We’ve all heard of exercising to make muscles bigger and more defined, but have you heard of working out your jaw? Tongue mewing, one of the latest online trends, claims that you can change the shape of your jawline by focusing on the placement of your tongue within your mouth.

Named for British orthodontist Dr. John Mew, tongue mewing is the practice of pushing out your jaw and relaxing and flattening your tongue against the roof of your mouth. Named for British orthodontist Dr. John Mew, proponents of tongue mewing claim that mewing realigns your teeth and makes your jaw larger and stronger and gives it a more squared-off appearance. They also claim that mewing helps treat sleep apnea, sinusitis, snoring, jaw pain and other issues.

However, the American Association of Orthodontists has not endorsed tongue mewing as an effective way to change the shape of your jawline.

Your jaw is part of the very complex interactions between your face, head and neck. It’s impossible to change one part of this system without influencing the others. Possible negative side effects of tongue mewing include:

Our verdict: There’s no research to suggest that tongue mewing will make a meaningful difference in the appearance of your jawline, and there’s the possibility that practicing it may lead to needing dental treatment. If you decide you’d like to try it, be sure to discuss any changes to your oral health care routine with your dentist. He or she will be able to provide recommendations and the information you need to ensure a healthy smile.