On June 28, researchers in the United Kingdom and New Zealand announced the invention of DentalSlim Diet Control, a new intra-oral locking device reminiscent of an archaic torture mechanism. Its two magnetic pieces are designed to prevent a person’s jaw from opening by more than 2 millimeters—a distance the creators said “allows free speech and doesn’t restrict breathing.” The goal, per the project’s researchers, is to combat obesity by limiting wearers to a liquid-only diet.
“The main barrier for people for successful weight loss is compliance and this helps them establish new habits, allowing them to comply with a low-calorie diet for a period of time. It really kick-starts the process,” said Paul Brunton, the lead researcher, in a press release.
“It is a non-invasive, reversible, economical and attractive alternative to surgical procedure,” he continued. “The fact is, there are no adverse consequences with this device.”
A number of dieticians and other medical professionals vehemently disagree.
“This device is medieval and barbaric,” said Lauren Cadillac, a New York–based registered dietician, over email. “I was shocked to see something like this come out in 2021. When I first saw a post about the device, I thought the post was satire or was referencing something from the 80s. Honestly I think it’s one of the dumbest things I’ve seen in a long time.”
“I thought it was a joke, honestly,” said Andrea Mathis, another dietician interviewed by Slate and the creator of Beautiful Eats and Things, a platform dedicated to realistic nutrition and wellness. “I thought, ‘This is not real. This is just a joke just to kind of get people riled up.’ ”
“I don’t even know how people would speak comfortably, or laugh, or brush their teeth—so many important, wonderful things that we do with our mouth would be so limited,” said Tanya Freirich, a New York–based dietician and nutritionist.
The device’s existence speaks to society’s objections to fat people simply existing, and it relays a clear message: that fat bodies are a problem needing fixing by whatever means necessary. To forcibly close a person’s mouth for the sake of weight loss is a crude yet long-established practice, a physical expression of the premise that fat people have inadequate willpower. The standard defense of these studies is that losing weight is good for people classified as “morbidly obese” and that the participants are willing to do it—as if everyone hasn’t internalized fatphobia to an extent, or the desire to be small isn’t that pervasive, or life isn’t incredibly easier for thin folks.
“When someone is in a larger body and they’re content, they’re enjoying life, I feel like it’s a problem,” said Mathis. “Someone is always going to give advice on how they should lose weight, how they should eat healthier. They’re going to bring out this new device and say, ‘Hey, maybe you should try this.’ ”
During the clinical trials for the DentalSlim device, seven healthy fat women were restricted to a 1,200 calorie diet, which fulfills the caloric needs of a toddler. A spokesperson for the University of Otago, where Brunton is a professor, sent Slate a statement assuring the safety and effectiveness of the product for those seeking to lose weight before surgery. Brunton, who is quoted in the statement, said he figures the device will be used mostly by people pre-surgery.
“Many patients who are severely overweight find themselves being told they are not able to have surgery until they lose weight because it is not safe for them to be put under general anaesthetic; and that can be for any surgery such as hip replacement or kidney stone removal for example,” he said in the statement. “It’s important to note that this device is simply a tool available for those who want it. People will not be forced to use it—it’s a choice—and it’s a decision that a person would be able to make for themselves in consultation with medical professionals.”
The statement adds that participants “were all motivated to continue their weight loss journey after the device was removed.” It also notes that the university has gotten a spike of support and inquiries into the product, despite the backlash.
Reasoning about whether someone should lose weight before surgery is based on a 30-year-old guideline from the National Institutes of Health. When it comes to bariatric operations, losing weight beforehand is used to indicate whether a patient can actually attain and maintain an extreme amount of weight loss. Insurance companies typically require patients to do so before they undergo bariatric surgery. The American Society for Metabolic and Bariatric Surgery denounced the practice in 2019, and a study from that year found that losing weight beforehand might cause surgical complications—if it does anything at all.
“In my opinion, it is unethical,” Cadillac said. “We have a large body of research showing intentional weight loss diets not only don’t work, but cause harm in the long run. By going on a low-calorie diet, you are depleting your body of vital nutrients—nutrients needed for wound healing and recovery. It makes no sense to starve a human to prepare them for surgery. It sets them up for poorer outcomes.”
Low-calorie liquid-only diets have a long history of ineffectiveness, with or without accompanying jaw restraints, and they have been found to produce adverse results including, but not limited to:
• Nutrient deficiencies, which can lead to hair loss, dizziness, heart damage, fatigue, gallstones, and more.
• Constipation from a lack of sufficient fiber, since all of someone’s food is liquified.
• Loss of muscle mass, which can slow the metabolism.
• Faster digestion, which can cause spikes and dips in blood sugar. (“It’s sending your blood sugar kind of on a roller coaster. So you get a little bit of sugar high, a burst of energy, but then you’re going to crash and feel very tired. Maybe get a headache,” explained Freirich.)
If someone were extremely meticulous, Freirich said, they could technically get all the nutrition they needed through liquids. It would be unsatisfying, though, since satiety is aided by chewing solid foods.
“This is not enough energy for any adult human and is therefore dangerous and unsustainable,” said Cadillac of the low-calorie diet employed by researchers. “The study even states after the device is removed, weight gain occurred. This sets the user up for weight regain and yo-yo dieting, which is associated with heart disease and premature death.”
Between 1970 and 1990, there was a boom in research surrounding jaw wiring for weight loss in those whom researchers deemed to be “extremely obese.” Some of those studies are, honestly, a bit absurd. One study from 1977 restricted participants to an 800 calorie a day diet of tomato juice, milk, and unsweetened fruit juices alongside a medley of supplements to counteract the inevitable nutrient deficiencies. Another study, published in 1981, is a bit more harrowing. Participants’ jaws were wired shut for six to 12 months in order to make them lose weight so that researchers could then test whether tying a nylon cord around their waists would stop them from gaining it back. During the jaw-wiring period, the participants relied on two pints of milk, a multivitamin, and another daily supplement for sustenance. Once the wiring was removed, the control group went on to regain weight, while the experimental group did not, because, researchers concluded, the cord tied around them served as “a psychological barrier to weight gain.” (An honorable mention outside that time frame goes to a device from the early aughts that was designed to make the mouth smaller and limit how much food people could consume.)
Most participants ended up regaining at least a portion of the weight they lost in the two studies mentioned and several others reviewed by Slate. The studies reviewed also don’t delve into the mental and emotional toll of having your mouth wired shut for months on end. Food is a joy that brings people together. Many memories and much of our socialization occurs around food. To wire someone’s jaw shut is to rob them of it.
“You’re taking something away from your life that brings you joy, and that can cause lots of mental issues for someone whether it’s anxiety or depression,” said Mathis.
“They can forget what it means to enjoy food. They can forget what it means to listen to your body,” she added. “And that’s just a dangerous cycle.”
It also doesn’t do anything to improve someone’s relationship with food. The dieticians who spoke with Slate all agreed that this device and diet combo could set someone up to enter a cycle of restriction and binge eating or develop a damaged body image, a poor relationship to food, disordered eating, or an eating disorder. And this is a particularly perilous situation for participants who already suffer from these ailments.
“This device is designed to fail,” Cadillac said of the DentalSlim. “Anyone consuming 1,200 calories will lose weight initially, but will inevitably gain it all back. Diet culture has taught us that when we regain the weight, it is our fault, when in reality, it happens because diets don’t work. When individuals inevitably gain the weight back, it will likely lead to feelings of guilt and shame and contribute to a poor negative body image.”
Diet culture’s ethos of self-control as the “cure” for fatness is certainly one of the main culprits here, and the device is a conduit of that belief. For Black people who exist in larger bodies, this presents a specific issue, said Mathis. Writer Chrissy King, in a broad, and persuasive, article discussing the role racism plays in diet culture, points to the research of Sabrina Strings.
“One of the things that the colonists believed was that Black people were inherently more sensuous, that people love sex and they love food, and so the idea was that Black people had more venereal diseases and that Black people were inherently obese because they lack self-control,” wrote Strings. “And of course, self-control and rationality, after the Enlightenment, were characteristics that were deemed integral to whiteness.”
When this is coupled with how larger bodies are discussed, food apartheid, the overwhelming whiteness of dietitians, cultural foods being written off as unhealthy, and the apathy most physicians direct at their Black patients, it makes one wonder who is more likely to be encouraged to use the DentalSlim device—at least in the U.S.
“Black people who are in larger bodies … we already are judged based on what we look like instead of them listening to the actual health concern,” said Mathis. “It’s like, you know, ‘You’re overweight, so this must be the issue for your cold or for your flu symptoms.’ So I feel that doctors would possibly recommend this device to Black people who are in larger bodies because they’re thinking that the weight is really the issue for every single health complication that they could possibly have.”