How To White Teeth In Minutes!! by How To White Teeth In Minutes!!Buy activated charcoal (should be at local drug store or online) break open the capsule and put it on a toothbrush and brush for about 3 minutes.Then brush your teeth like normal to get the black off. My friend did this and it really worked!! It makes your teeth like 3 shades whiter!! The activated charcoal doesn't taste like anything and is safe to use. There is even drinks made with it! I really recommend trying this it really does work!