Give Now  »

Noon Edition

The Cause Of Curls

A hair stylist works to achieve a perfect head of curls.

Do you have straight hair and wish you had curly locks? Or maybe wish you could trade in your curls for straight tresses. Either way, have you ever wondered about the science behind your 'do? If so, read on!


How curly or straight your hair is depends on the shape of your follicles, the tiny structures in our skin that produce hair. Round follicles produce straight hair, while curly hair comes from oval shaped follicles.

Keratin is a protein that gives our hair structure. When hair moves through round follicles, it's evenly coated with keratin, all the way around. Hair that grows through oval follicles tends to have more keratin on one side than the other. As a result, it curls.

It's like taking a pair of scissors and running it along that plastic gift wrapping ribbon. As one side gets stretched out more than the other, the ribbon curls in on itself.

A Perm's Temporary Fix

Permanents use chemistry to disrupt the bonds in your hair and then forge new ones when the hairstylist puts your hair in curlers. Because getting a perm does not change the shape of your follicles, however, they eventually grow out, leaving you with straight hair once again.

If there were a way to change your follicles from round to oval, the hair industry would make a killing! And maybe they will figure it out one day. In the meantime, though, you'll have to make due with temporary fixes or learn to be content with the hair you have.

Support For Indiana Public Media Comes From

About A Moment of Science