What Happens If You Bite a Pencil? The Surprising Health Risks

October 1, 2025 •

4 min read

While it's a common nervous habit, a 2018 Delta Dental survey revealed that nearly a quarter of adults report chewing on pens or pencils. So, what happens if you bite a pencil? The seemingly harmless habit can have serious consequences for your oral and overall health.

Quick Summary

Biting a pencil can lead to chipped or fractured teeth, premature enamel wear, and jaw issues like TMD. This unhygienic habit also introduces harmful bacteria from the pencil's surface into your mouth, posing a significant infection risk beyond just cosmetic damage.

Key Points

Dental Damage: Habitual pencil chewing can cause chipped or cracked teeth, enamel wear, and damage to existing dental work like fillings and crowns.
Infection Risk: Pencils are covered in germs from everyday use. Putting them in your mouth introduces harmful bacteria and viruses that can cause illness.
Jaw Pain (TMJ): Repetitive chewing on a hard object can strain the temporomandibular joint, leading to headaches, jaw pain, and other symptoms associated with TMD.
Anxiety Indicator: The habit is often a physical manifestation of stress or anxiety. Addressing the underlying psychological cause is key to stopping the behavior.
Non-Toxic Core: Modern pencils use non-toxic graphite, not lead. However, the external paint, lacquer, and other materials are still not safe for ingestion.

The Hidden Dangers to Your Dental Health

Biting down on a hard object like a pencil subjects your teeth to immense pressure they are not designed to withstand. This can lead to a variety of dental problems, from minor cosmetic damage to major structural issues that require costly dental work to fix.

Tooth Fractures and Chipping

The most immediate risk of biting a pencil is a chipped or cracked tooth. The hard wood and graphite core can cause stress fractures in your enamel, especially if you have pre-existing fillings or weak spots. These fractures can run deep, sometimes extending to the root of the tooth, which can be extremely painful and may require a root canal or extraction.

Premature Enamel Wear

Your tooth enamel is the strongest substance in your body, but repetitive chewing on a hard, non-food item acts like a slow-motion grinding process. Over time, this wears down the protective enamel, leaving the more sensitive dentin layer exposed. This can result in increased tooth sensitivity to hot and cold temperatures.

Damage to Existing Dental Work

If you have crowns, veneers, fillings, or braces, biting a pencil is an especially bad idea. The constant pressure can chip or dislodge dental work, leading to an expensive and inconvenient trip to the dentist. Braces can be bent or broken, and the brackets can pop off, extending your treatment time.

Oral Hygiene and Infection Risks

Pencils are not sterile. They roll around on desks, floors, and in bags, picking up a plethora of bacteria and viruses. Putting one in your mouth is a direct line for these pathogens to enter your body.

Bacterial Contamination

Numerous studies have shown that everyday office and school supplies harbor more bacteria than a toilet seat. Common pathogens like E. coli and staphylococcus can live on a pencil's surface for weeks, making it a serious vector for illness. A compromised immune system makes this risk even more significant.

Ingesting Potentially Harmful Chemicals

While modern pencils contain a non-toxic graphite core (we will discuss this misconception later), the exterior is coated in paint and lacquer. The glue that holds the pencil together and the metal ferrule on the end are also not meant for human consumption. While a tiny amount won't cause immediate harm, habitually ingesting these chemicals can lead to a buildup of toxins over time.

Choking Hazards

This is a particular danger for children, but it can happen to anyone. Small, sharp splinters of wood or a broken piece of the metal ferrule can break off and be accidentally swallowed. These sharp objects can pose a choking hazard or, in rare cases, cause internal injury if they get lodged in the digestive tract.

The Link to Your Jaw Health (TMJ)

The temporomandibular joint (TMJ) connects your jawbone to your skull. Repetitive, uneven chewing on one side of your mouth can put excessive stress on this joint and the surrounding muscles. Over time, this can lead to:

Jaw pain and tenderness
Headaches and earaches
Aches and pain in or around your ear
Difficulty or pain while chewing
Aching facial pain

The Non-Toxicity of Graphite: Debunking the “Lead” Myth

One of the most persistent myths is that pencils contain lead. This is not true and hasn't been since the 19th century. Below is a comparison of graphite and actual lead.


Feature	Pencil Graphite	Element Lead (Pb)
Composition	Carbon (allotrope)	Soft, heavy metal
Toxicity	Minimally toxic	Highly toxic neurotoxin
Appearance	Black, soft, flaky	Grayish-blue, malleable
Uses	Pencils, lubricants	Batteries, shielding
Ingestion	Unlikely to cause harm	Severe lead poisoning

Psychological Reasons Behind the Habit

Many people bite pencils as a coping mechanism for anxiety, stress, or to aid concentration. Addressing the underlying psychological trigger is often the most effective way to break the habit permanently. Consulting with a therapist or counselor can help identify these triggers and develop healthier coping strategies.

How to Break the Habit of Biting Pencils

Breaking a deeply ingrained habit requires a multi-pronged approach. Here are several techniques you can try:

Use a Replacement: Chew sugar-free gum, suck on a mint, or keep a reusable chewing device designed for oral fixation. The sensory input can satisfy the need to chew without harming your teeth.
Use Mindful Awareness: When you find yourself reaching for the pencil, stop and pay attention to what you are doing. Simply being aware of the action can help you interrupt the cycle.
Find a Stress Reliever: If anxiety is the root cause, find a different outlet. Try a stress ball, a fidget spinner, or take a short walk to clear your head.
Try Aversive Conditioning: Paint the end of your pencil with bitter-tasting nail polish. The unpleasant taste will serve as a negative reinforcement to stop the habit.
Address Underlying Issues: If you suspect the habit is linked to anxiety or stress, consider talking to a medical professional. As described on the American Dental Association website, addressing the root cause is crucial for lasting change.

Conclusion: Prioritize Your Oral Health

While biting a pencil might seem like a small, harmless action, the cumulative effects can lead to significant dental and health issues. From chipped teeth and enamel wear to bacterial exposure and TMJ problems, the risks are not worth it. By understanding the underlying reasons and employing alternative coping strategies, you can protect your smile and improve your overall well-being.

Frequently Asked Questions

No, this is a common myth. Pencils have been made with non-toxic graphite and clay since the 19th century. The term 'pencil lead' is an outdated holdover from when people believed the dark mineral was related to lead.

Yes, it can. Repeated chewing can cause stress fractures in tooth enamel, leading to irreversible damage and increased sensitivity. It can also cause chips or breakages that require dental repair.

Effective alternatives include chewing sugar-free gum, keeping a water bottle nearby to sip from, or using stress relievers like a fidget toy or stress ball to occupy your hands and mind.

In most cases, a tiny piece of wood or graphite will pass through your system without issue. However, if you swallow a large or sharp piece, experience pain, or have difficulty breathing, you should seek immediate medical attention. It is always wise to consult a medical professional for guidance.

It is possible. Chewing on hard objects like pencils can put strain on your temporomandibular joint (TMJ), which can lead to jaw pain, soreness, headaches, and other symptoms. If you experience chronic jaw pain, consult a dentist or doctor.

For many, yes. Chewing can be a self-soothing mechanism to cope with stress or anxiety. It can be helpful to address the underlying psychological cause with a professional, who can help you find healthier coping strategies.

Most modern pencils use non-toxic paint, but it is not intended for human consumption. Repeatedly ingesting paint, lacquer, and glue can lead to a buildup of unwanted chemicals in your body over time, so it's best to avoid it.