Gary Fortinsky is a dentist and homeopath. He has this advice about getting your teeth whiter naturally;

"Chewing on neem sticks has been a form of dental care in India and Africa for centuries. Neem disinfects and helps maintain healthy gums, thus creating a natural shine on the teeth. Chewing on licorice sticks cleans the mouth and teeth, making them shine. Honey used on teeth and gums will slowly bring shine and health to the teeth. Garlic is a smelly way of getting bright, shiny white teeth."