Chewing. We do it hundreds of times daily. The act of chewing is vital to our health and wellbeing, and not just for nutritional sustenance. Yet, do we, as dental health professionals ever talk with our patients about their ability to chew properly or look beyond the teeth and gums to evaluate their chewing abilities? So many of our patients have “digestive issues”, malocclusion, shrinking too small faces, sleep breathing disorders, and temporomandibular dysfunction and pain.
Could it be related to improper chewing and swallowing? The simple act of chewing has many consequences. I wrote about chewing long ago and felt it time to add more important information. Join me and learn more about the proper chew: part two!
History First- The Master Chewers
The human face is indeed changing. It is shrinking faster than evolution would dictate. Malocclusion is at epidemic levels. Yet, if we look to history, we would see prehistoric man had little to no dental diseases, and 32 healthy straight teeth in a nice wide arch. No hygienist pestered him to brush or floss. Man spent hours each day chewing hard foods, nuts, and seeds. All that chewing was the key to prehistoric man’s health. The constant action of chewing grew the airway, made the bones of the face and jaws pronounced, and kept the teeth clean and healthy.
Around 12,000 years ago things began changing. Man went for hunter/gatherer to farmer. He started cooking. This led to eating different, softer foods. He was able to eat more calories more quickly and did not need to eat all day. Fast forward to the 1700’s up to today with even more milling of wheat and rice, meats, fruits and vegetables that were canned and bottled. Sugar joined the food lineup. Food is now devoid of nutrients, fiber, minerals, and vitamins. It is soft, mushy, and easy to swallow. We have an epidemic of dental diseases, malocclusion, and a shrinking, stunted human face. Breathing and airway issues have surged. Obesity became common. Smoothies and Dino nuggets replaced real food. We no longer need to chew.
What Happened to Chewing?
With the turn of the 20th century, breastfeeding declined, pureed baby food became the norm, and fast food took over. Processed foods are the reason so many of us have stuffed noses, clogged airways, and snore. This soft diet directly influences how our face and jaws grow.
Bottles, pacifiers, and sippy cups are also to blame. They teach infants and toddlers to keep their tongues in a low improper resting position either in-between the teeth or resting on the floor of the mouth. The tongue is a powerful muscular hydrostat that can alter the alignment of the teeth.
An improper rest position pushes the tongue against teeth. The forces of the tongue in this improper position created a forward tongue swallow which creates abnormal forces on the teeth and bones, which alter the shape of the teeth and arches. Permanently. Resulting in malocclusion. Muscle trumps bone.
Why Chewing Matters
Saliva production is vital to a healthy mouth and strong healthy teeth. Chewing stimulates saliva production and so much more. We need a good flow of saliva to control the oral pH, remineralize teeth with nutrients within the saliva, wash the teeth, buffers the acids we eat and drink, and removes food and bacteria. I think of saliva as liquid gold for the mouth. It contains enzymes like:
Lactoferrin- a protein that steals nutrients from bacteria as a way of starving them
Lysozyme: defends you from the bacteria by breaking down their cell wall
Lactoperoxidase: which is antibacterial, antifungal, antiviral, and antiparasitic. Perfect to protect us from tooth decay and gum diseases.
It also contains Proline-rich glycoproteins that help anchor good bacteria to our teeth as well as immune system proteins that bind and eliminate pathogens and keep the mouth clean. Without good salivary flow our teeth would crumble and succumb to tooth decay. Dry mouth sufferers will tell you it is a very uncomfortable situation to be in. Chewing does help stimulate salivary flow.
Chewing also stimulates the taste receptors in your mouth which then triggers the gastrointestinal system. The digestive process has begun. This tells the stomach to start producing digestive acids and signals the pancreas to begin producing enzymes that are passed to the small intestine to aid digestion. Saliva relaxes the pylorus, which allows the food to travel out the stomach and to the small intestine. By bypassing the chewing motion, we do not produce enough saliva to start the digestive process. Digestive “issues” can result. 
We need all our forces inline to properly influence breathing, tongue position and mouth muscles. Nasal breathing develops the jaws and creates straight teeth. Chewing strengthens the jawbone, which is vital for our periodontally involved patients, and provides architecture for the airway. The more we chew, the more stem cells are released.
The temporomandibular jaw joint also requires stimulation to develop properly and stay strong. Muscles, bone, and joints of the face need to support the airway. Exercising the TM joint is key to keeping the airway healthy. Chewing is that exercise.
The shape of the face is tightly connected to development of the muscles that let us breathe, chew and swallow. It is vital to develop the jaw properly in a natural way.
The tongue plays a key role in this development. By resting on the palate, it exerts 700 grams of pressure outward which stimulates it to expand and grow. The masseter (cheek muscles) exerts 500 grams of pressure inward which counterbalances the tongue. Should the tongue not be resting on the palate, the forces of the masseter drive the maxilla (the upper jaw) inward and cause a high vaulted palate, narrow, “V” shaped arches and small, crowded teeth and jaws. The underdevelopment of the maxilla then restricts the growth of the mandible (it locks it in like a too big foot stuck in a too small shoe).
The Proper Chew and Swallow
The tongue has a proper resting position on the roof of the mouth, with the tip resting right on the incisive foramen. It should go no farther forward than its “spot” during drinking or chewing. As you chew food the tongue pushes against the upper molars, moving the food to be crushed by the molars. A rule of thumb is chew at least 20 times before swallowing. Food should be soupy. Then the tongue starts gathering the now “bolus” of food saturated with saliva. The middle (or body) of the tongue continues to rise up to the roof of the mouth. Just like a wave, the very back of the tongue rises up, swishing the food/drink down the esophagus.
Chew Your Way to a Bigger Mouth- Especially for Children
The hard palate has a mid-palatine suture. Growth occurs at suture lines- inside sutures have stem cells that can become bone or tissues as the body needs. Stem cells are mortar that binds the sutures together and grow new bone in the face and mouth. Maxilla can grow more dense and remodel at any age. (Even in adults!) Bone growth can occur by engaging the masseter over and over. Chewing more releases more stem cells.
The tongue belongs on the roof of the mouth when not eating, talking or otherwise communicating. Proper tongue rest posture puts pressure on the maxilla to expand and grow around the tongue. Nasal breathing creates a flow of air through the nose which stimulates the maxilla to keep growing outward and helps to lower and broaden the palate. Nasal breathing is healthy breathing.
Chewing for the Health of It
In addition to developing the face for airway health, and prevention of sleep breathing disorders chewing is also vital for brain function and cognition, gastric motility and blood flow.
Brain function and cognition – chewing improves cognitive brain function and relieves stress.
Chewing reduces stress and anxiety-like behaviors.
Gum chewing during stress may affect the levels of various stress markers in the saliva and plasma and increase attention, self-rated alertness, and vigilance.
Chewing and Dementia:
Tooth loss is an epidemiologic risk factor for Alzheimer’s disease. Abnormal mastication due to tooth loss or occlusal disharmony induces chronic stress, leading to pathologic changes in the hippocampus and deficits in learning and memory.
Chewing and gastric motility:
in patients unable to chew, a lack of chewing reduced the autonomic nervous activity resulting in adverse effects on the gastric motor function and excretion function. 
Chewing and cerebral blood flow:
is influenced by the contraction of the masseter muscles during clenching and chewing.
Bottom line- chew it or lose it!
Infants: Breastfeeding shapes the airway and palate. It teaches the tongue to rest on the palate. Breastfeeding stimulates stem cell growth for stronger bones and thus better airway development. Tongue and lip ties can hinder the ability to breastfeed and advance to solids or learn to eat a variety of food.
Babies, Toddlers and Children: Watch for choking hazards- small round objects like hot dogs, marshmallows, and grapes should be cut smaller to prevent choking. Sixty-six to 77 children die each year from choking.
Eliminate sippy cups and bottles as they further train the tongue to remain on the floor of the mouth.
Picky eaters: Mouth breathing, and allergies can result in enlarged palatine tonsils which can cause children to gag more easily and have difficulty swallowing certain foods. Gagging is uncomfortable so children will avoid foods that trigger it.
Misaligned and maloccluded teeth can cause a child to prefer certain foods that are more comfortable and easier to chew and swallow. An anterior open bite due to thumb or pacifier sucking may make it difficult to propel certain foods backward due to an immature swallow. In order for a child with an open bite to swallow, he must place his tongue between the lips to create a seal to create low pressure within the mouth in order to achieve a swallow. A tongue thrust /forward swallow may indicate weak masseter muscles.
Tethered oral tissues: Both tongue ties and buccal ties can restrict lip, jaw and tongue movements and growth. Tongue ties prevent lateralization of tongue. (Tongue lateralization is vital in order to manipulate food and form a bolus before swallowing.)
Teens: distracted eating, poor diet choices and constant snacking, and energy drinks.
Malocclusion – cannot chew food properly and have trouble breaking down food so eat soft diet, mushy foods. A tongue that is “tied” cannot more and manipulate food and thus these folks prefer soft, easy to swallow mushy foods (like carbohydrates and soft proteins).
Adults: – not chewing food thoroughly enough. Belching/aerophagia- swallowing air due to improper swallowing/breathing.
Improper chewing leaves food residue and plaque on the unused side. Chewing and salivary production keep the mouth cleaner, with less plaque and debris.
Seniors: Dentures and choking are a concern because the denture patient may not be grinding the food properly. Dentures make is difficult to sense whether food is fully chewed before swallowing. A poorly fitting denture may also cause the person not to wear it to eat, or they may not be able to eat with them at all. Death from choking by those over 74 years of age affects approximately 2,800 people yearly.
Xerostomia in adults and seniors also affects chewing and swallowing abilities. 
Signs of Poor Chewing:
Open mouth chewing
Inefficient breakdown of food
Poor salivary production
Food stuck to teeth
Small bites- only what fits on fork comfortably- not falling off fork.
Cut meat into small pieces.
Feet on the floor – stabilizes core and allows good posture, concentrate on fine motor skills **Especially important for infants and small children whose feet have nothing to rest on while they eat.
Use lips to remove food from fork.
Divide food in half and chew evenly on both sides.
Chew thoroughly- soak the food in saliva.
Put things such as nuts in smoothies to encourage chewing.
Avoid speaking or laughing with food in the mouth.
Chew These Foods
Chewing is the best preventive medicine to grow a healthy mouth and airway, and to have naturally straight teeth.
Chew hard foods such as:
nuts, seeds, raw vegetables, meat on the bone, and dried and cured meats,
carrots, celery, seeds, raw foods, tough foods, apples with peel
Chewing – The Final Swallow
As dental health professionals, we must look not only at teeth and gums but the entire person. They trust us to educate them and look out for their best interest. Helping them grow, breathe, chew, swallow and sleep better are all things within our dental scope of practice. Discussing how well they can chew their food should be a conversation we have with each and every one of our patients. With the epidemic of shrinking jaws, malocclusion, tooth decay, chronic diseases, and breathing disordered sleep we must look deeper and start at the beginning- how we chew our food. Our immune system will benefit. Maybe it really is that simple.
Bet you had no idea how important the simple act of chewing really is to our health and development. Enjoy your next meal by chewing it mindfully.
Thanks for reading and keep smiling!
Yours in health,