What are some natural ways to whiten your teeth?

Not like the toothpastes or gum or white strips or anything... like is there anything else? like baking soda? does that work?
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There are some suggested home remedies for teeth whitening, but do be careful since most of them damage the teeth. Whitening Teeth with Lemon Juice Whitening Teeth with Wood Ash Whitening Teeth with Strawberries Whitening Teeth with Baking Soda For details of the procedure you can refer the source link below.
Source