https://stanfordpress.typepad.com/blog/2018/05/why-cavemen-needed-no-braces.html, posted 2 Mar by peter in food health science
At its root, the problem we face is that we have entered a space age world with Stone Age genes – genes that evolved to produce jaws adapted to a hunter-gatherer diet. Today's jaws epidemic is concealed behind the commonplace. Its most obvious symptoms are oral and facial: crooked teeth (and the accompanying very common use of braces), receding jaws, a smile that shows lots of gums, mouth breathing, and interrupted breathing during sleep. A bother, but hardly an 'epidemic' – at least until one recognizes the relationship between malocclusion and a veritable host of downstream health consequences.