Watch What You Eat
Dark foods and drinks, such as berries, red wine and coffee are the most common culprits to staining your teeth, as are foods with vibrant colors such as curry. Passing on these items when you're trying to whiten your teeth can only help, but if they can't be avoided, you should rinse your mouth with water after eating to minimize the amount of contact your food has with your enamel.
Other foods can be helpful when it comes to cheap teeth whitening. Crunchy vegetables and fruits, such as apples and celery, won't bleach your teeth but they can help scrub away surface stains, leaving a brighter smile. Nuts and similarly crunchy foods also produce a considerable amount of saliva as you chew them, according to the American Dental Association (ADA), allowing you to rinse lingering debris off of your teeth naturally. The fibrous quality of the vegetables and fruits helps to scrub your teeth clean and white, too.
Eating cheese can also help whiten your teeth. The calcium and lactic acid found in cheese and other dairy products can help strengthen your enamel, making your teeth look whiter. As a bonus, harder cheeses, such as Parmesan, can also help scrub your teeth, removing surface stains.