Q & A Library

White tea, imported mostly from the Fujian Province of China, is the least processed form of tea -  to make it, leaves are simply picked and air-dried. Perhaps for that reason, white tea does have even greater antioxidant activity than green tea, which is produced by picking, heating (steaming or pan firing), and drying the leaves. To make black tea, another step, oxidation, is required. White tea comes from the same plant as black and green tea, Camellia sinensis, and has a delicate taste and pale color. It releases the least amount of caffeine of all three teas, typically from five to 15 milligrams per cup.

I haven't seen any evidence that white tea protects oral health any better than other types of tea, but studies at the University of Illinois College of Dentistry have shown that compounds in black tea can destroy or suppress growth and acid production of cavity-causing bacteria in dental plaque. Black tea also affects an enzyme responsible for converting sugars into the sticky material that plaque uses to adhere to teeth. Furthermore, upon exposure to black tea, the Illinois researchers learned that certain plaque bacteria lose their ability to adhere to others, thereby reducing the total amount of dental plaque that forms on teeth. They also found that rinsing with black tea for 30 seconds, five times in a row (in three-minute intervals), stops plaque bacteria from growing and producing the acid that breaks down teeth and causes cavities, although it might stain your teeth if you do this frequently (white tea is much less likely to cause this problem.) In addition, tea contains fluoride, which may further explain why it helps protect teeth.

Even if white tea works better than black tea to promote oral health, it would be a pretty costly mouthwash. Although widely available in the United States now, it can be more expensive than other types of tea. You can order white tea online from many sources, including one of my favorites, In Pursuit of Tea (www.inpursuitoftea.com).

Andrew Weil, M.D.