Everyone who’s read this blog for some time, delved into the literature on Darwinian medicine, and/or spent some time reading Paleo blogs knows that heart disease, cancer, obesity, type-2 diabetes, osteoporosis, and many other diseases that are highly prevalent in modern societies are rare or nonexistent among hunter-gatherers and traditional people who are largely unaffected by modern habits. However, less attention is often given to disorders that are considered less harmful to one’s health, such as myopia, malocclusion, and crowded teeth. I’ve had to deal with all of these three conditions. I started using contact lenses at a relatively early age, had to pull several teeth to prepare the mouth for orthodontia, and spent years wearing dental braces to correct my malocclusion. Before I started reading up on Paleo and evolutionary medicine, I simply thought that these problems were a “normal” part of human life – after all, so many people seemed to get them – and that I was among the unlucky bunch who were especially afflicted.
I now know better. While genetic susceptibility (including epigenetics) clearly does play a role, environmental causes are also very important. In my recent post titled ‘Organic Beauty‘ I discussed how the Western diet and lifestyle impact the development and growth of the human body. Organic Beauty is a term I coined to describe the physical appearance and characteristics of people who live in environments that closely resemble those hominins evolved in as hunter-gatherers in the Paleolithic era. These people typically have broad dental arches, perfect vision, well-developed faces, low incidence of tooth decay, healthy-looking skin, strong bones, and good posture (1, 2, 3). This is in stark contrast to modern societies, where myopia, narrowed dental arches, malocclusion, tooth decay, acne vulgaris, excessive anterior pelvic tilt, and upper crossed syndrome are extremely common.
I’ve discussed the causes and potential treatment for many of these mismatch conditions before (click links above), but I have yet to write about problems associated with dental health. Why do so many people in modern societies have malocclusion, crowded teeth, and narrowed dental arches? To get the ball rolling on this topic I’m including one of my favorite AHS talks, which is titled “Craniofacial Dystrophy: Modern Melting Faces“. In this presentation, Dr. Mike Mew talks about the impact modern processed diets have on occlusion and teeth alignment.
Quick info about the concept of craniofacial dystrophy:
Thirty percent of the population of most western countries have some form of orthodontic treatment – some with major jaw surgery – for a condition that, based on skeletal records, did not appear until modern times. In some situations, this change has happened in one generation and mirrors many ENT conditions, jaw joint problems, sleep apnoea and snoring, in having a poorly understood aetiology or cure.
The concept of Craniofacial Dystrophy is one that attempts to relate all these issues as a syndrome and suggests that faces have changed shape due to environmental influences and that the functions of the face are affected by these changes. It is suggested that this has been overlooked by specialists working in isolation to each other, avoiding fundamental questions that may bring uncomfortable change to their profession.
The importance of diet and oral posture
In the ancestral health community we tend to place a lot of focus on how the intake of sugar, omega-3, and other micro- and macronutrients has changed over the last several millenia, but we often forget to include the toughness/hardness of the diet, which has changed dramatically since our days as foragers in the Paleolithic era. Even those who consume a Paleo-based diet or eat primarily whole foods use their masticatory system a lot less than hunter-gatherers, who often use their teeth as tools to prepare clothes and eat a high volume of wild meat and fibrous, uncultivated plant food.
Just like excessive sitting and inadequate physical activity can lead to abnormal growth and development of the skeleton, inadequate use of the masticatory system during childhood can cause malocclusion, narrowing of the dental arches, and crowded teeth (1, 4, 5). On the flip side, just like the bones in your arms adapt by growing thicker and stronger if you add plenty of arm exercises into your training program, your jaws will adapt over time if you apply mechanical forces through the chewing of hard, tough food.
Personally, I’ve started to pay a lot more attention to my “oral posture”, trying to keep my teeth together, lips sealed, and tongue at the roof of the mouth, and the hardness of my diet. It’s important to note though that it’s difficult to tell exactly how much of an effect diet and oral posture have in adults, as studies in this area have primarily focused on children. Time spent chewing, infant feeding practises, oral posture, and maternal nutrition can all impact the occlusion, teeth alignment, and dental arch development of a child (1, 4, 5).
I think this is a very interesting and important topic, which I’m likely to explore further in future blog posts… If you have any thoughts, comments, or links to good research then feel free to post them in the comment section!