Poor diet and hygiene can leave the outer, visible layer of the tooth, known as enamel, yellow, brownish, or off-white. Anyway you color the situation, it's not a pretty look.
For those with stain-prone teeth, it may seem obvious to steer clear of coffee, tea, soda, wine, and tobacco, but did you know that even produce can tarnish your smile? Blueberries, for example, can tint your teeth as surely as a glass of Merlot.
There are other factors that darken teeth from the inside out, including hereditary diseases, high fluoride levels, and medications like antihistamines, blood pressure prescriptions, and antipsychotic drugs.