Chewing Gum affects Mood & Cognition in surprising ways!

Many research studies show chewing gum can improve attention, concentration, alertness, test performance, and mood. It can even prevent or extinguish a song stuck in your head. However, chewing gum might not improve memory per se. Let’s see what the evidence suggests.

Clarification: Mood is a stable feeling like being calm, relaxed, stressed, anxious, etc., and Cognition is mental processing including memory, attention, and thought process.

Can make you more alert

The hype of chewing gum is real when it comes to improving alertness and concentration. Research suggests^[1] that chewing gum can make you about 10% more alert and also improve your performance on intelligence tests. Chewing gum also tends to improve reaction time and attention. A study^[2] on 133 volunteers showed chewing helps improve many aspects of brain function including improved mood, selective and sustained attention, and increased alertness. Researchers identified an improvement in alertness by measuring heart rate and cortisol levels, which are similarly higher when a person is alert after experiencing moderate stress. The underlying mechanisms are unclear but research has found nuances to this effect. Chewing gum is likely to broaden attention and then improvements in attention come after^[3] a person has spent time on a task. Extending this finding to daily life, the study suggests that if boredom is reducing attention, chewing gum can counter it to some degree.

Gum’s boosting effect on attention doesn’t depend on attention gradually dropping as one does a task. This means chewing gum enhances baseline attention. And current evidence does not show support for the idea that chewing gum can take attention away from a task through multi-tasking. You can freely use gum to improve your attention without worrying if it distracts you, at least the studies suggest this. Multi-tasking isn’t generally bad because other studies have repeatedly shown that multi-tasking improves performance on boring tasks by preventing mind-wandering and increasing engagement with the work.

The act of chewing, called mastication, is well-studied^[4] and there are 2 tendencies according to a meta-analysis:

1. Attention and alertness improve via the act of chewing
2. Feelings of losing focus (drowsiness, fatigue, etc.) due to cognitively demanding tasks reduce

Can stop an earworm

If a song is stuck in your head, chewing gum is an experimentally verified way to stop the earworm. Chewing gum engages the Articulatory Motor Programming network^[5]. The AMP is responsible for pushing abstract auditory representations into awareness by initiating the sounds and processes that you eventually hear in your head. When you distract it via chewing it reduces the likelihood of actually hearing the music in your head. Chewing interferes with the AMP that is recruited for an earworm by re-recruiting it for the act of chewing. It also stops the brain from recruiting the AMP in the immediate future, so new tunes won’t pop out. Essentially AMPs limited resources are diverted to chewing and they prevent a song from even entering your awareness because the song needs the AMP.

Caffeinated chewing gum’s double benefit

Chewing gum with no real “active ingredient” works – so basically any chewing gum you like is good enough. Essentially, the action of chewing gum and a baseline increase in brain multi-tasking with gum improves mood and alertness. But some varieties have caffeine in them and they can have an additive effect, the same way some medication contains caffeine in them.

Caffeinated gums^[6] improve mood and alertness through the action of caffeine. Caffeine improves overall arousal, concentration (sustained attention while working), and encoding of new information (learning something new and converting it into memory). This comes from higher body arousal that evolved to help us adapt quicker and faster, and make quick decisions like in a fight or flight situation.

One possible mechanism^[7] for this is that caffeine in the gum binds to adenosine receptors in the brain. These receptors slow down neural signaling which we interpret as sleepiness. Adenosine is a neurochemical made by the brain that binds to adenosine receptors as a part of normal brain functioning. But caffeine looks the same to other nerves because caffeine and adenosine are structurally similar chemicals. So when caffeine, instead of adenosine, binds to the receptors, there is no adenosine action leading to drowsiness. Instead, there is a caffeine action that increases arousal and nullifies ongoing drowsiness. Caffeine blocks out adenosine, and instead of adenosine slowing neural signaling, caffeine speeds it up. Caffeine then tightens blood vessels in place of adenosine which would’ve opened them up. The pituitary gland uses this change in the brain as a signal to push adrenaline into the system, making us more alert and energized as seen during a fight or flight response.

So if for some reason, you do not want to continue having too much coffee or decaf isn’t an option, you can use caffeinated gums to balance your coffee intake. You can have the benefit of gum and caffeine simultaneously.

Similarly, moderate stress, which arouses the body, improves (not worsens) memory and cognitive functioning to adapt faster. Too little arousal or extreme stress works the opposite – it impairs brain function.

Unclear effects on memory

Studies have found no direct improvement in memory^[8] or recall through chewing gum and some have even observed that memory worsens. Specifically, chewing gum worsens short-term memory^[9] for remembering sequences like letters, words, and ordered items. One explanation is that chewing gum occupies the brain’s vocal-articulatory planning system which is needed for recalling ordered information. Another study^[10] suggests that chewing impairs verbal memory because it worsens word encoding during initial learning. Word encoding is how we learn new words and assign them meaning for the brain to process them better. It is a neural mechanism. Chewing might take resources away from word encoding because word encoding requires using silent inner speech and micro-signaling to oral muscles for better encoding. Chewing essentially hijacks inner speech and micro-signaling through the chewing motion.

So while you might be able to concentrate better on a task you are good at while chewing gum, you might worsen your memory for a new list of priorities you get at work or hear in a meeting.

Some researchers say that chewing gum can improve memory, and as of today, the results are mixed. One speculative explanation^[11] for memory improvement is that chewing mobilizes glucose and that brain uses that for deeper processing of learned information. Chewing creates the action of eating without food, so the brain interprets this as a signal to release stored glucose. Another mechanism is that chewing triggers an eating impulse that puts the body in a “rest & digest state” governed by the parasympathetic nervous system, instead of the “fight or flight” system governed by the sympathetic nervous system. When in rest & digest mode, we are relaxed, muscles are less tense, and the body is in homeostasis – it is a feeling of safety, as opposed to “fight or flight”, which is a threat. So if chewing triggers it, we trick the brain into feeling relaxed.

One form of memory called context-dependent memory may^[12] or may not^[13] improve with chewing because study results are highly mixed. Context-dependent memory means you can remember something better if you are in a context similar to the context when you first learned it. So if you chewed gum while memorizing 10 different varieties of plants, it’ll be easier to recall them when you are chewing than when you are not. This generally has a practical anecdotal example: Students who learn while gumming perform better on tests when they are gumming. One reason why context-depend effects are not seen in many studies is that they all used word lists to test recall, which is inherently impaired by chewing. Whether it can improve numerical or spatial information remains unclear.

Can manage stress and anxiety

One study^[14] suggests chewing gum can reduce temporary anxiety caused by social stress, like a job interview. While chewing generally improves mood, the study did not find an increase in calmness, but it did observe lesser anxiety.

Another study^[15] on 492 people that looked at the effect of chewing gum and stress suggests chewing gum reduces everyday stress and abstaining from the habit increases anxiety and feelings like tensing up or being unrelaxed. The study compared those who had a habit of regularly chewing and those who rarely chewed. The findings were similar in both groups. Those who experienced extreme stress did not get the same relief from chewing as those who experienced moderate stress. Generally, chewing gum instantly relaxed them. So, chewing gum is an effective, low-cost, low-consequence coping mechanism for everyday stress.

One study^[16] looked at multi-tasking-related stress and how chewing gum affects alertness, anxiety, and stress. Researchers saw that multi-tasking effectively caused stress and chewing gum reduced that stress as measured by cortisol in the saliva. In a broader context, high cortisol indicates high stress, and low cortisol indicates low stress. The drop in cortisol (the stress hormone) also reduced anxiety and improved attention while multi-tasking. While this was a laboratory study and not a survey of everyday habits, it is directly representing the modern-work environment where people have to multi-task and regularly lose focus and deal with high work stress. Chewing gum can be a quick fix for this multi-tasking-based work stress and drop in focus.

Chewing efficiency (masticatory performance) has an effect on how much stress reduces. A study^[17] suggests that effective chewing, which generally means the flavors are absorbed, the color of the gum is lost, the gum is fully chewed with lots of rotations and gum folding, etc., reduces stress more than ineffective chewing. While mastication is a mundane activity, it can be an effortful activity that mildly occupies attention to chew better, and that might improve mood more. Effortful chewing can keep things more fun and interesting, which counters stress.

Another useful benefit of chewing gum is that it could be an effective addition to medication in treating depression. Chewing can reduce gastrointestinal symptoms like lack of appetite and flatulence which are common in depression. The study reports^[18] those who had gum + medication responded better to treatment than those who had just medication.

Tying this all up

One 2019 study^[19] looked at stress, anxiety, academic performance, memory, exam performance, and attention in a group of 100 students over 19 days and 7 days. They propose that chewing gum improves focus by reducing stress and anxiety. So students can chew gum to improve their exam performance by reducing exam stress. Their study says chewing gum reduces depression, anxiety, and stress effectively, and this mechanism can give cognitive benefits like better exam performance and memory. Those who chewed for more days had better outcomes, but the research literature is still young to declare the long-term benefits or problems of this habit.

Takeaway

Chewing gum is a great way to improve focus and alertness. It can also reduce stress and improve mood. Here are some ways in which you can use gum effectively:

1. You can chew gum to improve your focus and reaction time at work or while studying or during tests.
2. Avoid using gum when your work requires learning many names and words because studies indicate verbal memory will worsen.
3. You can use gum to lower everyday stress like a high domestic workload and even temporary stress like a job interview.
4. If a song is stuck in your head, chew gum.
5. Use caffeinated chewing gums for the bonus cognitive boost of caffeine.

P.S. Photo credit: Photo by Karley Saagi: https://www.pexels.com/photo/woman-in-pink-cardigan-blowing-bubble-gum-5388003/

Sources