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  • Your nails can tell you a surprising amount about your healthwhether you have an

  • infection or a serious illness, for example.

  • But not all weird-looking spots on your nails are that big of a deal, including one of the

  • more common issues: white lines or spots.

  • They might seem concerning, especially if you spend too much time on WebMD.

  • But good news: these little lines and spots are benign!

  • Most of the time, anyway.

  • The formal name for the discoloration is punctate leukonychia, also sometimes called milk spots.

  • There are a lot of myths about what causes these white spots: some people say they're

  • a sign of calcium deficiency, or maybe a zinc deficiencybut neither of those things are true.

  • Instead, white lines that go across the nail, parallel to the nail bed, are usually a sign

  • of trauma to the nail.

  • Meaning, you probably hit your nail, or you bumped it against a desk or a table.

  • The trauma may have been slight enough that you hardly noticed it happened, and quickly forgot about it.

  • But the matrix at the base of the nail, which makes new nail cells, got a bump.

  • That bump disturbed the nail-making process, and it shows in the form of a white spot or white line.

  • But nail growth takes a while.

  • Your fingernails only grow about 3.5 millimeters a month, so it takes some time for the line

  • to appear.

  • As the nail grows, the line moves closer to the tip of your finger, until you eventually

  • clip or file it off.

  • And in the meantime, it's nothing to worry about.

  • Probably.

  • White lines that run across your nail might be the ghost of an old bump, but they can

  • also indicate a fungal nail infection, or an infection with a high fever like measles,

  • malaria, or leprosy.

  • When your body is fighting a severe illness, it shifts priorities from stuff like growing

  • nails to the more important task of keeping you alive.

  • So the white lines on your nails show what's essentially a temporary pause.

  • But by the time the lines showed up, you'd already know you'd been sick from all of

  • the other, much more unpleasant symptoms of these diseases.

  • If you have whitish bands running parallel to your nail bed on all your fingernails,

  • you might have what are known as Mee's Lines, a sign that you've been poisoned by

  • lead or arsenic.

  • These lines are actually deposits of lead or arsenic in the nail.

  • They usually appear two months after the poisoning, so again, by the time you'd see them,

  • you'd probably already know you'd been poisoned.

  • So if you see white lines on your nails and nothing else seems to be wrong, you are probably fine.

  • But of course, check with your doctor if you're worried.

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  • answers coming.

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Your nails can tell you a surprising amount about your healthwhether you have an

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