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Cartilage turning into bone

How Do You Grow Taller?

Bones lengthen at soft zones near their ends, mostly while you are asleep, until those zones close for good.

1 A soft zonenear each end2 New cartilageis added atnight3 It hardens intobone — you aretaller
Not stretching. Building.
  1. Step 1 of 5

    Bones do not stretch, they lengthen at the ends.

    A thigh bone A soft growth plate neareach end

    Near each end of a long bone sits a plate of cartilage. New cartilage is added on one side and turned into hard bone on the other.

  2. Step 2 of 5

    Most of the work happens while you sleep.

    Growth hormone at nightbig pulses indeep sleepGrowth hormone by daysmall trickle

    The hormone that drives growth is released in pulses, and the biggest pulses come during deep sleep. Sleep is not optional for growing.

  3. Step 3 of 5

    You really are taller in the morning.

    Morning Discs full — slightlytallerEvening Discs squashed — a bitshorter

    The discs between your vertebrae squash under your own weight all day and swell back overnight. It is about a centimetre, and it is not growth.

  4. Step 4 of 5

    Growth comes in bursts, not smoothly.

    1 Steady growththroughchildhood2 A fast burst inthe teens3=Then it levelsoff

    Children can add several centimetres in a few months and then almost nothing for a year. Aching legs during a burst are common and normal.

  5. Step 5 of 5

    Then the plates close and it is over.

    Plate open The bone can stilllengthenPlate closed Solid — final heightreached

    In the late teens the cartilage plates finish turning into solid bone. After that a bone can heal and thicken, but it cannot get longer.

    Doctors can read an x-ray of a child's hand and estimate how much growing is left from how open the plates still look.

The short version

You grow at cartilage plates near the ends of your bones, mostly in deep sleep, until those plates harden and your height is final.

Try it yourself

Measure yourself first thing in the morning and again at bedtime. The difference is your spinal discs, not growth.

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