Mewing is a technique in which the tongue is placed on the roof of the mouth in an effort to make the jaw bigger and more square. This may be done for aesthetic reasons and/or to correct orthodontic, breathing, and facial structural issues.
The “how to mew” technique has received a lot of attention on social media. However, oral and maxillofacial surgery experts warn there’s little evidence to support claims that it can actually change your jaw structure and appearance, or improve your health.
This article explains what mewing is and presents some of the research findings on jaw development and related health issues, like sleep apnea. It also discusses why it’s important to see a healthcare provider for facial structure concerns and avoid potential disinformation about mewing.
How to Mew
Rather than resting their tongues on the bottom of their mouths, as people naturally do, those who practice mewing rest their tongues on the roof of their mouths.2 Their lips are together, and their teeth are either touching or close together.
Over time, people who practice mewing train their bodies to naturally return to this position.
They refer to this as proper tongue posture.
Theory of How Mewing Works
According to English orthodontists Dr. John Mew, who originated this technique in the 1970s, and Dr. Mike Mew, his son and the person perhaps best know for the approach, people today have smaller jaws than our ancestors. They credit this environmental and lifestyle factors, like allergies that lead to mouth breathing and ready access to food that’s soft and easy to chew.
A smaller jaw leaves teeth crowded, and thus crooked. It also contributes to a less aesthetically pleasing face, the Mews say.
The two argue that practicing mewing can fix this by realigning the teeth and making the jaw larger, stronger, and more squared.
They also say that this change in tongue position can help correct a myriad of issues, including sleep apnea.
Is Mewing Really Effective?
There’s little objective evidence that mewing will change your face. In addition, there has been no credible, peer-reviewed study about the effects of mewing.
John Mew has said that his own children are evidence. His daughter, fed with soft foods until she was a 4-year-old and not taught mewing, had crooked teeth and poor facial alignment. Mike Mew, on the other hand, was taught mewing and to eat rough foods, and has a square, muscular jaw.
All of that said, there is some truth to the issues that the Mews raise. Research shows that human jaws are in fact getting smaller.4 This has been linked with health issues including crooked teeth, mouth breathing, and sleep apnea.
Researchers have indeed linked “oral posture”—the position of the teeth and tongue—to jaw development.4 The solutions that researchers propose are not unlike those for which the Mews advocate.
Researchers say that eating tougher foods—particularly in childhood—can help to develop the jaw, as can chewing gum. They also advise breathing and swallowing exercises to promote improved jaw development in children.