Americans' heads have been growing, scientists say
June 5th, 2012
02:43 PM ET

Americans' heads have been growing, scientists say

If you're American with an average-sized head, your noggin is likely bigger than your ancestor's was seven generations ago.

That's the implication of research by Richard Jantz and colleagues at the Forensic Anthropology Center at the University of Tennessee.

The scientists analyzed about 1,500 skulls, dated from various years in the 1800s and 1900s. The researchers focused on Caucasian individuals because there weren't as many skulls from blacks and Hispanics. Although their conclusions are about white Americans, there is no reason to believe these patterns don't pertain to other races, Jantz said. More research just needs to be done.

Over the last 150 years or so, it appears that skulls got narrower from side to side by about 5 to 7 millimeters, and higher from top to bottom by an average of nearly 10 millimeters, Jantz said. And the overall size of the head has, on average, increased by an amount equivalent to the size of a tennis ball, he said.

Jantz speculates that there are several factors in the American environment that help contribute to this trend:

For one, there is far more nutrition than ever before in the United States. The problem of obesity - of over-nutrition - is more of a concern than undernourishment. People's work has become less physically-intensive, and even manual labor is often assisted by machines in some way.

Because of cars, people walk less. Because of vaccines, epidemic diseases that once killed many children no longer do.

Mothers who might not have survived childbirth two centuries ago are now living, thanks to medicines and procedures such as Caesarean sections - their children are surviving, too. And people don't often choose mates with the very same ethnicity – particularly not from the same part of Europe as their own ancestors – as they would have before.

"That has resulted in opening up the gene pool," Jantz said.

Brain size is probably correlated with skull size, so this means Americans' brains may also be getting bigger, but this has yet to be proven. The next step for researchers would be to see if certain parts of the brain have expanded, which might give an indication of whether there are particular abilities that have been enhanced as a result of this change over time.

The researchers did not directly measure the circumference of the head, so it's hard to say whether this trend has had any effect on hat size.

Is the increase in skull size part of a larger pattern of the human body growing in general? It's true that people are on average taller today than in the 1800s, but height has plateaued. What about our heads?

"I think the skulls will continue to change, and I think the direction depends on the direction the environment goes," Jantz said. "Obviously there have to be limits on how narrow or on how tall it could get, so I don't know if I want to predict how much longer this trend will continue."

The researchers hope to get this research published. They presented their findings at the American Association of Physical Anthropologists meeting in April.

soundoff (856 Responses)
  1. Camper Repairs Near Me


    June 15, 2021 at 00:28 | Report abuse | Reply
  2. Nearest RV Repair


    June 15, 2021 at 01:53 | Report abuse | Reply
  3. RV Repair Shops Near Me Now


    June 15, 2021 at 01:59 | Report abuse | Reply
  4. RV Repair Santa Ana


    June 15, 2021 at 02:29 | Report abuse | Reply
  5. Sprinter Repair Shops Near Me

    Oh my goodness! Awesome article dude! Thank you so much, However I am having problems with your RSS. I donít understand why I cannot subscribe to it. Is there anybody having identical RSS problems? Anyone that knows the answer will you kindly respond? Thanks!!


    June 15, 2021 at 03:34 | Report abuse | Reply
  6. Tabatha Kiddy

    Have you ever heard of second life (sl for short). It is essentially a online game where you can do anything you want. sl is literally my second life (pun intended lol). If you want to see more you can see these sl articles and blogs


    June 15, 2021 at 06:30 | Report abuse | Reply
  7. Thad Bun

    Have you ever heard of second life (sl for short). It is basically a online game where you can do anything you want. Second life is literally my second life (pun intended lol). If you would like to see more you can see these Second Life websites and blogs


    June 15, 2021 at 08:44 | Report abuse | Reply
  8. RV Repair Shops Nearby

    After I originally left a comment I appear to have clicked the -Notify me when new comments are added- checkbox and now whenever a comment is added I get four emails with the exact same comment. Perhaps there is a means you are able to remove me from that service? Many thanks!


    June 15, 2021 at 11:49 | Report abuse | Reply
  9. Sprinter Repair Shop Near Me

    A motivating discussion is worth comment. I do think that you should publish more about this subject matter, it might not be a taboo matter but typically folks don't discuss these issues. To the next! All the best!!


    June 15, 2021 at 13:49 | Report abuse | Reply
  10. Sprinter Repair Shops Near Me

    Hi there! This post couldnít be written any better! Going through this post reminds me of my previous roommate! He continually kept talking about this. I'll forward this post to him. Fairly certain he'll have a good read. I appreciate you for sharing!


    June 15, 2021 at 13:50 | Report abuse | Reply
  11. RV Repair Near Me Now

    An intriguing discussion is worth comment. I do think that you need to write more about this topic, it may not be a taboo matter but generally people don't speak about these topics. To the next! Best wishes!!


    June 15, 2021 at 16:28 | Report abuse | Reply
  12. RV Repair Nearby

    You are so awesome! I don't suppose I have read a single thing like this before. So great to find another person with a few original thoughts on this topic. Seriously.. thanks for starting this up. This web site is something that is needed on the web, someone with a little originality!


    June 15, 2021 at 21:47 | Report abuse | Reply
  13. RV Repair Shops Near Me


    June 15, 2021 at 22:58 | Report abuse | Reply
  14. RV Repair Near My Location

    Everything is very open with a precise clarification of the issues. It was really informative. Your website is very helpful. Many thanks for sharing!


    June 16, 2021 at 00:18 | Report abuse | Reply
  15. RV Repair Huntington Beach


    June 16, 2021 at 00:25 | Report abuse | Reply
  16. RV Repair Near Me

    I have to thank you for the efforts you have put in writing this site. I really hope to view the same high-grade blog posts by you later on as well. In truth, your creative writing abilities has encouraged me to get my own site now 😉


    June 16, 2021 at 00:29 | Report abuse | Reply
  17. RV Repair Near My Location

    You are so interesting! I don't suppose I have read a single thing like that before. So nice to discover another person with a few genuine thoughts on this topic. Seriously.. many thanks for starting this up. This site is something that is required on the web, someone with a bit of originality!


    June 16, 2021 at 04:27 | Report abuse | Reply
  18. RV Repair Places Near Me


    June 16, 2021 at 04:49 | Report abuse | Reply
  19. RV Repair Places Near Me


    June 16, 2021 at 10:18 | Report abuse | Reply
  20. RV Repair Shop Near Me

    I seriously love your site.. Pleasant colors & theme. Did you create this website yourself? Please reply back as Iím attempting to create my own website and would love to learn where you got this from or just what the theme is called. Many thanks!


    June 16, 2021 at 12:23 | Report abuse | Reply
  21. cvs pharmacy near me


    June 16, 2021 at 15:12 | Report abuse | Reply
  22. obgyn near me

    An impressive share! I've just forwarded this onto a friend who had been doing a little research on this. And he in fact ordered me breakfast due to the fact that I discovered it for him... lol. So allow me to reword this.... Thanks for the meal!! But yeah, thanx for spending the time to discuss this matter here on your site.


    June 16, 2021 at 17:13 | Report abuse | Reply
  23. pizza delivery near me

    Great info. Lucky me I discovered your website by chance (stumbleupon). I've book-marked it for later!


    June 16, 2021 at 17:59 | Report abuse | Reply
  24. car parts near me


    June 16, 2021 at 19:45 | Report abuse | Reply
  25. chevy dealer near me


    June 16, 2021 at 20:43 | Report abuse | Reply
  26. dennys near me


    June 16, 2021 at 20:54 | Report abuse | Reply
  27. used trucks for sale near me

    The very next time I read a blog, I hope that it won't disappoint me as much as this one. After all, I know it was my choice to read through, nonetheless I genuinely believed you would probably have something interesting to say. All I hear is a bunch of whining about something that you could possibly fix if you weren't too busy looking for attention.


    June 16, 2021 at 21:39 | Report abuse | Reply
  28. ankara escort

    Your way of describing everything in this piece of writing is really good, every one can easily be aware of it,
    Thanks a lot.

    June 16, 2021 at 22:59 | Report abuse | Reply
  29. Sprinter Repair Shop Near Me


    June 16, 2021 at 23:31 | Report abuse | Reply
  30. RV Repair Near My Location


    June 17, 2021 at 01:30 | Report abuse | Reply
  31. mesin cetak bakso pentol

    Somеbody essentially һelp t᧐ make severely articles I ѡould ѕtate.

    Thіs is tһe first tіme I frequented yߋur web ρage and sо far?
    І surprised ᴡith the analysis you mɑde to create this
    actual publish extraordinary. Magnificent activity!

    June 17, 2021 at 02:32 | Report abuse | Reply
  32. pizza deals near me


    June 17, 2021 at 02:43 | Report abuse | Reply
  33. wawa near me


    June 17, 2021 at 04:24 | Report abuse | Reply
  34. RV Repair Shops Near Me

    Greetings! Very helpful advice in this particular article! It is the little changes that make the largest changes. Thanks for sharing!


    June 17, 2021 at 04:53 | Report abuse | Reply
  35. RV Repair

    Way cool! Some extremely valid points! I appreciate you writing this write-up plus the rest of the website is also very good.


    June 17, 2021 at 05:51 | Report abuse | Reply
  36. Sprinter Repair Near Me

    Everything is very open with a precise clarification of the issues. It was truly informative. Your website is very helpful. Thanks for sharing!


    June 17, 2021 at 07:44 | Report abuse | Reply
  37. RV Repair Nearby

    I was able to find good information from your blog articles.


    June 17, 2021 at 11:15 | Report abuse | Reply
  38. Sprinter Repair Near Me


    June 17, 2021 at 12:34 | Report abuse | Reply
  39. food lion near me

    Hi, I do believe this is an excellent web site. I stumbledupon it 😉 I am going to come back once again since i have saved as a favorite it. Money and freedom is the best way to change, may you be rich and continue to guide others.


    June 17, 2021 at 18:32 | Report abuse | Reply
  40. bookstores near me


    June 17, 2021 at 19:26 | Report abuse | Reply
  41. navy federal near me


    June 17, 2021 at 19:54 | Report abuse | Reply
  42. nissan dealer near me

    This is a topic that's close to my heart... Many thanks! Exactly where are your contact details though?


    June 17, 2021 at 21:33 | Report abuse | Reply
  43. dodge dealer near me


    June 18, 2021 at 01:28 | Report abuse | Reply
  44. metropcs near me


    June 18, 2021 at 02:29 | Report abuse | Reply
  45. bass pro shop near me

    You are so cool! I do not think I've read a single thing like that before. So great to find another person with unique thoughts on this subject. Seriously.. thank you for starting this up. This site is something that's needed on the internet, someone with some originality!


    June 18, 2021 at 04:04 | Report abuse | Reply
  46. kia dealer near me

    Iím impressed, I have to admit. Rarely do I encounter a blog thatís both equally educative and interesting, and let me tell you, you have hit the nail on the head. The problem is something which too few folks are speaking intelligently about. Now i'm very happy I found this in my search for something concerning this.


    June 18, 2021 at 07:09 | Report abuse | Reply
  47. nail salon near me


    June 18, 2021 at 07:19 | Report abuse | Reply
  48. airbnb near me


    June 18, 2021 at 08:54 | Report abuse | Reply
  49. Nearby RV Repair


    June 18, 2021 at 15:47 | Report abuse | Reply
  50. Camper Repair Shop Near Me

    I like it when individuals come together and share thoughts. Great blog, stick with it!


    June 18, 2021 at 20:24 | Report abuse | Reply
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Leave a Reply to highprolawyer


CNN welcomes a lively and courteous discussion as long as you follow the Rules of Conduct set forth in our Terms of Service. Comments are not pre-screened before they post. You agree that anything you post may be used, along with your name and profile picture, in accordance with our Privacy Policy and the license you have granted pursuant to our Terms of Service.

About this blog

Get a behind-the-scenes look at the latest stories from CNN Chief Medical Correspondent, Dr. Sanjay Gupta, Senior Medical Correspondent Elizabeth Cohen and the CNN Medical Unit producers. They'll share news and views on health and medical trends - info that will help you take better care of yourself and the people you love.

June 2012
  • An error has occurred, which probably means the feed is down. Try again later.