There are many tooth whiteners which promise incredible results, but they rarely work and can be pretty expensive.
Luckily, as with many other problems, there is a natural tooth whitener which is made from fermented apples and works wonders for your yellow teeth. The remedy contains essential enzymes, minerals and vitamins and can remove the stains from your teeth and the bacteria in your mouth.
What makes apple cider vinegar good for tooth whitening?
ACV is a powerful disinfectant with a mild action which removes stains, whitens your teeth and kills all bacteria in your oral cavity.Dilute some ACV with water and gargle the solution in the morning to whiten your teeth and prevent other problems.
When using ACV on your teeth, shake the bottle first as the compounds are often at the bottom of the bottle. Always dilute it with water as pure ACV is acidic and may strip the enamel off your teeth, and avoid using it more than once a day.
Source : http://www.justnaturallife.com