Can Charcoal Toothpaste Really Whiten Teeth?

People have known for a long time that charcoal can help purify water. Charcoal is largely carbon, which is why it’s black, and carbon is a friendly atom that likes to attach to other organic molecules. By passing water or air through an activated charcoal filter, you can remove a lot of impurities like pollens, bacteria, and bad smells. It won’t get rid of everything, but it can get rid of a lot.

However, just because activated charcoal is good at cleaning one thing doesn’t make it good at cleaning everything. Most kinds of charcoal are harmless enough to swallow, and its ability to absorb other molecules means you can use it for certain kinds of poisoning. But that doesn’t make it a good ingredient for toothpaste.

Charcoal in toothpaste isn’t really a new idea. Charcoal has been used to clean teeth in many times and places, but there’s a reason it got left out of toothpaste in recent decades, at least until the current fad.

Most toothpaste include an ingredient called an abrasive. The abrasive is a gritty substance that scrapes and polishes your teeth, but it’s just the right size and hardness to leave your enamel alone. This fact is important because your enamel never grows back. Fluoride works by recrystallizing enamel that bacteria have dissolved, but it can only reverse some of the damage.

The reason charcoal can appear to whiten teeth has nothing to do with the way activated carbon traps certain molecules. Charcoal is actually an abrasive, and it’s an abrasive with big enough and hard enough particles that it scrapes away enamel and not just the plaque on top.

If your teeth become whiter, it’s because the charcoal has removed the outer layer of enamel and all the stains on it to reveal a fresher layer of enamel underneath. But doing that weakens your teeth, opens you up to more cavities, and eventually works in reverse because it brings the yellow dentin layer closer to the surface.

So while activated charcoal has plenty of valuable uses when it comes to cleaning water, air, and even sometimes your body, it is not a good ingredient for cleaning your teeth. The best path to white teeth is the same as it’s always been: good oral care, peroxide strips, and professional whitening sessions with a trained dentist.