(knuckles cracking)
- [Voiceover] If you're like most folks,
someone in your life has probably
told you at one point,
cracking your knuckles will mess up your hands...
forever.
How can something that feels so right be wrong?
Is cracking your knuckles actually bad for your health?
When you crack your knuckles,
you're not actually cracking anything.
Between your joints,
there's an egg white-like substance
called synovial fluid.
Gross, I know.
One of the things it does is help
reduce friction when your joints move
by acting as a lubricant.
Scientists used to think that the
cracking sound was the result of
bubbles popping in the synovial fluid.
But this year, doctors were able to record this
video of a knuckle cracking for the first time.
They found that the crack you hear
is actually the sound of a cavity forming.
Nothing is being broken or damaged
except maybe your loved one's tolerance for you.
A study published in 2011 tracked 215 adults
ages 59-80 for five years
and found no link between cracking your knuckles
and the onset of arthritis.
And this guy over here, Dr. Donald Unger,
took it upon himself to crack the knuckles
only in his left hand for 60 years.
He found that the knuckle cracking
hasn't made any significant difference between his hands.
We can all learn something from Dr. Unger,
something called dedication.
So fear not intrepid youths!
Based on the science,
cracking your knuckles is probably fine.
Ooh, ooh yeah!
Ooh, that's the stuff!
(electronic chiming)