There are two primary causes for people s teeth becoming more yellow or brownish with aging. The most common cause is the superficial stains that originate from certain foods and drinks and stain the external surface of the teeth. This can happen with intensely colored foods or beverages such as red wine, tea, coffee, or tobacco. As the person continues to consume such foods or substances over a prolonged period of time, the stains become more stubborn.

The second reason for the teeth to lose their natural white color with age has to do with the intrinsic nature of teeth. The natural tooth color basically comes from an inner layer of the tooth, known as the dentin layer. This layer is covered with an opaque material called enamel. As the person ages, with more wear and tear, the enamel becomes progressively thinner. This results in the opaqueness of the teeth to be compromised resulting in the visibility of the more color intense dentin layer. In effect, it causes the teeth to appear yellower or darker than original.

Apart from strongly colored foods causing stains, there are other external factors that affect the natural color of teeth. Some people have silver based fillings for their dental cavities. Over a period of time, these silver fillings tend to make the tooth appear dark or gray in color. Certain types of medications are also known to cause discoloration of teeth.

If the person has not maintained good oral hygiene and regular dental visits over the years, dental plaque and tartar can accumulate. This can have an adverse effect not only on the health of the teeth, but also may spoil the natural bright color of teeth after some time.

Therefore, maintaining good dietary habits and good oral hygiene practices are recommended to retain the natural color of teeth as a person ages. .