The Hidden Eating Disorder Behavior Ensnaring Millions of Teens

Raising awareness serves as the initial step toward aiding more individuals, especially teenagers. Heidi McLachlan, starting in her youth and spanning over two decades, grappled with a detrimental body image. Her relentless endeavors to prevent weight gain propelled her into a realm of disordered eating behaviors, including anorexia nervosa and chewing and spitting.

Chew and spit (CHSP) is a behavior involving the act of chewing food and then intentionally spitting it out, driven by the desire to derive pleasure from the taste without actually consuming the calories. For McLachlan, chewing and spitting began as a symptom of anorexia nervosa — just another one of several strategies she used to steer clear of calories.

Now recovered and a licensed eating disorder recovery coach based in Saskatoon, Canada, McLachlan has seen firsthand the significant attention and research eating disorders like anorexia and bulimia have received, and has become concerned that more people aren’t aware of chewing and spitting.

Other experts in the field of eating disorders have also noted similar patterns of chewing and spitting. Pediatrician and eating disorder specialist Jason Nagata reports that since the epidemic's onset, the number of teenagers admitted to UCSF Benioff Children's Hospital for eating disorders, including those who engage in the practice of chewing and spitting as a form of self-starvation, has doubled.

In a 2018 study conducted in Australia, it was revealed that 0.4 percent of adults, with a median age of 39, participate in the behavior of chewing and spitting. While that was a very small study that may capture only a fraction of the adults who actually do this, if we were to assume similar rates in the US and project that figure out over the 258 million adults living there, that figure would mean more than 1.3 million of them engage in chewing and spitting.

When considering a much larger study done the following year in Australia, things become very concerning. That one focused specifically on young people aged 11 to 19 and found the problem to be much more pervasive than previously thought. The study involved almost 5,000 children from 13 different schools, and found that 12% of those pupils regularly engaged in chewing and spitting.

Again, assuming similar rates in the US, this means that of the estimated 26.2 million children between the ages of 12 and 17 living in the US, it’s possible more than 3 million of them engage in the practice.

While the practice of chewing and spitting is less recognized than other forms of disordered eating, those who have suffered through it — or helped others who have — know it still causes harm.

James Greenblatt, chief medical officer at Walden Behavioral Care in Dedham, Massachusetts, and the author of Integrative Medicine for Binge Eating and Answers to Anorexia, explains that the behavior can cause gastrointestinal issues like acid reflux, stomach ulcers, and even excess weight. “Odd as it may seem, CHSP can indeed result in weight gain,” he says. “While researchers aren’t sure as to what drives the connection, some speculate that it’s due to the ‘cold turkey rebound effect,’ i.e., drastically restricting food drives a vicious hunger that, later on, causes the person to binge and ultimately consume a far greater number of calories.”

Perhaps most concerning is that the behavior can be a “gateway” step toward more dangerous eating disorders. "Individuals who participate in chewing and spitting behaviors face an elevated likelihood of developing an eating disorder," Nagata explains.

So why don’t we have more definitive answers to these questions? One explanation Greenblatt points to is that much of the research in mental health is driven by pharmaceutical incentive. Because “it is unlikely that there would be a medication to specifically address CHSP,” he says, “my concern is that future research [driven by the pharmaceutical industry] would be limited.”

Many experts point to another explanation for why we don’t know more: All US-based doctors who treat eating disorders turn to the same source of information, The Diagnostic and Statistical Manual of Mental Disorders, or DSM. The DSM is the authoritative guide used for matching patients with specific mental health diagnoses and for recommended treatments. In the latest edition of the DSM, known as DSM-5, chewing and spitting isn’t mentioned at all (though it still technically falls in the OSFED category). The OSFED category is where all known disordered eating behaviors or symptoms go until they have enough data to support their own classification or subtype definition — something only a handful of eating disorders have.

Increased awareness of the behavior and its consequences could be helpful. Experts believe it’s essential for those who engage in chewing and spitting to know they are not alone, and also to know this is a problem they can seek help for.

Until similar distinctions are established and additional data is collected, compiled, and presented for chewing and spitting, physicians can still diagnose and treat it as recommended in the DSM-5 OSFED category. In the meantime, more researchers could begin isolating existing CHSP data and seeking to answer some of the unanswered questions about the behavior. Such research “definitely should be” happening if for no other reason because doing so could lead to increased public awareness which could lead to more people seeking and getting the help they need.

Jennifer Wildes, director of the Eating Disorders Program at the University of Chicago Medicine, says "Individuals struggling with eating disorders like chewing and spitting often feel like they are the only ones struggling in this certain way. The more awareness there is that others struggle in this way too, the more we will see individuals reaching out for help.”