Is there a natural solution for me to whiten my teeth instead of having to use abrasive methods?

I want to know any natural methods that actually work instead of having to use methods such as bleaching etc.
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The Herbal Body Book (A Natural Approach To Healthier Hair, Skin, and Nail) by Stephanie Tourles says that.... "strawberries have a slightly bleaching effect and help to rid the teeth of tea, coffee, and cigarette stains. A strawberry is much safer to use than lemon juice, which is too acidic." Her recipe for Strawberry Brightener Mash 1 medium-sized ripe strawberry. Dip your brush into the liquid and brush normally. From the Answerer: I must warn you that the seeds get stuck in your toothbrush, so you may want to have a separate brush just for the strawberry treatment. You would want to do this after regular brushing with toothpaste, of course. You can use thawed out berries that have been frozen, but make sure they do not have sugar in them. This is a tasty way to treat your teeth! ***This book has great recipes for natural facial steams, scrubs, toners, moisturizers, cleansers, masks, shampoos, etc. I got mine from Amazon for less than $4!!!
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