Discoloration of your teeth can be caused by food and drink. One other possibility is you may have gum issues. Sometimes when your gums are infected, the gum tissue can appear off color. Since you have a lot of gum tissue surrounding your teeth, even a slight change in gum color can make your teeth appear they are yellowing. Visit your dentist. Get your mouth checked. If there are gum issues. Please have it taken care of. Start on a good home care routine. Ask how you should be flossing. Working in dental offices, I cringe when I hear the person cleaning a patient's teeth say, "You know how to floss." Ask how you should be brushing. My experience when I clean patients' teeth is, the patient is in the chair, but the patient's mind is somewhere else. I don't know if it is boring or embarrassing. If the patient was bored, the patient would be doing home care. If the patient has made up his or her mind that I will do what I want, then that is an attitude problem. Attitude is the hardest thing to change. GETTING your teeth whitened will be done after your gums have been checked for gum disease or inflammation. Whitening your teeth when your gums are not healthy can cause gum inflammation. That is why you are advised to have your teeth checked before whitening is done. I have added more information because there are several reasons why your teeth may appear off color. I am OFFERING information to them.