A recent Chicago College of Dentistry study showed that people who rinsed their mouths with black tea multiple times a day had less plaque buildup than those who rinsed with water.

"Polyphenols in tea suppress the bacterial enzyme that triggers plaque accumulation," says Christine D. Wu, Ph.D., the lead study author. "Drinking tea a few times a day could have the same effect."

Gourmet coffee houses have introduced a whipped frozen green tea drink which includes sugar and fat content that increases the buildup of bacteria in the mouth due to the heavy sugar content in the whipped cream-covered, fat-filled, sweetened drink. Those drinks also are made with green tea extract, rather than traditional fermented black tea which offers the cleansing effect mentioned in the dental study.