the complexion post peels or microdermabrasion sessions. The Spa at Four Seasons Hotel Las Vegas offers the Green Tea Pomegranate Peel ($165, 50 minutes). This highly enzymatic facial incorporates 20 percent lactic acid to slough off dead cells and green tea to help calm and soothe skin. The anti-inflammatory benefits of green tea, along with its antibacterial properties, are also known to help treat acne. A study even found a 3 percent green tea cream to be as effective on moderate to severe acne as a 4 percent benzoyl-peroxide cream, and with fewer negative side effects.