Banana Peel For Whitening Teeth?

I recently looked up tips for effective ways to whiten teeth and i came across one that said the inside of a banana peel works very well. Can someone tell me how often to do this and to do this before or after brushing.
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I would use baking soda and water paste instead becasue the granules of the baking soda create a scrub that is more efficient and beneficial. But if you must use a banana peel, just rub the peel in circular motions a couple times a week. I would definitely do it before brushing! Banana breath smells. but yeah. i would use baking soda
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