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Fact or Fiction: Nails
by Staff
Your nails are handy for so many things -- scratching itches, peeling oranges, drumming on tables. But what do your nails say about your health? And what can you do to keep them strong and healthy? Do your hands a favor and take our quiz.

Nails are made of a protein called keratin, the same as animal hooves and horns.

  • fact
  • fiction
  • almost fact: Nails are made of keratin, but hooves and horns are made of calcium.

Vitamin B12 is great for your nails.

  • fact
  • fiction
  • almost fact: It's vitamin B7, otherwise known as biotin.

Walnuts, sunflower seeds and brown rice are good sources of biotin.

  • fact
  • fiction
  • almost fact: Walnuts and sunflower seeds are good, but brown rice doesn't have vitamin B7.

Manicures are generally great for your nails, but you should steer away from polish that contains formaldehyde and toluene.

  • fact
  • fiction
  • almost fact: You can also add dibutyl phthalate to that list.

Your fingernails grow about a millimeter a day.

  • fact
  • fiction
  • almost fact: They grow about half a millimeter every day.

If you completely lose a fingernail, it will take a year to grow back.

  • fact
  • fiction
  • almost fact: It will take about six months.

Your toenails grow twice as fast as your fingernails.

  • fact
  • fiction
  • almost fact: Other way around -- your fingernails grow about twice as fast as your toenails.

If you have black, brown or purple discoloration under a nail that wasn't caused by an injury, it could be a melanoma.

  • fact
  • fiction
  • almost fact: Melanomas don't grow under nails, so it's most likely a blood clot.

The same type of fungus that causes athlete's foot can give you a fungal nail infection.

  • fact
  • fiction
  • almost fact: The athlete's foot fungus can cause problems near your nails, but it won't affect the actual nail.

If you have a fungal nail infection, your nail could turn brown or black.

  • fact
  • fiction
  • almost fact: The nail will turn purplish-blue.