YouTube: https://youtube.com/watch?v=35cgB5Z3GJs
Previous: Why Do I Get Wrinkly Fingers in the Bath?
Next: Armadillos: Animals with Armor!

Categories

Statistics

View count:91,647
Likes:374
Dislikes:12
Comments:71
Duration:02:55
Uploaded:2017-09-28
Last sync:2019-06-16 03:40
Hair can be so many different colors, but why do so many adults have gray hair?

Hi there! We at SciShow want to learn more about you and your opinions! If you have time, please take a moment to fill out this survey: https://www.surveymonkey.com/r/SciShowSurvey2017
Thank you!
----------
Love SciShow Kids and want to help support it? Become a patron on Patreon:
https://www.patreon.com/scishowkids
----------
Looking for SciShow elsewhere on the internet?
Facebook: http://www.facebook.com/scishow
Twitter: http://www.twitter.com/scishow
Tumblr: http://scishow.tumblr.com
Instagram: http://instagram.com/thescishow

SOURCES:

http://www.webmd.com/skin-problems-and-treatments/picture-of-the-hair#1
https://www.ncbi.nlm.nih.gov/pubmed/21466661
http://kidshealth.org/en/kids/gray-hair.html
http://www.iflscience.com/health-and-medicine/why-does-hair-change-colour-and-turn-gray/
Squeaks and I love learning more about how our bodies work, and he just asked me a great question: Where does gray hair come from?

Lots of grown-ups have gray hair, but it wasn’t always gray. Everyone who has gray or white hair used to have hair that was a different color, like blonde or brown, or red Hair turns gray as people get older, because the stuff that gives their hair its color starts to run out.

Each hair we have grows from its own little spot under our skin, called a follicle. A follicle is like a tiny hair-making factory, putting together fibers to make the strand of hair and adding color to it. That color comes from something called melanin, which is kind of like hair dye that our bodies make by themselves.

It can be all kinds of different shades of blonde, red, brown, or black. That’s why people’s hair can be lots of different colors — it just depends on the types of melanin they have. We have melanin in other parts of our bodies, too.

It gives color to our skin, and even our eyes! There are lots of little tiny things inside hair follicles, called melanocytes, that are always making more melanin. Every day, the follicle adds more fibers to the bottom of the hair, so the strand gets a little longer.

At the same time, it uses melanin from the melanocytes to color the hair. That’s how our hair grows! But each hair doesn’t grow forever.

After a few years, it falls out, and the follicle starts over with a new hair. Now, that doesn’t happen to all of our hair at once — only a few hairs fall out and start growing again every day, which is why you might not even notice it happening. But every time the hair falls out, the follicle also loses a few of the melanocytes that were making the melanin.

Our bodies can make enough melanocytes to keep growing and coloring new hairs for a very long time. But after lots of years of growing new hairs, the follicles start to run out. They can still make the hair itself, but without melanocytes, they can’t make the melanin to color it anymore.

And guess what the hair looks like without the color? [Squeaks guesses] Exactly! Without color from melanin, hair is gray or white. At first, just a few hair follicles run out of melanin, so the person only has a few gray hairs.

As more and more follicles run out of color over time, they get more gray, until eventually all their hair is gray. You probably have a loooong time before your hair goes gray, though. Everyone’s different, but people usually get their first few gray hairs when they’re around 30 or 40 years old, and most of their hair is gray by the time they’re 50 or 60.

Some people decide to dye their hair a different color when it starts turning grey but lots of people keep it grey or white So, Squeaks, there’s your answer. Going gray is just a normal part of getting older! Thanks for joining us!

If you want to keep learning and having fun with Squeaks and me, hit the subscribe button, and we’ll see you next time here at the Fort!