Defending a Brain Declining from Smartphone Addiction with 'Chewing Power': The Enhancement Mechanism of 'Cognitive Reserve' Generated by Chewing

Modern people are constantly overworking their brain’s processing capacity (working memory) to its limit due to the endless wave of smartphone notifications and SNS timelines. When aging is added to this “digital fatigue,” it triggers forgetfulness and a dramatic decline in concentration (brain fog).

As a concept to combat such brain decline, “Cognitive Reserve” is attracting attention in the field of neuroscience. This is, so to speak, the “brain’s reserve tank,” and the larger this tank capacity is, the longer a person can maintain normal cognitive function even if damage accumulates in the brain. Amazingly, one of the most efficient ways to expand this reserve tank on a daily basis and for free is “chewing (mastication).”

Chewing Maximizes “Blood Flow” to the Hippocampus and Prefrontal Cortex

The act of chewing is not just moving the jaw muscles. From the brain’s perspective, it is equivalent to operating a “powerful blood pump” to the entire head.

• Dramatic Increase in Cerebral Blood Flow: When the chewing motion begins, strong electrical signals are sent from the facial trigeminal nerve to the brainstem, instantly making the blood flow throughout the brain jump (such as fMRI studies related to E01). In particular, it has been confirmed that the supply of oxygen and glucose to the “hippocampus,” which governs memory, and the “prefrontal cortex,” which is responsible for advanced judgment and concentration, significantly increases.
• By repeating this “blood flow boost” at every meal three times a day, the maintenance and strengthening of the brain’s neural network (synapses) are promoted, and the “dam” named cognitive reserve becomes slightly larger and stronger.

The “Serotonin Buffer” That Protects the Brain from Chronic Stress

Furthermore, chewing goes beyond physically increasing blood flow and rewrites the balance of neurotransmitters in the brain to a “brain protection mode.”

• Modern digital stress and overwork cause the stress hormone (cortisol) to be chronically over-secreted in the brain, and if this continues for a long period, the nerve cells in the hippocampus will physically atrophy (be destroyed) (the model of stress and brain atrophy related to E10).
• However, if you “continue to chew at a constant rhythm (rhythmic movement)” gum or the like, “serotonin (the hormone of relief and stability)” is secreted from the raphe nucleus of the brainstem (related to E11). This serotonin acts as a “barrier (buffer)” to protect the hippocampus from the toxicity of excessive cortisol, preventing brain atrophy (decline in cognitive function) caused by stress beforehand.

Practical Lifestyle to “Protect the Brain by Chewing”

To expand the brain’s reserve tank (cognitive reserve) and combat aging and stress, a strategy is needed to intentionally maintain and strengthen “chewing power” in daily life.

• Breaking Away from Modern Meals That Have Become “Liquid Foods”: “Meals that can be swallowed without chewing,” such as soft bread, hamburgers, and smoothies, remarkably lower the pump utilization rate to the brain. Strategically introduce “ingredients with high resistance to the jaw” such as brown rice, nuts, and root vegetables to routinely generate blood flow spikes to the brain.
• “Strategic Chewing” During Work: Start chewing hard gum at the timing when you are intensely concentrated on computer work and your brain begins to feel fatigued (when cognitive load is high). This physically raises the blood flow to the prefrontal cortex that was about to decline, and at the same time, makes it possible to calm the disturbance of the autonomic nervous system caused by stress with serotonin.

The act of “chewing” is not merely the first step of digestive activity. It is the most accessible and powerful “brain anti-aging device” that we can control ourselves.