Since they both can be dark beverages and contain tannic acids, coffee and tea are big offenders when it comes to staining your teeth. The problem here is that tooth enamel, or a tooth's outer layer, is really porous. Beverages can therefore seep into those pores and stay there. Tooth enamel, by the way, isn't the white part of your tooth; it's actually a semi-translucent covering of the dentin, the white layer underneath. Coffee is full of chromogens, causing stains on your enamel that make your teeth look discolored over time.
Tea, usually seen as a healthy beverage, is just as bad as coffee -- if not worse -- when it comes to staining teeth, because it's full of tannins. Tannin-rich black tea causes the most problems for your teeth; herbal, green and white teas are not as likely to stain them.
Much like tea, some foods that you consider healthy may not be so great for the appearance of your teeth. What are the worst offenders? Read on to find out.