Tooth whiteners are generally expensive and full of harmful chemicals. A lesser known (and less expensive) tooth whitener is strawberries.
Simply rub your teeth with a strawberry! You can leave it on for a few minutes but be sure to brush your teeth afterward (the acid can damage tooth enamel).
If something more powerful is required, mix the strawberry with a little baking soda and apply gently with your toothbrush. Leave for a few minutes then rinse and brush well. This can be done safely once a fortnight.
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