Activated charcoal’s natural adhesive qualities let it bind with surface-staining culprits like coffee, tea, wine, and plaque, and take them off your teeth for good when you spit it out, Banker says. However, its whitening power stops at stains—if your teeth are naturally darker or yellow, you’ll need to buy a product with a bleaching agent like hydrogen peroxide or try an in-office treatment. MORE: 7 Foods For A Brighter Smile As far as safety goes, the fine, odorless and tasteless powder is kosher to ingest—it’s sold in health food stores in tablet form. But Banker and ADA officials warn that until we know if it’s gritty enough to damage enamel, you need to avoid actually scrubbing it on your teeth. “Right now, no charcoal teeth whitening products have been evaluated and accepted by the ADA,” says Kimberly Harms, DDS, an ADA Consumer Advisor spokesperson. “Our biggest concern is abrasiveness—you don’t want it to wear away at the enamel.” Here’s how to give it a whirl—safely:1. Break2. Add3. Dab4. Wait 1–2 tablets of activated charcoal and pour the powder contents into a cup. just enough water to cover the bottom of the cup (a teaspoon should do the trick) and mix to form a paste. the paste on all exposed surfaces of your teeth. 3 minutes, and rinse. MORE: Snail, Kale, And Starfish: 3 Crazy Ingredients Now In Your Beauty Products