Fingernails and toenails, they're not just for
decoration. They protect your fingers and toes
and help you pick up tiny things, like
splinters or that piece of spinach stuck between
your teeth after lunch. And they can
also tell you a lot about your health.
Nails are collections of dead cells
that grow from a root called a Matrix
hidden just beneath your cuticle,
the lighter crescent shaped area at the
base. The matrix constantly makes
new cells called Plate Cells, and
each layer pushes the old, dead
plate cells out of the cuticle. When nails start to
grow differently or even change color,
it usually means that there is something wrong with the
matrix or with the surrounding tissue. So
by working backward, you can often figure out what's doing
the interfering, and in the process
maybe learn something about what's going on in your
own body.  Beau's Lines, for example,
are horizontal ripples on the surface of the
nail. They look like little waves, and
they form when the matrix stops producing new
cells for a while. When the matrix starts making new
cells again, they push the nail out as usual,
but there is an indentation marking the spot
where it stopped, kind of like a tree ring. And there's a
reason why the matrix would've hit the pause
button. Probably, it wasn't getting
enough nutrients from the blood stream. Usually,
that means the person has an infection or some
other kind of serious illness.
 
That's why people who have high fevers for a while, often
develop Beau's lines a month or two after-
-wards. Pitted nails are another potential matrix
issue, where the nails surfaces have indentations
that look like very small pot holes.
The pits are linked to skin disorders, like
Psoriasis and Eczema, which can cause
inflammation of the matrix. An inflamed matrix
produced new plate cells unevenly,
so you end up with depressions on the nail surface.
Nails can also change color, something
you've probably noticed if you've studied your nails on
a cold day, and realized they were
blue. Generally, that means that your extremities
aren't receiving enough oxygen. Blood with
low oxygen is darker and reflects light
differently through your skin making your nails
look blueish. It could just be your body reacting
to cold by constricting your blood vessels, but a
person whose blood isn't receiving enough oxygen
could have a respiratory illness, like asthma
or emphysema. Blue nails can also be
a sign of Raynaud's Disease. A
disorder marked by spasms in a person's
blood vessels that narrow them. The
narrowing reduces blood flow to the extremities,
so they get blue nails. Now blue nails,
it not actually the nail changing color, it's the bed underneath
it. But nails can also turn yellow,
and that's actually the nail changing color,
this can  happen for a lot of different reasons. In most cases, it's
cause by a fungal infection known as
Onychomycosis. Yeast or mold sets up shop within
the actual nail plate, turning it yellow.
It doesn't smell to good either. Other times,
the yellow nails means something more serious, like Yellow
Nail Syndrome, which doesn't sound super serious,
but it happens when the matrix does
produce new plate cells but very slowly,
so they pile up and create a
thicker yellow-ish nail plate. But like Beau's
Lines, Yellow Nail Syndrome is caused by something
else. It could be a chronic respiratory disease,
which would reduce the nail's oxygen supply
and slow growth. Or it could be sign of an issue with
the Lymphatic system, which distributes protein
rich fluid throughout the body. Usually,
that issue is cancer or aids.
A black or brown streak in a nail can also
be super serious, or nothing
at all. In some people that streak can signal Subungual Melanoma,
a form of skin cancer that affects the nail bed,
which is the skin underneath the nail plate.
Melanoma often changes the color of the skin,
including the skin under nails.
But the streak also might be harmless, if you have a
darker complexion it's completely normal.
 
So it could be something, or it could be nothing.
Which is why of you're worried about the color or the look of your nails, here's a tip.
Don't get all your medical advice from the internet!
These changes can mean more than one thing, so talk
to a real doctor before jumping to any conclusions.
We are not a real doctor.
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