$7 Charcoal Toothpaste Whitened My Teeth Immediately. Here's Why I'm Leaving it Behind

After a quarter century of downing black coffee (I snuck my first cup at the tender age of five), and many years of allegiance to red wine as my adult beverage of choice, my teeth, like all those subjected to a near-daily deluge of dark drinks, weren't as bright as I knew they could be.

And because the battery of whitening products that I'd been using couldn't keep pace with my consumption, I kept my eyes peeled for an alternative that would. One morning, while I was brushing my teeth with a mass market product, I saw a Facebook post from a college friend about a charcoal toothpaste that had dramatically improved his smile. His post promised a slightly funky taste and the kind of stain-fighting properties that, frankly, sounded too good to be true. But it was on Amazon Prime, (then as now, it was on sale for $7 instead of the customary $9), and I figured I could skip a cold brew iced coffee that day and put the money toward the hope of a brighter smile.

After about three weeks of brushing dutifully with Twin Lotus Activated Charcoal Toothpaste, which sort of tastes like someone liquefied a clove cigarette, my teeth were noticeably whiter. I recall being surprised that they got whiter even though I didn't ease up on coffee, wine, or tea after I started using it. I was so impressed that I started telling friends. I even made it the subject of an Instagram story that inspired people to slide right into my DMs with lots of questions: Was the taste that bad? (You get used to it!) How long did it take to see results? (Honestly, I noticed an improvement after about two days.) Was it worth the money? (Whiter teeth in two days? Absolutely!) At last count, no fewer than 17 friends had made the switch.

But here's the thing: This toothpaste, and much of the larger ecosystem of charcoal toothpastes, which tout the main ingredient's stain-absorbing power as the key to whiter teeth, don't include fluoride, the one thing that many dentists say is necessary. Dr. David Okano, an assistant professor at the University of Utah, explained in a 2016 interview that "fluoride will help reduce the demineralization process, which is the first stage to tooth decay. Also, if you have the demineralization but not yet a full blown cavity in the tooth, the fluoride can be taken up into that demineralized area to help it remineralize." He added that fluoride also enhances the effect regular brushing has on dental plaque buildup, another key factor in tooth decay and gum disease.

Luckily, at least one company has rolled out a toothpaste that blends both charcoal and fluoride, combining the stain absorbing power of one with the decay fighting power of the other. And when I'm done with my third consecutive tube of Twin Lotus, I'll likely switch to Curaprox's Black is White toothpaste. It's three times the cost of what I'm using now, but having my original teeth still in my skull in another quarter century is worth the price.