The simple act of chewing, or mastication, has a surprising number of physiological effects that can influence your state of mind. For decades, researchers have investigated the link between this rhythmic jaw movement and cognitive performance, with mounting evidence suggesting a positive connection. From students studying for exams to workers looking for an afternoon boost, the act of chewing is increasingly recognized as a potentially effective tool for enhancing focus and overall alertness.
How Mastication Affects the Brain
The improved alertness from chewing isn't just a placebo effect; it's rooted in verifiable physiological changes within the body and brain. The primary mechanisms identified by research include:
Increased Cerebral Blood Flow (CBF)
Chewing triggers an increase in heart rate and, subsequently, cerebral blood flow, delivering more oxygen and glucose to the brain. This fresh supply of nutrients to key brain regions, such as the prefrontal cortex and hippocampus, can enhance cognitive performance and contribute to a feeling of being more awake. One neuroimaging review in Frontiers in Systems Neuroscience specifically highlighted that chewing reliably engages sensorimotor circuits and enhances regional CBF.
Heightened Arousal and Attention
Chewing stimulates the trigeminal nerve, which innervates the jaw muscles. This stimulation is arousing and connects to the Ascending Reticular Activating System (ARAS) in the brain, a structure that plays a key role in regulating consciousness and alertness. This neural activation helps maintain vigilance, particularly during mentally demanding tasks.
Stress Reduction
For many, chewing acts as a calming, repetitive motion that can reduce levels of the stress hormone cortisol. A study on university students found that chewing gum for two weeks resulted in participants reporting less stress related to academic workload. By lowering stress and anxiety, chewing creates a more favorable mental state for focused work and learning.
Enhanced Memory
Some studies have indicated that chewing can improve aspects of memory, such as immediate and delayed recall. Researchers speculate this may be linked to the chewing-induced increase in heart rate and cerebral blood flow, though the full mechanism is not yet clear.
Influencing Factors for Chewing's Effects
Not all chewing experiences are created equal. Several factors can modulate the cognitive and physiological effects of mastication. These include the hardness of the chewing material, the flavor, and the duration of chewing.
| Chewing Material Comparison | Feature | Chewing Gum | Harder Materials (e.g., wood blocks in studies) |
|---|---|---|---|
| Effect on CBF | Increases cerebral blood flow to certain brain regions. | Also increases CBF, possibly to a greater extent with sustained chewing. | |
| Effect on Antioxidants | No significant change in brain antioxidant levels observed in one study. | Significantly elevates brain antioxidant (GSH) concentration, correlated with improved memory. | |
| Intensity/Force | Provides moderate, consistent chewing intensity. | Requires greater muscle force, which some studies suggest can intensify certain brain responses. | |
| Sustained Alertness | Effects are often short-lived and subside after chewing stops. | Can potentially offer more robust or longer-lasting cognitive effects due to higher force. |
Practical Applications of Chewing for Alertness
For Students
- Exam preparation: Chew gum while studying and during the exam. The act of chewing can help with memory recall through 'context reinstatement', linking the information to the act of chewing.
- Sustained attention: During long lectures or study sessions, chewing can combat mental fatigue and help maintain focus for longer periods.
For Workers
- Afternoon slump: A piece of gum can be a calorie-free alternative to sugary snacks or extra coffee to combat post-lunch drowsiness and boost focus.
- Stressful tasks: The stress-reducing effects of chewing can be beneficial before high-stakes meetings or during periods of intense work.
For Everyone
- Driving: When driving long distances, chewing can help maintain alertness and fight off drowsiness, though it is not a substitute for proper rest.
- Breaking habits: For those trying to quit smoking or reduce caffeine intake, chewing gum can satisfy the oral fixation and help manage cravings.
Considerations and Potential Drawbacks
While generally safe and effective, excessive chewing can lead to some side effects:
- Jaw strain: Constant chewing can put strain on the jaw muscles and joints, potentially leading to temporomandibular disorder (TMD).
- Digestive issues: Chewing can cause you to swallow excess air, which may lead to bloating, gas, and abdominal discomfort, especially in people with Irritable Bowel Syndrome (IBS).
- Dental health: While sugar-free gum with xylitol can be beneficial for dental health, gum with sugar can contribute to tooth decay and plaque buildup.
Conclusion
Scientific evidence strongly suggests that chewing can, in fact, make you more alert by increasing cerebral blood flow, stimulating brain activity, and moderating stress. While the effects may be most noticeable in the short term, they represent a simple and accessible method to boost cognitive performance and combat mental fatigue. The effectiveness can depend on factors like the chewing material and context, with some evidence suggesting that chewing harder materials could offer more robust benefits, such as increasing brain antioxidant levels. It's a low-risk intervention that, when used in moderation and with sugar-free options, can be a valuable addition to your arsenal for staying focused and productive. For those seeking a non-pharmacological way to enhance mental clarity during demanding tasks, chewing offers a promising and practical approach.
An extensive review of neuroimaging data provides further support, confirming that chewing engages broad brain circuits related to attention and stress regulation.
