Everybody Eats: my suggested title for the prequel of the bestselling children’s book Everybody Poops. While it may not have the excitement and allure of a fascinating tale of elimination, it would be an equally compelling story of the process of digestion. We rarely pause to consider the functions of the organs that process and assimilate our food into our bodies. Yet without our digestive system, our bodies would lack the essential nutrients to keep our beings healthy and vibrant. In this multi-part series, we will explore how our habitual body positioning can throw our digestive systems out of whack.
First, an introduction to your digestive system. Your alimentary canal is a single tube, compartmentalized by function, from your mouth to your anus, with sphincters that pace movement and auxiliary organs that provide juices and enzymes to breakdown food. Its smooth muscle functions outside of your conscious control. Food moves through the tract via peristalsis, or wave-like contractions; like pushing toothpaste out of the tube from the bottom. Skeletal muscles help with voluntary propulsions of food in the throat (swallowing) and rectum (defecation).
Structural imbalances of the muscles that aid in chewing and swallowing can botch proper digestion from the first bite. In part one and two of this series, we will explore the muscles of the jaw and neck that govern chewing and swallowing, what can go awry, and how it can be corrected. Let’s break down chewing.
How often do you consider the strength of your jaw muscles? It’s likely that you only notice your jaw muscles after hours of chewing gum on an airplane only to wake up the next day without being able to open your mouth. Or if you’ve ever experienced teeth grinding leading to headaches or temporomandibular joint (TMJ) disorders.
The muscles that depress, or open, the jaw are the geniohyoid, mylohyoid, and stylohyoid, collectively know as the suprahyoids. You will learn more about this group of muscles in Part Two: Swallowing. The prime movers of jaw elevation, or closure, are the masseter and temporalis. Together, with the suprahyoids, their actions create chewing. We’ll start with the muscles that close and clench the jaw.
The masseter muscle is the strongest muscle in the body relative to its size. It’s the primary muscle used for chewing. The combined power of the masseters is up to 150 lbs of biting force – or enough to bite off a finger. They are located on the sides of the mandible (jaw) between the zygomatic arches (cheekbones) and the sloping curves of the jaw just below the ears.
The temporalis lies at the temples on either side of the head. It sweeps over the fossa, or depression, of the temporal bone and tunnels under the zygomatic arch to connect to the mandible at it’s coronoid process. To find your coronoid process, slide your fingers roughly halfway between your cheekbones and earlobes and open your jaw. The place where your jaw hinges is where the temporalis attaches.
Our jaw and surrounding muscles are designed to tear and gnaw through uncooked plant fibers and meat. When our ancestors began cooking their food, it was the first time food material became tenderized and easy to chew through. Cooking over a fire was the first form of food processing. It changed food from its natural state to something easier for us to masticate. Over the years, we have developed several methods of food production that render our foods almost pre-digested. Nowadays, whole foods are broken down into food components and reformed into convenient caloric packages. However, food processing development has happened faster than human jaw evolution, which has led to misuse of our masseter and temporalis muscles.
Chewing dense food at every meal should fatigue the muscles, however, food processing has superseded our natural food grinding ability. The muscles are left with the desire to chew, suck, or crunch. This craving coupled with persistent stress, has created an environment for habitual jaw clenching, resulting in perpetually contracted masseter and temporalis muscles.
Tight chewing muscles are the ultimate effect, but the causes are not linear. Food manufacturing has made eating more convenient so we spend greater time working, yet the stress of working contributes to jaw overuse. Our jaw muscles are too tired from clenching so we reach for softer, more mashed foods. And because we are not chewing to fatigue the muscles they are more likely to clamp down in the presence of stress. And so on, and so on…
Luckily, there is a way to break this cycle. Eat foods that you have to chew many times before swallowing. Crush your food into liquid before sending it to the stomach. Eat mindfully. Enjoy the flavors and textures of your food. In addition to adequately working your jaw muscles, this may increase the feelings of enjoyment and satisfaction. The nerves that feed into the muscles in the jaw connect to satiety areas in the brain – the higher amount of chewing the more satisfaction you will feel.
For even more satisfaction, encourage your jaw muscles to relax between chewing sessions by rolling the original Yoga Tune Up® Therapy Balls over your masseter and temporalis muscles. The sequences Jaw Joint and Temple Tamer in the The Roll Model will help you unwind your grind.
Chew on this for a while, then come back Friday to learn how to smooth out your swallowing reflex.