Green tea can stain the teeth, though not as much as black tea because of its lighter color. Tannins in tea promote staining of the teeth by causing chromagens, the pigmented molecules in foods and beverages, to attach to the dental enamel.
Staining of the teeth can be minimized without the need to entirely avoid tea and other stain-promoting beverages. Simply minimize the contact between the teeth and the beverage by using a straw and swallowing promptly. It helps to swish with water, too, immediately after drinking. Chewing sugarless gum is another means of removing the stain-promoting substances left in the mouth after eating or drinking.