While there are many store-bought options for whitening teeth, some people prefer to use natural methods. One way to whiten teeth is to brush with baking soda. Baking soda is a natural abrasive that can help to remove surface stains.  If you’re looking for a quick fix, you can also try using hydrogen peroxide. Hydrogen peroxide is a bleaching agent that can help to lighten teeth. To use this method, mix hydrogen peroxide and water in equal parts and swish the mixture in your mouth for one minute. Spit it out, then brush your teeth as usual.