Eating disorder charities slam jaw-locking ‘weight loss device’ invented by scientists

Eating disorder charities slam jaw-locking ‘weight loss device’ invented by scientists
Magnetic device stops users from opening their mouths more than 2mm wide, forcing them to stick to liquid diets

Eating disorder charities have lambasted a “world-first weight-loss device” developed by researchers that prevents people from opening their mouths properly, forcing them to stick to liquid diets.

The device, called the DentalSlim Diet Control, uses magnets that are “cemented” to a person’s teeth to restrict the mouth from opening more than 2mm wide. According to the university, it restricts the wearer “to a liquid diet, but it allows free speech and doesn’t restrict breathing”.

Researchers from the University of Ontago, New Zealand, said that the participants in their trial wore the intra-oral device for two weeks and lost an average of 6.36kg, adding that they were “motivated to continue with their weight loss journey”.

The device is fitted by a dentist to the upper and lower back teeth and uses magnets “with unique custom-manufactured locking bolts”. It can be released by the user in case of an emergency, said the researchers.

But the tool garnered fierce backlash online and from eating disorder charities, who said it “oversimplifies the issue of obesity”. It comes after lead researcher Professor Paul Brunton insisted the device is an “effective, safe and affordable tool for people battling obesity”.

Prof Brunton, the pro-vice-chancellor of the University of Otago Health Sciences department, said in a statement: “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.”

He emphasised that the device is “non-invasive, economical and [an] attractive alternative to surgical procedures, adding: “The fact is, there are no adverse consequences with this device.”

Deanne Jade, founder and principal of the National Centre for Eating Disorders (NCFED), disagreed, describing the contraption as “heinous”.

She told The Independent: “When we talk about weight loss, we’re not talking about something that prevents you from putting food in your mouth. We’re looking for changes in mindset, lifestyle, skills and strategies that people need to learn in order to change their relationship with food for life.

“I can’t for the life of me see how a tool like this is going to create the commitment needed for a sustained change.”

She added that the device was akin to “going back to the dark ages in disguise”, referring to the practice of wiring people’s jaws shut to prevent a person from being able to consume solid food in order to lose weight. Jaw wiring was originally used to fix the jaw in place while a fracture heals.

According to the researchers, jaw wiring was a “popular” method in the 1980s, but involved risks including the danger of choking on vomit and the development of gum disease.

Prof Brunton said: “The beauty of [the DentalSlim Diet Control device] is that once patients are fitted with the device, after two or three weeks they can have the magnets disengaged.

“They could then have a period with a less restricted diet and then go back into treatment. This would allow for a phased approach to weight loss supported by advice from a dietitian allowing long-term weight loss goals to be realised.”

But Tom Quinn, director of external affairs at the UK’s leading eating disorder charity Beat, told The Independent: “It is incredibly concerning to read that this is a proposed solution to supporting someone with obesity. We know that many people living with obesity are also affected by binge eating disorder (BED), which often goes undiagnosed.

“Using such a device would be incredibly damaging to someone with BED and could cause serious harm, as BED is a serious mental illness which requires psychological treatment, with weight loss treatments often exacerbating symptoms.

“It also completely over-simplifies the issue of obesity, reduces the process of weight loss to a question of compliance and willpower and ignores the many complex factors involved, which may include eating disorders.”

The University of Otago issued a statement on Twitter to clarify that the device is “not intended as a quick or long-term weight loss tool; rather it is aimed to assist people who need to undergo surgery and who cannot have the surgery until they have lost weight”.

Gemma Oaten, charity manager and patron at Lancashire charity SEED (Support and Education for Eating Disorders), added: “We are living in a world where people are feeling vulnerable, scared and afraid, and a lot of that is manifesting itself in eating disorders.

“Now, the fact that a university has gone to the length to produce this and then share it on social media where all of the people who are struggling right now have access to it is only compounding the whole narrative that obesity is just a physical thing that needs addressing.

“News flash: people who are obese often have eating disorders or disordered eating. We know this all too well – it is a mental health illness. We can’t address the physical without addressing the mental health side of things as well.

“By fitting somebody with a contraption that locks their jaw, no matter what way or reason, whether it is to go for surgery because they need to lose weight before they do that, they need supporting mentally as well. That’s just horrific.”

The Independent has contacted the University of Otago for further comment.

For anyone struggling with the issues raised in this piece, eating disorder charity Beat’s helpline is available 365 days a year on 0808 801 0677.

NCFED offers information, resources and counselling for those suffering from eating disorders, as well as their support networks. Visit or call 0845 838 2040.

SEED is dedicated to raising awareness about eating disorders in Lancashire and the North West of England and are available via or call 01772 915735.