TikTok told me cavities are contagious and now I’m scared to kiss people

Do I need to worry? A dentist weighs in.

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Dr. TikTok

By basically anyone’s standards, I’m kind of a health nut. A large part of my job is knowing about evidence-based health practices, after all. So when I saw this TikTok warning people that cavities are contagious, I was floored. Not only have I been blissfully unaware that tooth decay is infectious, it certainly never occurred to me that I could “catch” a cavity with a simple kiss. Now this viral TikTok has me scared of kissing people.

The TikTok in question was posted in March by Tasneem Mahmood, a Houston-based dentist. In it, Mahmood’s hands literally shake the drink out of her hand when she thinks about kissing her husband, who has cavities. The video has a kind of cheerful scary vibe that really speaks to my anxious nature.

As I watched it this morning, I thought about the dozens of people I exchanged casual kisses with yesterday at the Gay Easter Parade and wondered: “Do those little pecks count? It wasn’t even like that. We were just being gay.” Yes, I know it’s possible to catch COVID with a simple saliva swap, but tooth decay? C’mon.

Other people who follow Mahmood had similarly freaked out responses. "New fear unlocked," one person commented. Others were indignant. “I really don’t Belive it even tho Ik it’s true my bf has major teeth cavities that have been years on years trying to fix and I’ve never had a Cavity,” wrote another commenter. Another simply asked, “Cavities are contagious?”

For her part, Mahmood has been unbelievably diligent about responding to all the confusion and terror her follwers expressed in their comments. “Let's not forget that cavities are often the result of not brushing and flossing daily, though research suggests some people may be genetically predisposed to getting them, regardless of immaculate dental hygiene,” Mahmood told Insider. She also cleared up some of the confusion about kissing. “I’m not trying to get in the way of your smooches! Just make sure you floss, brush and rinse w mouthwash after,” she posted.

In case you’re wondering: Yes, you can “catch cavities.” “Cavities are contagious if you have the bacteria that causes them and you kiss somebody,” Nammy Patel, a dentist in San Francisco, tells Mic. Oh great.

Patel also adds that some gum diseases can be transmitted from person-to-person, namely the very familiar gingivitis. This is consistent with recent research into oral health. A 2014 study suggested that parents transmit the bacteria that causes cavities to babies when they clean pacifiers by putting them in their own mouths and then back in the kid’s.

The thing is that, unlike infants, we are responsible for our own dental hygiene and we can prevent a lot of bacteria from becoming a problem — tooth decay or a cavity — by simply doing the basics: flossing and brushing regularly. Patel also recommends asking your partner to do the same.

Patel adds that romantic partners can really keep each other healthy. Patel explains that she sees clients who only come in because of their bad breath and, while “eww” is not what you want to hear from someone you’re swapping spit with, it can help you stay orally healthy. “Bad breath is absolutely a sign that something is up and they need to have a professional take a closer look at what's going on in their mouths and to treat the cause rather than the symptoms,” Patel says.

Mahmood said in her comments that she was not trying to dissuade people from kissing at all, she just wanted to remind everyone that our hygiene affects us and everyone we come into kissing close contact with. "The takeaway message from all of this is: practice good oral hygiene, and you'll have great control and be on the safe track," Mahmood told Insider. Okay, look, maybe I didn’t want to think about that dentist appointment I’ve been procrastinating today, but this TikTok-induced anxiety may serve a purpose. As Patel says, “People should always be concerned about oral health.”