Another day, another TikTok trend – only this time, the latest fad has actually been around for decades. Joining the ranks of other blast-from-the-past crazes such as low-rise jeans, pucca shell necklaces, and butterfly clips, mewing – the practice of changing your tongue position to strengthen and define your jawline – is the latest example of “what’s old is new again.” Unlike the other trends topping social media charts, however, mewing is not necessarily as harmless as donning a claw clip or attempting to pull off brown lipstick. Ahead, experts break down everything you need to know about mewing and whether it’s all Gen Zers claim it’s cracked it up to be.
What Is Mewing?
The practice of mewing is named after its reported founder, John Mew, a 93-year-old former orthodontist from the UK. “He believes children can achieve straighter teeth and better breathing habits using techniques like mewing, arguably instead of traditional treatments like orthodontics or surgery,” says Los Angeles-based dentist, Rhonda Kalasho, DDS.
For years, Mew practised what he coined as “orthotropics,” focusing on altering the jawline and face shape of his patients through facial and oral posture and exercises. But, in 2017, he was stripped of his dental license by the General Dental Council in the UK “on grounds of misconduct for publicly denigrating the traditional practices of orthodontic tooth movement,” according to an article in the Journal of Oral and Maxillofacial Surgery.
At its most basic, mewing is a technique that involves changing your tongue’s placement to improve breathing and, according to the many mew-ers on the internet, create a more defined-looking jawline. Mewing is all about “retraining the resting tongue position” or tongue posture, according to the same journal article. “When resting, patients are instructed to seal their lips and press their tongue against the posterior hard palate [roof of the mouth] as opposed to on the floor of the mouth.” Maintaining proper – vs. slumped – posture is also key.
If it feels weird, that’s likely because your tongue might normally rest at the bottom of your mouth (although experts say that’s not really a “healthy” position) vs. against the roof of it. The more you practise mewing, the more you can become accustomed to this new tongue placement so that it ultimately becomes your tongue’s instinctual resting position, according to the article. The goal is “to increase the cross-sectional area, which provides 1) space for the teeth to align naturally, 2) a huge increase in tongue space,” which is supposed to improve swallowing, breathing, and facial structure, according to the London School of Facial Orthotropics, (FWIW, the school was founded by Mew), despite his work being “mostly discredited” and considered by orthodontic researchers as straight-up “wrong,” according to The New York Times Magazine. Needless to say, whether or not mewing actually yields those results, however, is iffy at best.

But over on TikTok, where #mewing has 205.5 million views, fans of the technique seem fairly confident that this tongue exercise does leave them with sculpted jawlines. Take, for example, TikTok user @sammygorms, who “literally thought the only option left [to give her jawline shape] was fillers” until she tried mewing and it “changed her face,” she claims.
And then there’s @killuaider, who first posted a video in December showing off her mewing before and after photos with the text “tongue posture is such a powerful tool.” Two months later, the TikTok user shared another clip only this time she couldn’t stop smiling, explaining in the caption, “I JUST FELL IN LOVE W MY OWN SIDE PROFILE.”
Need not forget that you can’t trust everything on the internet…
But Does Mewing Actually Work?
It’s important to note that mewing as it’s being shown on TikTok isn’t exactly what Mew intended. The mew-ers on TikTok and YouTube seem less concerned with straighter teeth and better breathing and more focused on achieving a certain aesthetic – even just for a 60-second video. “I would think there is only a very small population that’s interested in long-term orthodontic movement through the act of mewing,” says California-based dentist, Ryan Higgins, DDS. “Most young people are just trying to make their selfies look better.”
It’s almost as if modern-day mewing is, in Higgins’ words, “something you can do to take a better picture without the help of social media filters from sites such as Instagram, Snapchat, and TikTok.” But like a filter, the jaw-slimming effects of mewing are fleeting. “Sure, manipulating your facial muscles to change the shape of your appearance can work for a very temporary amount of time,” he says. “Bodybuilders do it every time they flex on stage. However, as soon as you relax your taut muscles, your soft tissue will return to its resting position and thus makes mewing very temporary as a means to reshape the jawline and eliminate a ‘double chin.’”
Even if you practising mewing regularly, any jaw-sculpting results will likely still be ephemeral. What can last, however, are the lingering side effects of mewing. “The technique is based on the strengthening of certain facial muscles,” explains Kalasho. “Therefore, if you stop mewing, the effects could dissipate. However, mewing is not without its risks, either as it requires you to keep your teeth touching throughout the day, potentially causing a lot of “teeth wear” and cracks in the enamel, adds Kalasho. What’s more, if done incorrectly, mewing “can cause pain in the back of the neck, in the mouth, and you can perhaps cause misalignment of your teeth.”
But what about all the so-called proof of more defined jawlines on TikTok? Experts concede that repositioning your tongue might very well define your jaw for the moment, but overall, there’s “no scientific evidence to back this practice,” according to Jeffrey Sulitzer, DMD, chief clinical officer at SmileDirectClub.
If you’re looking for straighter teeth or sounder sleep (thanks to better breathing), best not to take matters into your own hands and instead consult an actual medical professional. A dentist or orthodontist can help determine the best course of action for conquering crooked teeth, misalignment, or other mouth woes.

And even if you are just hoping for a slightly more sculpted jawline, Sulitzer emphasises the importance of seeking out expert advice vs. DIY. “I would not recommend this practice [of mewing] to my patients, and especially not without the guidance of a dentist or an orthodontist,” he says. Other pros echo that sentiment. “Mewing is fine for a picture here and there, but if you’re trying to change the shape of your face, you want to make sure you’re doing it correctly,” says Zainab Mackie, DDS, aka @drzmackie “Your TikTok Dentist” on the platform. “Self-diagnosis is always dangerous. This is why it’s best to consult a physician or dentist and make sure you receive guidance from them.”
As with the many other dental-related fads that came before (i.e. using magic erasers on teeth or oil pulling) you can likely expect this one to die out as quickly as it rose to a viral level. Yes, mewing has the potential to sharpen the jawline and “eliminate the ‘double chin’ for your perfect selfie,” says Higgins. But once the flash goes off, let your mouth and muscles relax. And if you still have any cosmetic or medical concerns, use your tongue for talking…to a dental professional, who can give legit, evidence-backed advice.
This story first appeared on www.shape.com
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