whitening teeth?

is there a way where i don't have to fork out for expensive treatments or messy kits to get naturally whiter teeth? like avoiding certin food ect.. give us any helpful hints thank you x x x
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for years people have used BAKING SODA to whiten their teeth. Wet your toothbrush and dip into the soda. The longer you brush your teeth and more often, they will become more whiter. Cocoa
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