How can I stop chewing on things when I’m stressed?

Many of us have found ourselves chewing on the back of our pen while we’re deep in thought or gnawing on a hangnail when we’re feeling stressed out and overwhelmed. But if you’re constantly finding yourself chewing on things during moments of anxiety, even to the point where you’re causing injuries or damage to your teeth, nails, the inside of your mouth, or objects, it might be a sign that something more serious is going on. 

Stress-induced chewing can have many different explanations. In and of itself, the act of chewing itself is a natural stress reliever, and some research even points to the idea that chewing may help reduce hormone levels associated with stress. 

As a result, many people catch themselves mindlessly chewing on gum, their nails, or the drawstring of their hoodie when they are feeling heightened levels of anxiety. But if you are experiencing extreme or even seemingly uncontrollable urges to chew, there might be other potential explanations, including a possible tic or body-focused repetitive behavior (BFRB). 

Tics are largely involuntary movements or vocalizations that are most frequently associated with tic disorders or Tourette syndrome, while BFRBs are repetitive grooming behaviors that are voluntary but hard to resist. In both cases, stress and anxiety can make the behaviors worse, and this can sometimes cause damage to your teeth, mouth, self esteem, and comfort in social settings. 

In this article, we’ll discuss tics and BFRBs and how they might relate to your urge to chew on things when you are stressed. We’ll also discuss Habit Reversal Training (HRT), and how it can help in both cases of tics and BFRBs. 

Understanding stress-induced chewing as a tic

Tics are automatic, involuntary, and repetitive movements or verbalizations that are neurologically driven. Tics are most commonly associated with Tourette syndrome, a neurological condition that involves long-term motor and vocal tics. However, the DSM-5 also recognizes other tic disorders like persistent motor or vocal tic disorder and provisional tic disorder. These different disorders are diagnosed by the frequency and types of tics that a person experiences. 

Tics can look like many different things and are divided into two main categories: vocal tics and motor tics. Common examples of tics include involuntary shrugging, grunting, blinking, grimacing, sniffing, or clicking noises. 

People with tics often report feeling a premonitory urge, or an unpleasant feeling of some kind, right before they are about to tic, which can be compared to the irresistible feeling that you get right before you sneeze. Performing the movement or vocalization relieves that feeling. These premonitory urges can be repetitive and frequent, leading to frequent and involuntary tics. 

In addition to the common motor and vocal tics, some people with tic disorders can also have different variations of biting tics. For example, some people with tics may involuntarily bite their lips. Additionally, there have also been some cases in which people feel a premonitory urge of an “itchy tongue” that precedes the tic of biting their tongues.   

So what does this have to do with stress? As it turns out, heightened emotional states are very closely tied to tics. While someone with a tic disorder may tic at any time, it can become significantly worse if the person with the tic disorder is anxious. Several studies have indicated that many people who report having tic behaviors say that their involuntary movements and behaviors become worse with anxiety and stress. As a result, someone with a biting tic might find themselves involuntarily biting more often during times that they are stressed, anxious, or even excited. Tics can also become worse with fatigue or low sleep.

Understanding body-focused repetitive behaviors (BFRBs) 

Body-focused repetitive behaviors, or BFRBs for short, are similar to tics in that they are repetitive movements that are often preceded by a premonitory urge. Unlike tics, however, BFRBs are a voluntary behavior (even though they may not feel quite that way for some people who struggle with them). 

“In most cases, people with BFRBs can acknowledge that this behavior feels very much like something they need to engage in, but they can identify that it is, to some extent, a choice,” explains Dr. Mia Nuñez, licensed clinical psychologist and Regional Clinical Director at NOCD. “They can make the decision to start or stop, even if it’s very, very difficult.” Tics, however, are almost completely involuntary. 

Additionally, BFRBs always involve body-focused movements, while tics and other forms of stress chewing can include chewing of other items. BFRBs can be described as compulsive and repetitive grooming behaviors since they involve your own body parts. Some common examples of BFRBs include: 

• Trichotillomania, or hair pulling
• Excoriation, or skin picking

Some people may also deal with BFRBs that cause them to chew on their own cheeks, nails, tongue, or other body parts in a repetitive manner. A constant urge to chew on your nails, for example, is a BFRB called onychophagia, while skin biting is known as dermatophagia. BFRBs can also take the form of tongue biting, cheek biting, or any other repetitive chewing of your own body parts. 

BFRBs are almost always in response to stress, which may explain why someone who has a hard time with chewing or biting might see the problem become worse during moments when they are in a heightened state of distress. However, they can also be related to other internal emotions or environmental stressors like sadness or even just boredom. 

The consequences of stress-induced chewing

Occasional chewing of your own body or inanimate objects can seem innocuous enough, but if you’re doing it to the point that you’re concerned you might be dealing with a tic or a BFRB, the long-term consequences on your health can be severe. 

First and foremost, excessive chewing can be very bad for your teeth. Chewing on hard objects like pens and pencils can damage the enamel on your teeth. Enough chewing can cause cracks or chips, leaving you more susceptible to tooth sensitivity. At worst, excessive chewing of objects can even lead to serious oral injuries like fractures or even total breaks in your teeth.   

You can also cause injuries to other areas of your body depending on what you’re choosing to chew. For example, chewing on your nails can cause serious damage to the tissues of your nailbed, sometimes to the point where the damage is irreversible. It can also increase your risk of ingesting bacteria, as is also true if you’re chewing on household objects, or you may run the risk of introducing pathogenic bacteria and fungal infections to your nailbeds. If you prefer chewing on your lips and gums, you might also damage the soft tissue in your mouth, leading to lesions, scarring, and other serious injuries. 

Recovering through Habit Reversal Training (HRT) 

For people who are used to chewing as a form of self-soothing, it can feel overwhelming to break the habit. It’s especially hard if you feel like your chewing behaviors are involuntary and out of control, as might be the case for people who struggle with tics or BFRBs. However, the good news is that both tics and BFRBs can be treated effectively with a specific, specialized form of therapy called habit reversal training (HRT).  

HRT is a type of cognitive behavioral therapy that is used to effectively treat habitual behaviors in both tic disorders and BFRBs. HRT can look slightly different depending on whether you’re dealing with a tic disorder or a BFRB. However, the general approach for both conditions involves bringing awareness to the circumstances that lead to unwanted behaviors (in this case, chewing), and then introducing competing responses as an alternative. This approach works very well for compulsive and/or habitual behaviors, as is the case with BFRBs, but it also allows people with tics to better recognize their premonitory urges and gain greater control over how they respond to them. 

“HRT is about building awareness of the behavior to the point where you’re able to detect when you’re going to engage in the behavior,” explains Dr. Nuñez. “Along with that, it involves identifying things in your environment that are likely to trigger and reinforce the behavior. Some of those you can control to make it easier to resist behaviors. Others you can’t, but you can become aware of them.” 

She continues, “As awareness grows, you teach somebody a competing response, which is something else that you do instead of engaging in the behavior. Ideally, a competing response is going to serve a few different functions—some of the most important being that it actually prevents or inhibits your ability to engage in the behavior.” 

She goes on to outline an example in which someone has a problem picking at their skin (excoriation) or pulling at their hair (excoriation), both of which are BFRBs. In cases like these, a competing response might be to hold your teeth so they are lightly touching each other or to keep your mouth slightly open while breathing, and if chewing or biting is happening during sleep, a mouth guard might be used to help prevent further damage. “The idea is to choose to engage in the competing response instead and rewire your brain to go to the competing response rather than to the BFRB or tic until it becomes second nature.” 

HRT has been proven to be a very effective treatment approach for both tics and BFRBs. Studies have found that HRT was able to reduce tic severity by an average of 32.3%, which was more effective than supportive psychotherapy. Similarly, plenty of evidence suggests that HRT is highly effective for BFRBs like thumb sucking and nail biting. 

Getting help

Stress-induced chewing can stem from a variety of underlying causes, from boredom or nervous habits to more serious mental health conditions like tic disorders or BFRBs. 

If you’re concerned that you may be dealing with a tic or BFRB, and if your chewing is getting out of hand and impacting your life, the good news is that there is help available out there for you. NOCD’s entire, broad network of licensed therapists are trained in managing behaviors like tics and BFRBs through HRT, which can help you become aware of and actively resist harmful behaviors that can feel hopeless and out of your control. If you are interested in exploring how NOCD can help you, I encourage you to learn about NOCD’s accessible, evidence-based approach to treatment and match with the right clinician for your needs. 

In addition to HRT treatment, there are also some practical ways that you can discourage yourself from chewing objects to the detriment of your teeth, skin, and gums. These every day habits can help bring awareness to your chewing habits no matter where they stem from. Some ideas include: 

• Redirecting your nervous energy to fidgeting with your hands, like with dedicated fidget toys, focus tools, or stress balls  
• If you struggle with nail-biting and/or hangnail chewing, invest in manicures and nail treatments to discourage mindless chewing; there are also bitter tasting nail treatments you can put on your nails as well to discourage biting
• Bandaging the area that you like to chew on to protect it and bring awareness and mindfulness to an otherwise mindless habit 
• Switching to chewing gum rather than chewing hard objects that can damage your teeth 
• Practicing managing your stress with healthy habits like mindfulness practice, daily exercise, and taking frequent breaks when you recognize your stress levels are getting too high 

Ultimately, no matter where your stress-induced chewing habits are coming from, there are many different avenues for you to get help and break a potentially damaging habit. By improving your mindfulness around the habit, redirecting that nervous energy to other places, and getting help from a mental health professional if needed, you can tackle your chewing problem and keep yourself healthy.