How does hair grow?

Mystery Science2 minutes read

Hair grows from follicles on the head, which turn nutrients into hair material, with each strand made up of piled-up hair material created by the follicles. Hair growth stops after about five years, falls out, and gets replaced by new hair, explaining why hair doesn't keep growing indefinitely. Some people can grow their hair longer as their hair stays on their head longer than average, allowing for more growth time.

Insights

  • Nutrients from food are transformed into hair material by follicles on the head, with the bottom part of the follicle being alive while the hair itself is dead.
  • Hair growth is limited to around five years, after which it falls out and is replaced by new hair; individuals with longer hair retention periods can achieve greater hair length due to extended growth opportunities.

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Recent questions

  • How does hair grow?

    Hair grows from follicles on the head, receiving nutrients from food and turning it into hair material. Each strand is made up of piled-up hair material created by the follicles, with the bottom part of the follicle being alive and the hair material being dead.

  • What happens to hair after five years?

    Hair stops growing after about five years, falls out, and gets replaced by new hair. This process explains why hair doesn't keep growing indefinitely.

  • Why do some people have longer hair?

    Some people can grow their hair longer as their hair stays on their head longer than average, allowing for more growth time.

  • What is the composition of hair strands?

    Each hair strand is made up of piled-up hair material created by follicles, with the bottom part of the follicle being alive and the hair material being dead.

  • How do follicles nourish hair?

    Follicles on the head receive nutrients from food and turn it into hair material, which then grows into hair strands.

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Summary

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Hair growth cycle and length variation explained.

  • Hair grows from follicles on the head, which receive nutrients from food and turn it into hair material.
  • Each strand of hair is made up of piled-up hair material created by the follicles, with the bottom part of the follicle being alive and the hair material being dead.
  • Hair stops growing after about five years, falls out, and gets replaced by new hair, explaining why hair doesn't keep growing indefinitely.
  • Some people can grow their hair longer as their hair stays on their head longer than average, allowing for more growth time.
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