Kind: captions
Language: en
recently I made a video about what the
world looks like in the ultraviolet some
things look the same but generally it's
hazy err sometimes light and dark are
flipped skin looks blotchy ER and fake
teeth stand out whoa
smile for me oh my goodness you the fake
teeth baby which one
but the idea for this video started a
long time ago with a question I had
which is how does non ionizing radiation
like ultraviolet light damage skin and
lead to cancer I do like to tell people
that if you want to see how good your
skin could look look at your butt
because that's an area that doesn't get
the Sun and even old people have perfect
butts
it's how your skin would age without the
Sun when I thought about what UV light
must be doing to our cells and our DNA I
imagined it would be getting in there
and breaking all these bonds and that
would be the problem but in fact it's
kind of the opposite UV actually
facilitates the formation of covalent
bonds in our DNA that shouldn't be there
it comes in and it kind of creates these
unauthorized bonds between the basis
called primitive dimers instead of
having them bonded across it bonds the
one next to each other if that makes
sense oh yeah so what happens is two
thymines which are side by side can
actually get covalently bonded together
and that creates a lesion on the DNA you
can think of it like a little bump that
makes the DNA hard to read and work with
that's not enough in itself to cause
skin cancer if that were the case we
would just be covered in skin cancers
then the next step is that we have to
repair it and in the repair that's when
you form mutations that could eventually
lead to cancer through bunch of
different pathways and there's actually
people who have specific genetic issues
that they can't repair these issues and
they are covered in skin cancer UV has
other effects on the body like it
suppresses the immune system so as Haley
says it's a double whammy there's also
kind of a double whammy because UV not
only induces these unauthorized bonds
it actually tamps down our natural
immune system so one of the best ways we
fight cancers through our immune system
we have constantly me as surveillance
through our skin so not only a Sun like
creating these problems it's actually
reducing our ability but our ability to
fix them so so unfair UV light also
causes us to visibly age it's called
photo aging I should clear up a
misconception here that I had which was
I thought glass blocks all ultraviolet
light so I thought if you're inside a
car for example you really don't need to
put on sunscreen because you're not
being exposed to UV light the car does
not block UVA glass it does block most
UVB but you're still susceptible to
those sunspots and those wrinkles
through the glass and a lot of my
patients if you look and you compare
their hands the left is is more wrinkled
or has more sun spots on it because
they're driving so they sticking their
hands they're gonna hand out their
truckers absolutely you can see it the
worst and there's a really famous
picture of someone whose left side of
their face is significantly more as we
would call it like photo aged old
looking than the other side of their
face so that's mostly UVA and UVB editor
it's a little bit deeper so wrinkles
mostly come from destruction of our
collagen and elastin which is natural
fibers that hold up the scaffolding of
our skin so with age the cells that
secrete collagen they're called
fibroblasts they stop producing as much
and what the Sun does is it breaks down
the existing collagen and elastic so
fibroblasts really like to be stretched
they like to be pulled and collagen does
that that collagen matrix so the Sun
damages the collagen fibers leading to
less stretch on fibroblasts and less
production of collagen which means that
we look a little more saggy I know it's
very depressing so sun protection helps
the degradation of those collagen
elastin fibers you know there are a lot
of creams on the market that claim to be
anti-aging but the one that really works
is sunscreen preventing ultraviolet
light from hitting your skin is the best
thing you can do to avoid skin cancer
and to avoid photo aging
so yeah it's good advice use sunscreen
hey I'm on set for Jurassic world fallen
Kingdom and I'm here filming sci-fi test
lab where we try to recreate some
dinosaur parts out of machinery and test
them out so if you want to see that then
click here