You may have noticed a new Instagram workout trend meant to target a specific area of your body: your face.
But does it work?
Jawzrsize, a product marketed as a way to exercise the muscles in your face to achieve the "elusive perfect jaw," makes it seem that way. However, if you're really trying to slim down your jaw, science isn't on your side.
Jawzrsize was invented by a former mixed martial arts fighter Brandon Harris.
There are nearly 200 posts on Instagram about the product, and many of the pictures are promotional material of people using it.
ATTN: reached out to Harris about the claims in his product's advertisements, but he did not comment before this story was published.
Jawzrsize isn't the only face workout on the market.
Japan's Facial Fitness Pao made U.S. headlines in 2014, mostly for it's unusual commercial promoting a "30 second workout for the muscles around the mouth."
But will face exercises make your face look slimmer?
ATTN: talked to Jonathan Ross, a senior consultant on personal training at the American Council on Exercise about exercises for the face. If you're trying to lose weight in your face, Jawzrsize or any other facial exercise wont help you, he explained, because it's not actually possible to target a specific body part for weight loss.
"Our circulatory system connects all parts of our body to all the other parts," Ross said. "When fat is released into the blood stream for use as energy, it is done so a little bit from everywhere in proportion to how much is there, and once it hits the blood stream it circulates to the working muscles. Hand exercises will not yield skinny fingers."
Ross also said that it's not possible to tone the muscles in your face so it appears slimmer, only losing weight throughout your body can do that.
"The muscle underneath can be developed or not, yet what determines appearance is the body fat beneath the skin. If one has reduced body fat enough that the muscles below show through, then there will be more of a toned appearance," he said. "However, the muscles of the jaw and neck are small enough that when properly toned, they would not make a big visual impact like bulging biceps, nor would most people find that look appealing."
He said that face and jaw exercises don't pose any obvious safety risks but they probably aren't needed. "There’s very little inherent risk in doing the exercises," he said. "However, if someone is eating and chewing normal food a normal number of times, these exercises are unnecessary."
Face exercises aren't new.
Fitness expert Jack LaLanne, who died in 2011 at the age of 96, became famous for giving fitness advice on American televisions from the 1950s to the 1970s. He promoted a "beauty treatment" facial workout.
"You know why so many of you students look older than your years? And why your jowls are hanging, and your chin is hanging, and your neck looks kind of craggy looking you know? And your eyes, you've got all kinds of wrinkles around your eyes?," LaLanne asked in a vintage video published by BBC News after this death. "Because the muscles are out of shape. And you can firm up your stomach by exercise, [so] you can firm up the muscles in the face."