How Do Chew Necklaces Work?

Last updated: 12 April 2026 · Chewel

Chew necklaces work by providing oral proprioceptive input — the deep, rhythmic pressure that comes from engaging the jaw muscles. This input signals to the brain and nervous system in ways that appear to support attention, reduce arousal when it is too high, and increase it when it is too low. Research suggests chewing improves sustained attention and reduces stress hormones in students.

Step One: Proprioception — The Body Sense

Most people know five senses: sight, hearing, smell, taste, and touch. But there are more. Proprioception is the body's sense of its own position and movement — sometimes called the "hidden sense." It tells your brain where your limbs are without you having to look. It is the sense that lets you touch your nose with your eyes closed.

Proprioceptive signals come from specialised receptors in muscles, tendons, and joints. When these receptors are activated — by movement, pressure, or resistance — they send signals to the brain via the nervous system. These signals play a major role in sensory regulation: the process by which the nervous system balances arousal and calm.

The jaw contains some of the most powerful proprioceptive receptors in the body. The muscles of mastication (chewing) are among the strongest in the human body relative to their size. When you chew, you activate a dense network of proprioceptive receptors that send a rich stream of signals to the brainstem and cortex.

See also: what is proprioception?

The Reticular Activating System and Arousal

The reticular activating system (RAS) is a network of neurons in the brainstem that regulates wakefulness, arousal, and transitions between states of alertness. It acts as a gatekeeper for sensory information, filtering out background noise and helping the brain attend to what matters.

The RAS is sensitive to proprioceptive input. Research in sensory integration theory (Ayres 1972) suggests that proprioceptive input — including that from the jaw — has a modulating effect on the RAS: it can increase arousal when a person is under-stimulated, and calm arousal when a person is over-stimulated. This bidirectional effect makes proprioception uniquely valuable as a self-regulation tool.

The Yerkes-Dodson Curve

The Yerkes-Dodson law describes the relationship between arousal and performance. It follows an inverted U shape: performance is poorest at very low arousal (drowsy, inattentive) and very high arousal (anxious, overwhelmed), and is best at a moderate, optimal level.

For children with ADHD, autism, or sensory processing differences, it can be particularly difficult to find and maintain this optimal zone. A child who is under-aroused may appear to daydream or switch off. A child who is over-aroused may appear restless, impulsive, or difficult to settle. Proprioceptive input — including chewing — is one of the most reliable tools occupational therapists use to shift arousal toward the optimal zone.

The Vagus Nerve Connection

The vagus nerve is the longest cranial nerve in the body, running from the brainstem to the abdomen. It is the primary pathway of the parasympathetic nervous system — the "rest and digest" or calming system. Vagal tone (the activity of the vagus nerve) is associated with emotional regulation, stress resilience, and attention.

Chewing activates the muscles of mastication, which are innervated by the trigeminal nerve. The trigeminal nerve has strong connections to the vagal complex. Some researchers propose that rhythmic chewing stimulates vagal tone — essentially giving the calming system a boost. This may partly explain why people instinctively chew when stressed or concentrating: it activates the body's own calming pathway.

What Does the Research Say?

Hirano et al. (2015) — Sustained Attention

A study published in Brain & Cognition (Hirano et al., 2015) found that chewing a piece of gum during a sustained attention task improved performance on measures of attention and reaction time. Participants who chewed showed faster and more accurate responses compared to non-chewing conditions. Brain imaging suggested increased activity in areas associated with attention and arousal during chewing.

Miquel et al. (2019) — Meta-Analysis

A systematic review and meta-analysis by Miquel et al. (2019) examined 15 randomised controlled trials on the effects of chewing gum on cognition and mood. The review concluded that chewing produced statistically significant benefits to attention, memory, and mood. The effects were modest but consistent across studies — suggesting a real, if small, effect.

Yaman-Sözbir et al. (2019) — Stress and Exam Performance

This study examined university students during examination periods. Students who chewed gum during exams had significantly lower salivary cortisol levels — a biological marker of stress — and achieved higher scores than those who did not. The researchers concluded that chewing may help manage exam-related stress and support academic performance.

Does This Mean Chewing Always Helps?

No — and it is important to be nuanced here. The research on chewing is most relevant to people who need the input: those with lower arousal, difficulty sustaining attention, or elevated stress. For someone who is already calm and well-focused, chewing is unlikely to produce dramatic effects.

The children and adults who benefit most from chew necklaces are those who are sensory seeking — actively looking for oral input — and for whom alternative sources of that input (nail biting, clothing, pencils) are problematic. For these individuals, a chew necklace provides the right input in a safe, hygienic, and socially acceptable way.