Human Biology

Why Hair Only Grows To A Certain Length

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No matter how hard some people try, they can't seem to grow their hair out to that coveted mermaid length. But why? Hair length is controlled by genetics, hormones, and even extreme stress. Discover the chemical cycle that determines your hair length in the following video, then learn more about hair.

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Hair Length Comes Down To Chemistry

The average length of your hair's anagen phase is two to seven years.

What Makes Curly Hair Curly?

Straight hair has circle hair fibers, while wavy or curly hair has ovals.

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