Jane: This is But Why: A Podcast for Curious Kids from Vermont
Public. I'm Jane Lindholm. On this show, we take questions
from curious kids just like you, and we find answers. Here in the
United States and in other countries in the Northern
Hemisphere, we're entering summer. In the summer, the sun
is out longer and the weather warms up, so it's a great time
to play outdoors. I like taking long hikes and runs, going to
baseball games and having picnics when the weather
cooperates here in Vermont. But just as you're about to run out
the door to go play outside, you have probably had this
experience: an adult telling you "hold on, you got to put on your
sunscreen." Lots of you have asked us, what's the deal with
sunscreen? Why do we need to put this thing on our skin that
sometimes feels cold and clammy? Well, we have a guest today who
can give you all the tips you need for summer outdoor fun.
Dr. Yu: My name is Dr. Jeff Yu, and I am a dermatologist and
pediatric dermatologist at Massachusetts General Hospital
here in Boston, Massachusetts.
Jane: A dermatologist. What's that?
Dr. Yu: I am a skin doctor. I am somebody that looks at people's
skin, and I diagnose various types of diseases, and I give
information about how best to protect your skin to my patients
small and large.
Jane: What's cool about skin?
Dr. Yu: It's certainly the largest organ of the body. It
covers your entire body, and it grows with you as you get older.
Not only does it include just your skin, but we also think
about hair, we also think about nails. So there is a lot to it
that we are experts in.
Jane: We wanted to talk a little bit about sun safety today and
how we can make sure that we are keeping our skin and our whole
bodies safe during the summer season.
Gilad: My name is Gilad. I live in Israel. What is a sunburn and
how does sunscreen work? I'm two and a half.
Evie: My name is Evie, and I live in Lyman, Maine and I'm
five years old. Why does sun give you sunburn?
Charlie: My name is Charlie. I live in Sarasota, Florida, and
I'm six years old. Why do people get sunburned? And why do we
have to wear sunscreen? And how does the sunscreen make it so we
don't get sunburned?
Jane: So let's first talk about what is a sunburn?
Dr. Yu: A sunburn is something that happens on your skin after
your skin has been exposed to a lot of sunlight. And when you
get a sunburn, the cells on top of your skin, and you have a lot
of those cells, get damaged by the sun and they get burned, but
by the light that is produced by the sun, called ultraviolet
light. So when you get too much ultraviolet light, your skin's
not so happy about it, and it ends up being burned. When you
get a sunburn, the skin turns red, a common sensation that
probably many of us have had, and it hurts when you touch it.
It feels hot to the touch, and after about a few days or a week
or two, you start to notice some of those dead skin cells kind of
peeling off or sloughing off, and the new skin comes in from
below it. People who have darker skin tend to be more protected
from sunburns, because if you imagine the color in your skin
cells acting as kind of an umbrella, protecting your skin
from those ultraviolet lights, or from those sun rays, it is a
little bit harder for people who have darker skin to get a
sunburn, but not impossible, and folks who have lighter skin
cells just don't have that type of protection, and they can get
sunburned more easily.
Jane: if you get a sunburn and then you get over it, is there a
problem?
Dr. Yu: Short term, your body has an amazing ability to heal
itself, so short term, probably not a huge issue. But if you're
someone who grew up getting sunburned over and over again
every single summer, this leads to many problems when you get a
little bit older. So when people are in their 30s and 40s and
50s, one of the first things that we as dermatologists really
worry about is the increased risk of developing skin cancers.
So these are these abnormal growths that can show up on the
skin, whether they're a lump, whether they're a bump,
something that is bleeding, uncomfortable, can be painful,
and if they're untreated, they can grow bigger and bigger, and
sometimes they can travel to other parts of your body, and
they can really cause health problems down the road. So we
tend to see this more in people who had a lot of sun exposure,
especially sunburns when they're younger.
Jane: Dr. Yu says when it comes to protecting our skin,
practicing sun safety and avoiding sunburns is key. We'll
talk more about the different things we can do to play safe in
the sun in a couple of minutes. But before we get to that, when
your skin is exposed to the sun, sometimes there's something else
that happens that's a little bit different from a sunburn.
Sometimes, instead of your skin turning all red and itchy, it
just gets a little darker. People call this a tan. And
Dylan, who's four, is wondering, how does our skin get tanned?
Dr. Yu: Yeah, that's a great question. In your skin cells,
there are these very specific type of cells that are kind of
scattered among them, called melanocytes. These are special
types of cells that contain the ability to produce a type of
color in your skin called melanin. And when you get a lot
of sun exposure, these melanocytes kind of eat it all
up, and they get really happy, and they start making more of
this chemical called melanin that is supposed to be used to
protect your skin against sunlight. So these are the
little umbrellas that I was talking about earlier that
people who have darker skin tend to have more of in their cells,
and the purpose of them is to kind of reflect that sunlight or
deflect it and prevent it from damaging the cells. So when your
skin gets a lot of sunlight, it sees this as a signal to make
more of the melanin. And the more melanin you make, the
darker your skin becomes.
Jane: So should you go out first thing in the spring and summer
and try to get really tan so that you're protected against
getting sunburns?
Dr. Yu: So that's a very common question that I get asked by my
patients. And the short answer is no, because every time you
are getting a tan, you are exposing yourself to large
amounts of ultraviolet rays or sunlight.
Jane: So one of the ways that I've been thinking about the way
your skin changes color is a little bit like when you put
bread in a toaster, and if you toast it a little bit, it gets a
little bit of a light kind of caramel color. If you toast it a
little longer, it gets a little bit darker. And if you toast it
for too long, it burns. Is a similar thing happening with our
skin?
Dr. Yu: Absolutely, you know, you can always do too much, but
even a little bit, even a little bit of heat or a little bit of
exposure, that doesn't mean that you are sparing your cells from
getting damaged. You are still damaging your cells to a certain
degree, just not enough to the point where you are burned.
Jane: Okay, so then one of the main ways that we can protect
our skin, if it's exposed to the sunlight, is by wearing
sunscreen. What is sunscreen and how does it work?
Ida: My name is Ida. I am six years old. I live in Portland,
Oregon. What's in sunscreen that makes you not get a sunburn?
Jack: My name is Jack. I live in Holliston, Massachusetts. I'm
five years old. If you don't put sunscreen on, why will you get a
sunburn? But if you do put sunscreen on, why will you not
get a sunburn?
Dr. Yu: Yeah, so sunscreen is something we recommend to all
kids, no matter your age, whether you are an infant, if
you're a toddler, if you are an adolescent, if you're a
teenager, and even my adults that I see at my work who are 90
plus years old, I still recommend that they wear
sunscreen. So sunscreen, in essence, is just a type of
lotion that you put on your skin to protect your skin from the
light. It's almost like putting on invisible armor to protect
your skin from the harmful effects of sunlight and
ultraviolet rays. We often recommend people to use
sunscreen starting in the springtime and then extending it
through the summer into the fall, and then sometimes even
into the early winter, when the sun can still be strong enough
to cause both tanning as well as any sort of a sunburn.
Jane: If you've ever been in the sunscreen aisle in a store, you
might know there are lots of different options to choose
from. We asked Dr. Yu to walk us through the different types of
Dr. Yu: Sunscreen is not all made the same, so how do you
sunscreen.
pick which one to use? There are two main types of sunscreen that
are out there. One of them is called a chemical sunscreen, and
the other one is called a mineral sunscreen. The chemical
sunscreens like to go on very clear. They tend to rub in very
nicely into the skin. And the reason for that is because
chemical sunscreens include these chemicals that are made to
go into your skin cells. Mineral sunscreens are the ones that
tend to go on a little bit whiter, and the reason for that
is because the minerals used in these sunscreens do not get
absorbed into the skin. The most common minerals that you are
going to see in mineral sunscreen is either titanium or
zinc. Both of these are different types of metals, and
these are really small, tiny, little metal particles, zinc and
titanium, that will then sit on the top of your skin. So
chemical goes in, but the mineral sunscreen sit on top of
your skin, and they actually deflect the light. So imagine if
you have these little particles, these little glass-looking
things that the light shines on, and it just kind of shoots that
light right off of your skin, so preventing the cells underneath
it from coming in contact with the ultraviolet light.
Jane: Sometimes, too, with zinc sunscreens or mineral
sunscreens, you don't have to get white ones. And in my
family, we have a lot of fun with some colorful mineral
sunscreen, and we put it on our bodies to make patterns that are
pink or blue or, you know, yellow and green.
Dr. Yu: Yes, that's really fun for the kids to put it on in
different colors, and then sometimes for kids who might
have darker skin tones, you know, one of the other things
that some companies have done a really good job with is actually
making tinted mineral sunscreens that will then match your skin
tone much better than some of these more traditional mineral
sunscreen that just come out chalky white. So I would
definitely encourage kids and parents to kind of look for
these.
Jane: When you talk about the mineral sunscreens having zinc
or titanium, I think of titanium kind of seems like something a
superhero would use, and you're putting titanium all over your
body, it makes me feel like maybe I'm a superhero, and then
deflecting all of the sun's rays when I'm wearing it.
Dr. Yu: Absolutely, yeah, and that is a great way to put it.
Jane: Coming up, we tackle other sun safety questions like why
are adults always telling us we need to drink water? And our
sunglasses just for looking cool? Stay with us.
This is But Why: A Podcast for Curious Kids. I'm Jane Lindholm.
Today, we are talking with pediatric dermatologist Dr. Jeff
Yu. He's a skin doctor. He's helping us learn how to keep our
bodies protected when we play outside this summer. We were
just talking about why it's important to wear sunscreen when
we go play in the sun, and that's because it protects us
from ultraviolet rays that can damage our skin. But a few of
you pointed out to us that when you put on sunscreen, it can
feel... not great.
Emerson: Hi, my name is Emerson. I'm six years old. I live in
Oakville, Canada, and my question is: why is sunscreen so
cold?
Zip: My name is Zip. I live in Waitsfield, Vermont. Why is
spray sunscreen so cold?
Dr. Yu: You know, the bottle the sunscreen is usually kept in. It
doesn't allow a lot of light or heat into the bottle itself. So
therefore, it's probably going to be a little bit cooler than
where you are, whether that's at the beach, whether that is out
on a grassy field, or if you're by a river, or wherever you are,
where it's much hotter. So that sunscreen is going to feel like
it is much colder when it first comes out of that jar or that
tube, and when it goes onto your skin.
Ellis: My name is Ellis, I'm four years old. I live in San
Francisco. Can hair get sunburned?
Jane: Can hair get sunburned?
Dr. Yu: Hair cannot get sunburned because hair is not
made out of these live skin cells that you kind of have on
your arm or on your hand or on the back of your neck. So hair
itself cannot be sunburned. However, your scalp can
absolutely be sunburned. So if you are someone who maybe has a
very short haircut and there's a lot of your scalp that is
exposed, or if you are wearing your hair in such a way with a
very wide part down the middle and your scalp is exposed, you
can absolutely get sunburned on your scalp. So in the
summertime, we often recommend people to wear a hat of some
sort, whether it's like a bucket hat or a hat with flaps on the
side or nice wide brim, because not only can the hat itself
protect your scalp from the sun, but the brim can protect your
face, for example, your ears, back of the neck, from getting
too much sun exposure and be sunburned.
Jane: Here's a related question about protecting our eyes from
the sun.
Benson: My name is Benson. I live in Richmond, Texas. I'm
four years old. How do sunglasses work that protect
your eyes from the sun?
Dr. Yu: So sunglasses are a great way to not just look cool,
but also to kind of protect the skin around your eyes and your
actual eyes from the sun. So like your skin, your eyes can be
damaged by too much sun exposure. If you're constantly
looking into the sun, or the sun is reflecting off a surface,
kind of like the ground or the water, or if you're skiing and
the sun is kind of bouncing off of the snow and hitting your
eyes, all of those things are exposing your eyes to
ultraviolet light. Not only can ultraviolet light damage skin
cells, it can also damage the cells in your eyes. So using
sunglasses is a really good way to prevent you from suffering
from some of these side effects of too much ultraviolet
exposure.
Jane: I guess sunglasses are better than trying to wipe
sunscreen directly onto our eyes. I don't know about you,
but I hate it when sunscreen gets in my eyes. It stings. So
sunglasses are a much better way of doing it.
Eli: My name is Eli, and I'm from Arlington, Vermont. And I'm
seven years old. Why does the earth look different when you
put sunglasses on?
Jane: Eli is wondering why everything looks so different
when you put sunglasses on.
Dr. Yu: So sunglasses are made out of special lenses that are
tinted or colored in different ways. A lot of these kind of
tinting can make what you see different, because imagine
you're kind of putting on either a brown filter or a green filter
or a red filter or something. So everything around you starts to
look like that color. So that's why things look different when
you're looking out from the sunglasses. But more
importantly, those lenses on the glasses are able to filter
ultraviolet light, just like what sunscreen is doing. So when
the sunlight goes through those lenses, all the bad ultraviolet
light kind of gets filtered out or gets eliminated, and
therefore what is actually reaching your eye is a much
safer amount of ultraviolet light. So therefore wearing
sunglasses, especially if you're on the water, if you're skiing,
or if it's just a really bright and sunny day, that can really
protect your eyes from too much light exposure.
Jane: So as we talk about how we should take care of our skin and
bodies this summer so we can play as hard as we want and for
as long as we want outside, another thing kids often hear
their adults say is "make sure you drink water." Or some adults
might use the word hydration, like, "stay hydrated."
Nico: My name is Nico, and I am four years old. Why does my mom
ask me to stay hydrated?
Lily: My name is Lily, and I'm three years old. I live in
Dallas, Texas. Why does Baba say it's always good to hydrate? Is
that true?
Dr. Yu: So your body is actually mostly made out of water. So
there is a lot of water in your body between the cells, in the
cells, between your organs, in your blood vessels, there is a
lot of water or fluid. And in the summertime, what you might
notice when you're out there playing around is you're
sweating, and sweat is the process with which your body
kind of tries to cool itself off, just like the reason you
get into a pool or into the ocean in the summertime is
because you get water on you, and then that water on you makes
you feel cooler. So your body tries to cool itself off by
sweating, by producing water that then will kind of soak your
face, your arms, your hands, whatever it is so you start to
cool down. But when your body does that, you are losing a lot
of water from your skin, from the bloodstream and from other
parts of your body. So when you start to lose too much water,
you can get what's called dehydrated, or there's not
enough water in your body. And when you get dehydrated, a lot
of bad things can happen to you, where you start to feel dizzy,
you might start getting a headache, you might start to
feel sleepy, some of your body organs might not work normally.
People who are dehydrated also feel really tired, so you may
not be able to run as far or jump as high in the summertime.
So drinking water is really good for you, just to make sure that
you do not get dehydrated in the summertime.
Jane: So Dr. Yu, we've talked a lot about the sun and how to
make sure that you're protecting yourself, and it starts to feel
like if I'm not drinking enough water, or I don't have sunscreen
on, or if the sun is out, maybe I should be worried, and maybe I
should just avoid going outside altogether. Because the sun
sounds dangerous. Should we be scared of the sun? How should we
think about protection without thinking, danger?
Dr. Yu: I do not think you need to be scared of the sun. The
sun's been around for millions of years, and it's going to be
around for millions more, and people for as long as you know
have lived, have really taken to having a good time in the sun
and doing so safely. So I absolutely do not think you need
to be afraid of the sun. I do think when you are in the sun,
practicing sun safety is the best way to go about making sure
that you are enjoying the summer, enjoying the sun, and
really being able to spend time with your friends in nature,
which I think is really important. The way that I would
think about it is, if you can, try to practice more sun safety,
maybe even a little bit of seeking shade and sun avoidance,
especially between the hours of 10am to 4pm during the day. That
is when the sun is the strongest. That doesn't mean you
can't be outside, but maybe if you're able to find areas under
trees where there is shade, or if you're at the playground and
there's a nice shaded area that you can play in, or if you're
having a picnic and finding a nice shady spot that might not
be a bad idea, because that can protect you from the sun. During
those hours, it is also very important to make sure that you
are using sunscreen, making sure that you are reapplying the
sunscreen every you know, 40 to 80 minutes, depending on what it
says on the bottle, and/or wearing clothing that offers you
some sort of ultraviolet protection factor or UPF, such
as a hat, a shirt, pants, things that will protect your skin from
the sun. But I do not think you need to be afraid of the sun.
Before those hours, so before ten o'clock in the morning,
after four o'clock in the afternoon, the sun's a little
bit weaker. That's not to say the sunlight is not out there,
but it's a little bit weaker. And therefore, perhaps you don't
need to be as, you know, focused on finding shade. But I still
would encourage you to wear sunscreen and wear protective
clothing, just so you can stay as sun smart and sun safe as
possible.
Jane: Thanks to Dr. Jeff Yu, pediatric dermatologist at
Massachusetts General Hospital. Now put on some sunscreen, grab
a hat and a water bottle and go play outside. We're putting this
episode out on Friday, June 13th. If you're in the Northern
Hemisphere, you'll have the longest day of the year a week
from now, which is a day called the summer solstice. If your
family has a special way to celebrate the solstice, we'd
love to hear it. You can send us a voice recording or a video and
email it to questions@butwhykids.org. As
always, if you have a question about anything that you want us
to tackle, have an adult record you asking it, and then have
your adult email the file to the same place:
questions@butwykids.org. But Why is produced by Melody Bodette,
Sarah Baik and me Jane Lindholm at Vermont Public and
distributed by PRX. Our video producer is Joey Palumbo, and
our theme music is by Luke Reynolds. If you like our show,
please have your adults help you give us a thumbs up or a review
on whatever podcast platform you use to listen to us. We'll be
back in two weeks with an all new episode. Until then, stay
curious... and hydrated!