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Through thick and thin

Hair Thickness & Genetics

By now, you might already know whether you have thick hair. Maybe you've been known to snap a brush handle or two when pulling it through your hair. But did you know that individual hair strands come in different sizes, and some people have thicker strands than others? Through thick and thin, your genes influence hundreds of your traits and hair thickness is one of them.

How it works

Hair follicles come in different shapes and sizes, affecting hair texture and width. Some people have wider follicles-and therefore, thicker hair strands-than other people. Genetics influence hair thickness, but other factors like hormones and age are important factors, too.

The genetic link

Scientists think many genes contribute to hair thickness. Research indicates that the EDAR gene, which influences hair follicle development, plays an important role in determining hair thickness.

thick versus thin hair follicles

Did you know?

If you're of East Asian descent, you probably have thicker strands of hair than your friends of African or European descent.

Explore more

Curious to see what your genes have to say about your strands? 23andMe's Health + Ancestry Service can give you a closer look. Order a kit and find out whether your DNA predicts you're likely to have thick or thin hair.

Health + Ancestry Service Kit

Health + Ancestry

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