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You heard it over and over again from your mom.
“eat your carrots, they’ll help you see better!”
Well get ready to throw it back in mom’s face,
with science!
(reactions theme)
Actually before we get to the science,
let’s have a history lesson.
During world war two, british pilots
had this fancy new top-secret system for
spotting enemy planes called “radar”.
No not that radar. Look it up, kids.
Our chemist friend chad jones
picks up the story from here:
“this fancy new radar system gave pilots
a huge advantage over their enemy.
To keep this advantage a secret the
british royal air force started a rumor
that their pilots ate lots of carrots to
help them see the enemy better at night.”
Of course it wasn’t the carrots, it was
just the radar, but the rumor actually stuck,
and it still circulates to this day.
And the funny thing is, there’s
actually a bit of truth to it.
Carrots have in them a chemical compound
called beta carotene
(and…no, it’s not named after carrots).
When you eat foods with beta carotene,
your body converts it into vitamin A.
And that vitamin A gets turned into retinol.
Now retinal is found in your eyes
inside vision cells called "rods".
At the very tip of the cell you'll find
retinal wrapped inside of a protein.
That protein is twisted and compact
a little bit like this ball of yarn...
And retinal sits comfortably inside - like
a baby wrapped in a tight blanket. But, when
light shines on this happy, sleeping baby...
It stretches out from this form (called cis)
to this form (called trans).
This stretching unravels the protein,
starting a chain reaction that leads
down the rod cell, through the nerves,
and to the brain letting you know
it's not dark anymore.
And that’s how you see light.
So where does that leave our carrot myth?
Well, any food that has vitamin A will
be good for your overall eye health.
That’s carrots, lettuce, spinach, mangoes,
milk, cheese, cantaloupe and peas.
But if you already have a diet of vitamin A,
these foods won’t actually improve your vision.
So don’t forget your vitamin A,
but don’t count on getting rid of
your glasses any time soon just
because you’re chomping on a carrot.
Big thanks to chad jones.
He hosts a great podcast called
the collapsed wave function,
we’ll include a link in the description.
We talk a lot of food on Reactions.
Check out our video on the chemistry of pizza,
or find out why foods taste sweet.
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