• Question: What makes my hair curly?

    Asked by anon-251077 to Alex on 2 Apr 2020.
    • Photo: Alex Agrotis

      Alex Agrotis answered on 2 Apr 2020:


      Hair shape is affected by your genetics, so that means that if your parents have curly hair there is a good chance you will too. But there are thought to be more than 10 genes that influence hair shape, so there are many different levels of curlyness and it’s not as simple as curly vs straight. Scientists are still trying to learn more about hair shape is controlled by these genes.

      The physical reason for your hair being curly is due to the shape of the individual hair.
      Imagine enlarging one of your hairs to the size of a tree trunk, cutting through it with a saw, and looking at the tree stump from above. For curly hair, the stump would be shaped like an oval or ‘D’ shape. This shape makes the hair more likely to bend in one direction (think how a ribbon likes to curl compared to a piece of string). For straight hair, the stump would be closer to a circle.
      What controls this shape? One idea is that it’s caused by the shape of the hair follicle – the tiny hole in your scalp that the hair emerges from. But there is definitely still more for scientists to understand!

Comments