Technically patients can eat immediately after having their teeth whitened, but dentists recommend that individuals wait 24-72 hours before resuming a fully normal diet. In the initial 24-72 hours patients can eat, though they should avoid foods (and beverages for that matter) that may cause re-staining or irritation of teeth. These foods may be very hard in texture, too hot, too cold, or dark in color (such as beets, red wine, and dark chocolate).