By Sharon Bachman
Smoothies are great, but consider this before drinking your calories:
Chewing, or mastication, is more important to our well-being than just crushing food to aid in swallowing and digestion. I’m not in any way trying to down play the importance of chewing on our digestion process, but what I am trying to do is prove the link between chewing and our brain chemistry, and the importance of balanced and proper chewing on neurons in the brain.
In the research article Chewing Prevents Stress-induced Hippocampal LTD Formation and Anxiety-related Behaviors: A Possible Role of the Dopaminergic System, Ono, Koizumi and Onozuka (2015), examined the effects of chewing on stress-induced long-term depression (LTD), concentration, and anxiety behaviors. The study used electrophysiological and micro-dialysis methods of testing rats and found rats that chewed on a wooden stick during restraint induced stress, had elevated levels of dopamine, serotonin, and norepinephrine (all feel good hormones) in the hippocampus region of the brain via it’s reciprocal connection with the amygdala and the prefrontal cortex. The prefrontal cortex plays an important role in regulating anxiety-related behaviors, LTD, and memory. Another study conducted by the University of Cardiff found that people who tend to chew more often report lower levels of anxiety, stress and depression. These researchers believe that chewing activates a pattern of serotonin (a feel good hormone) in the brain.
In another article entitled, Chewing and Attention: A Positive Effect on Sustained Attention, Hirano & Onozuka, (2015), have discovered a relationship between chewing and cognition, especially attention. Chewing gum aids in sleepiness prevention during learning, work, and driving. The findings of this study found a unique function that affects brain function. These functions were investigated by means of electroencephalography (EEG). Obviously, there’s an explanation involving the neurophysiological aspect: researchers found that when chewing, not only the attention increases, but also the cognitive processing speeds up. In reality, when chewing, we concentrate better and are more careful, so that we respond more quickly to stimuli.
Scientists believe this is a primal heritage. Generally, when animals eat they are more helpless. It is logical that in this moment they need to have increased senses to detect and react to possible dangers.
Eat lots fresh, raw, and crunchy fruit and vegetable snacks which require a great deal of chewing. Recite the alphabet while you chew each mouthful. This will ensure time for our brain to send “full” signals, help release all those feel-good brain hormones, which combat long-term depression (known to cause us to over eat), help with anxiety behaviors (also known to cause mindless eating), increase memory, attention, and relaxation. It takes 20 minutes for our brain to tell us we are full. Chew slow, enjoy the taste, and texture of each morsel to give your brain time to feel full. Chew zero calorie gum during stressful times.
In a study by the Massachusetts Institute of Technology, found that chewing activates the production of a brain-produced neurotrophic factor, which acts as a nerve growth factor, as well as the neurotrophin-3, a protein growth factor that helps existing neurons to survive and differentiate, as well as enhances the growth and differentiation of new neurons and synapses. However, this occurs only when the trigeminal nerve is activated in a symmetrical manner. In other words, proper bite and symmetrical chewing is also very important.
Researchers believe that the mandibular asymmetry or uneven chewing, causes problems at cognitive level because it alters the functioning of facial muscles and nerves. These, in turn, are connected to the brain, so the chewing process is encoded in a different way and the brain assumes that it is not necessary to activate many neurons since muscles do not work as before. This causes cognitive impairment.
People with dental problems and uneven bites, can cause less nerve/brain interaction which causes a decreased activity in certain brain areas. In fact, studies revealed that a severe tooth loss before age 35 is an important risk factor in the development of dementia or Alzheimer’s disease and neurodegeneration which also affects the formation of new memories.
A relatively newly studied area of the brain is the dentate gyrus which can generate and regenerate neurons. This area of the brain is in charge of storing and retrieving memories, which is why there may be a link between chewing and some forms of dementia.
The longer and more proper we chew our food, the more we make it our own. In saying this I mean, the longer we chew, the more our food is mixed with our own saliva, which makes it easier for us to digest. In mixing with our own saliva we have customized the food to fit our system.
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Hirano, Y., Onozuka, M. (2015), Chewing and Attention: A Positive Effect on Sustained Attention. Biomed Research International. Volume 2015, Article ID 367026. doi.org/10.1155/2015/367026
Okamoto, O. et. Al. (2010) Relationship of tooth loss to mild memory impairment and cognitive impairment: findings from the fujiwara-kyo study. Behavioral and Brain Functions; 6:77.
Ono, Y., Koizumi, S., & Onozuka, M., (2015). Chewing Prevents Stress-Induced Hippocampal LTD Formation and Anxiety-Related Behaviors: A Possible Role of the Dopaminergic System. BioMed Research International. Volume 2015, Article ID 294068. doi.org/10.1155/2015/29408
Onozuka, M. et. Al. (2000) Impairment of spatial memory and changes in astroglial responsiveness following loss of molar teeth in aged SAMP8 mice. Behav Brain Res; 108(2): 145-155.
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