I recall reading about changing modern diets, the effects of chewing and jaw/teeth positioning.
I think it’s important to add that what affects crooked teeth is also tongue placement, effective nasal breathing (not mouth breathing), good upper palate/archway in the mouth for the tongue to rest etc.
Of course the child also needs nutrients to ensure healthy teeth, development, protection. But it’s useful to add in the importance of tongue placement, open airways, nasal breathing to this topic. *Not an expert, just follow a few dentists in this area. Lots of interesting research and findings.
I was always under the impression it was due to tribal peoples needing to chew their food more, since they generally eat less processed food than what western cultures eat. e.g. whole veggies, greens, and meat are more difficult to chew than french fries, ground beef, chicken nuggets, pasta, white rice, wonderbread, cheese, the list goes on. Less demand on the jaw and jaw muscles means less development and more crowded teeth.
This is probably a better explanation than most other commenters are offering up, since it’s less handwaving than “some populations have better oral posture for some reason”, but is still consistent with the fact that facial structure development is known to be dependent on facial muscle use.
I don’t have any studies on hand since I haven’t looked into this for a while, but this should give you a good head start on finding more info if you wish.
I looked into this for a bit and it seems that those who eat softer foods continually throughout their life are more likely to have crooked teeth, not as developed jaws, etc. (Think Western diet, processes foods, etc) While those who eat a variety of foods that are tougher to eat and chew tend to have more developed jaws and thus almost perfectly aligned teeth and healthier teeth. I wish I had known this when I was a kid, I would have totally chew nuts and crunchier foods all day
I had a friend recommend this: Breath: The New Science of a Lost Art by James Nestor I read it skeptically but I very much respect my friend’s wisdom. It’s a fascinating read. It’s all about breathing through your nose. He says that mouth breathing is related to crooked teeth–among many other health issues. Don’t laugh, but he recommends taping your mouth shut at night to sleep better. I did it and it WORKS. You use a small piece of tape that goes across your lips, like this: –\^|\^— vertical line is the tape (lousy ascii drawing).
A few different culprits impact our jaws and teeth:
Just a non-scientific anecdote, I grew up with completely perfect aligned teeth. I also happened to rarely eat with my cutlery as a kid. My parents would always yell at my brother and I to “USE YOUR KNIFE AND FORK!” and we’d use them briefly before going back to fingers. One dentist asked me as a teenager if I had braces, and almost didn’t believe that I’d never had them?!? (I don’t see how she could have been so incredulous though, I thought teeth generally had the square markings left on them after braces, while I had none of that…)
PS- I swear even as an adult, food tastes better when you’re eating with fingers. Tearing that hunk of meat or bread off with your teeth. Mmmmmm. (I only do it at home on occasion 😂)
I thought it was genetic. 🤷🏻♀️My teeth look very similar to my dads. All of mine came in straight except one tooth that was pulled out early (I was 16 and still had a baby tooth) it wasn’t ready to come out so my teeth shifted and the tooth came in behind where it should have been
Not sure about nutrition, but related anecdote, true story…
My son’s teeth were crooked as hell when he was around 10 or 11. Because he’s mildly autistic, we were in no rush to put braces on him because we weren’t sure how he would handle it. Fast-forward about 3 years, we hadn’t really paid attention to his teeth because he seemed to do a good job brushing and never got cavities, I’m talking to a friend about braces and I call my son over to show them how crooked his teeth are, and somehow magically they’d fixed themselves, almost perfect, definitely not needing braces any more. Made me wonder if parents are too quick to put braces on their kids when they’re young.
Diet is critical and does affect the shape and size of jaw. However, this happens over time, A healthy diet won’t fix the size and shape one is born with… the changes happen over time, and are results of what parents, grandparents and their parents ate. Westin Price, DDS studied this all over the world. His book explains it all. It was required reading for my Functional Nutrition program.
Nutrition and Physical Degeneration https://www.amazon.com/dp/0916764206/ref=cm_sw_r_cp_api_glt_i_MWKA8071TSVRNS6YTHA0