Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Keratin And the White of Your Nail

  1. Feb 25, 2013 #1
    Why are only the ends of our fingernails white? What causes them to grow that way?

    I'm sure it has something to do with the proteins in our nails.
  2. jcsd
  3. Feb 25, 2013 #2


    User Avatar
    Staff Emeritus
    Science Advisor

    The only living part of the nail is the proximal end (the opposite end to the fingertip) and this is where a nail is synthesised and extruded. You can see this clearly if you ever damage your nail and watch over a period of days/weeks as the damaged portion gets closer to your fingertip before growing out.

    I've looked into it but can't find any specific term for the portion of the nail plate that extrudes over the fingertip however I'm pretty sure that the reason it is white is because that's the colour of nail. The reason the rest is pink is because the tissue underneath the white, translucent nail is pink. If you've ever seriously damaged a nail to the point of large sections/all of it falling off you can see this clearly.

    For further reading on nail anatomy try this reference
    Last edited: Feb 25, 2013
  4. Feb 26, 2013 #3
    It's just called the free edge, inferior portion of it (transverse plane) is called hyponychium. Keratinized tissue of the nail is indeed milky white all along its length, and the pinkish color of the nail's body is due to rich capillary bed underlying it.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook