A tooth color depends on the composition and structure, the thickness of each tissue in which it is established. Yellowing of teeth can be substances that stain the enamel and plaque buildup. One of the most effective natural remedies for teeth whitening is baking soda. This solution is very cheap and thee of abrasive substances often used to whiten teeth that may affect enamel strong enough. Baking soda removes stains and imperfections of tooth enamel making teeth brighter.