What Causes Yellow Teeth? Do you have yellow teeth? Are you looking for a smile makeover? It’s best to start by evaluating your whitening needs and goals by looking at the color of your teeth and your habits or other factors that may have caused discoloration: Diet : Certain foods that are high in tannins, such as red wine, are potential causes of yellow teeth. Some of the most common causes of tooth discoloration include drinking beverages such as coffee, soda, and wine. These substances get into the enamel of your teeth and can cause long-term discoloration. Smoking : Smoking is one of the top causes of yellow teeth, and stains from smoking can be stubborn. But smokers can improve their yellow teeth by quitting smoking, following a complete oral care routine of twice-daily toothbrushing and daily flossing, and using the right teeth-whitening products. Illness : Certain medical conditions or medications are also causes of yellow teeth. Patients who are undergoing chemothe...