Is sunlight good or bad for your child's eczema? In this episode of the Eczema Breakthroughs podcast, Dr. Kirsty Rutter, dermatologist and researcher at the University of Manchester, helps parents navigate the confusing world of sun exposure and sunscreen for children with eczema.

She covers when to start using sunscreen on babies, the difference between mineral and chemical filters, and how to choose a broad-spectrum sunscreen that won't irritate sensitive skin. Parents will learn practical strategies for beach holidays, how to layer sunscreen with eczema moisturizers, which eczema treatments increase sun sensitivity, and when to suspect photoaggravated atopic dermatitis. If you're a parent struggling to balance sun safety with eczema care, this episode gives you the expert guidance you need.

Hello and welcome to Eczema Breakthroughs podcast.

Parents of children with eczema are often told two seemingly contradictory

sunlight can be good for eczema and children need to be

protected from ultraviolet light.

What is the truth, and how should parents make that decision

for their individual child?

To help us know how to use sun and sunscreen safely with our children, we

are joined today by Dr. Kirsty Rutter.

She is a dermatologist and clinical senior lecturer at the

University of Manchester in the UK.

She is currently leading research to better understand

how sunlight and ultraviolet radiation affect eczema, including

photoaggravated atopic dermatitis.

and Her goal is to provide more personalized advice, for

patients and for families.

Dr. Rutter, welcome to the podcast.

Thank you, Lynita.

to be with you.

Can we start by answering the question, is

sunlight good or bad for eczema?

Yeah, so that's a really good question, and It seems as if there

are three different ways that people can respond to sunlight with eczema.

some people find that sunlight is helpful for their skin, and their eczema will

tend to improve after sun exposure, sunny holidays, or in summertime.

We know that this can be harnessed as a treatment for instance, in

phototherapy when this is a controlled form of UV treatment that can

be used in clinics and hospitals.

Then there's another group of people who don't necessarily feel that sunlight

makes a difference one way or the other.

And then there's this subgroup that I'm particularly interested in who

seem to have a type of eczema that's made worse by sunlight exposure.

We call this photoaggravated atopic dermatitis, or photoaggravated eczema.

Around three to 15% of people with atopic dermatitis might have eczema

that's made worse by sunlight.

So this really could represent quite a sizable number of people

overall who can be affected.

Sure.

And what about in kids?

We see that it can affect a range of ages, we've seen children

affected and older people affected.

You were saying earlier that some people benefit from sun exposure.

Is it worth having some sun exposure?

And if so, how much?

That's a really difficult question because it depends a lot.

It depends on your skin type, your ethnicity, where you

live, and that kind of thing.

It's really important for children to get outdoors and to be active.

There are really important health benefits to this.

But there isn't really a significant benefit from unprotected sun exposure,

except of course that UVB rays in sunlight are the main way our bodies

can make vitamin D. But you don't actually need very much UVB to

achieve satisfactory vitamin D levels.

So for instance, 10 to 15 minutes of exposure wearing T-shirt and

shorts three times a week can be enough for people with lighter skin.

For people with darker skin, the situation is a bit different.

It's probably harder to make the same amount of vitamin D, and the skin

is less susceptible to UV damage.

So people who have eczema that improves in sunlight, just get a sense to how

much sunlight they can o- obtain without causing sunburn, but helps their skin.

I guess if we have light skin and we live in say Australia, like I'm from,

we probably need to be a lot more careful.

And so a little bit of sensibility comes into play, I guess

Yeah, I think that's absolutely the case.

It's about reaching that balance really thinking about the risk-benefit

ratio, and it is quite difficult.

And yes, of course, it depends on where you live, and I'm in the UK, and in autumn

and winter, we really wouldn't be able to make much vitamin D. And actually, it's

very easy to take a vitamin D supplement, so you don't need to worry so much

about trying to balance the risks and benefits in order to obtain vitamin D.

So we don't just need to get it from sunlight.

Yeah.

let's talk about sunscreens now because this is where a lot of parents

get really anxious about sun exposure.

So When parents have a baby with eczema when is it safe to start using sunscreen?

The guidance isn't really different with eczema and babies

without eczema, so taking precautions to protect babies and children

from the sun is really important.

We know that childhood sunburn increases the risk of the most harmful type

of skin cancer, which is melanoma.

And it's also good to start sun protection habits really at an early age.

So most of what I'm saying here refers again to people with lighter skin, so

people with darker skin have a much lower risk of sunburn and skin cancer.

But, What's really important to remember is that sunscreen is

only one part of sun protection.

Timing your activities, seeking shade, protective clothing, and

hats can be really important and often easier than trying to apply

sunscreen to wriggly babies.

So our current advice is that for infants under the age of six months to focus

mainly on these physical methods rather than extensively applying sunscreen.

And this is partly also because small children have that larger surface area

to volume ratio so there's a higher relative exposure exposure to any

agents which are applied to the skin.

But if there's no way to keep an infant out of the sun, then applying sunscreen

to exposed areas such as forearms, hands, and The face can be used, and I wouldn't

expect that to cause any problems.

and The World Health Organization recommend using sun protection when

the UV index is above three, So in general that would be the

recommendation for babies and children.

For sure.

What if my child has an active flare on their hands and they're

playing outside, What should I do

?? Kirsty Rutter: yeah well, So there are a couple of issues here.

The first is that applying sunscreen to active, inflamed, cracked skin

can be painful, and that could lead to this ingrained fear of sunscreen,

which you definitely want to avoid.

And the second, is to do with absorption of sunscreen across the skin.

So we know that small amounts of sunscreen can be absorbed across the skin and,

although the significance of this isn't currently known, if the skin is very

inflamed or broken, that could increase the absorption of sunscreen chemicals.

So in general, I would probably rely on seeking shade, using clothing, hats,

and so on in this kind of situation.

So we should find other ways to protect the skin if the

skin is open and weeping and oozing.

I think so.

In terms of clothing, it doesn't have to be thick, darker colors and

Tightly woven fabrics protect better.

And obviously you can get some clothing which is specifically

designed to block UV.

But it doesn't have to be expensive, it's possible to choose

lightweight, tightly woven fabrics which can be quite protective.

Sun protective fabrics are great.

But sometimes we can't avoid sun exposure, and that's when we use sunscreen.

Can you explain to us, what types there are, and what is

better for children with eczema?

So sunscreens are primarily designed to stop UV getting

into your skin and causing damage.

At the Earth's surface, around 95% of UV radiation is UVA

and about 5% of it is UVB.

UVB is more capable of causing sunburn, while UVA can penetrate further into the

skin and could cause effects deeper down.

Right.

modern sunscreens now contain a range of different UV filters

to block different wavelengths to provide what we call broad spectrum cover.

So when we talk about sunscreen that is UVA and UVB

protectant, that's usually covered in the term broad spectrum.

And so we want to look for that word, on our sunscreen?

Yeah, it depends a bit where you live.

Sunscreen labeling can vary.

So sun protection factor Is really a measure of UVB to, but uVA is really

one to be aware of because it can come through cloud cover, and it can

come through windows, so it can be a little bit harder to protect against.

The way UVA protection is recorded is a bit different.

So in the UK, for instance, a common system is the Boots star rating which

goes from one to five stars, but that score is relative to the sunscreen's

in Europe you can see UVA in a circle as well, which means that the UVA protection

is at least one third of SPF value.

But in the US, broad-spectrum means that absorption is in the UVA

and UVB range . So it is quite a confusing landscape for consumers.

Yes, so when you're going on holiday somewhere sunny, either

pack sunscreen that you know how to interpret or learn how to interpret

the ratings in different countries.

Yeah

So let's talk about the types of sunscreen filters that are available.

So, um, there are two main categories of sunscreen, which

are the mineral type and chemical.

So the chemical sunscreens work by absorbing UV and converting it into

very small amounts of heat, such small amounts that you don't notice it.

Different chemical filters absorb at different wavelengths, so can combine

them and get quite good broad cover.

Then the mineral filters are usually zinc oxide and titanium dioxide.

And these Work mainly by absorbing and to a lesser degree by

reflecting and scattering the UV.

The earlier mineral sunscreens, they were quite large particles.

So they were very white and it was very obvious that you were

wearing mineral sunscreens.

More recently the particles have made smaller and smaller.

So nano-sized particles make the sunscreens more cosmetically acceptable

and don't leave such a white cast.

So these mineral filters started off as quite big particles,

which left this sheen on your skin.

And because people didn't like that, they started making the particles

smaller and smaller, but does that mean it can get into our skin more?

The concern is not thought to be significant at the

moment, and mineral sunscreens also have another potential advantage.

There's some anecdotal evidence for people with eczema that they might be a bit

better tolerated, and certainly they're less likely to cause allergic reactions.

So I I wouldn't dismiss the concern about nanoparticles, but it's not thought

currently to be a significant issue.

Okay.

So Overexposure to sunlight is a known problem.

whereas With Nanoparticles, it's not something that has

been proven in research to date.

Yeah.

So which do you recommend, mineral or chemical sun filters for eczema kids?

I wouldn't say, Lynita, I necessarily recommend

either mineral or chemical sunscreens, particularly for children with eczema.

So the best sunscreens are a broad spectrum, high SPF product which

the child can tolerate on their skin and which doesn't irritate it.

That can mean you have to try out a few different products to

find the one that, that suits.

Sure

That doesn't mean it has to be an expensive one.

But it is important to find a sunscreen that, your child's happy to use.

I think that's important.

What quantities of sunscreen should we put on our skin?

To achieve that SPF, for an adult person, you need to apply , a

teaspoon for the face and neck, a teaspoon for one arm, a teaspoon for the other arm,

two teaspoons for each leg and the body.

it's quite a large amount, and people are actually applying maybe three or four

times less than that, which means that an SPF SPF might only achieve an SPF of nine.

So you're not, in the real world, probably going to achieve an SPF of 30 and And so

Interesting.

that most of the time I would recommend an SPF of at least

50 just because of the difficulties in applying sufficient quantities.

With my kids school, I would make them put sunscreen on before they

left the house, but they didn't like it.

And so they would put the thinnest, layer on their skin.

And I was like, "No, that doesn't work.

You have to be quite vigilant that they're actually doing it properly.

That's right.

If you're not applying it in those large quantities it just means

you're not going to get that SPF.

Yep.

Okay.

We'll keep a closer eye on my children in future.

A new sunscreen filter has just been released in the US,

but it has been available in Europe and in Asia for a while.

And it's called, bemotrizin-

Bemotrizinol or bemotrizinol.

Yes do you know anything about this sunscreen filter, and would

you recommend it for eczema kids?

Yeah, so it has been available in Europe

since the early 2000s, I think.

It's got several other names too.

It's also called Tinosorb S, bis-ethylhexyloxyphenyl

methoxyphenyl triazine, I think.

It's hard enough to read something like that.

sounds like a spot the difference challenge.

Yeah, it is.

But this the new addition of bemotrizinol this year, it has quite good protection

in UVA and some into the UVB as well.

So if you do see it on a sunscreen bottle, it's worth patch

testing your child's skin because if you're in the US you may not

have been exposed to it before.

Yeah, I think with any sunscreen, it's worth trying out a patch

test, so applying it to a non-inflamed area of skin that doesn't have eczema

for three or four days and just keeping an eye on it to see it doesn't

cause a problem before extending it.

But of course, you're not born with an allergy to sunscreen.

It can develop over time.

So it Is possible to develop a contact allergy to a

sunscreen, like any other product, that you can put on your skin.

Yeah, and you definitely can develop contact allergy or

photocontact allergy, to UV filters.

Other issue is that you can react to other ingredients in sunscreen, so it

might not be the UV filter, so it could be things like fragrance or preservatives.

Sure.

The other issue probably more commonly than allergic

reactions are irritant reactions.

So classically, irritant reactions would be a bit more of an

immediate burning discomfort.

The skin would feel tight and red, and an allergic reaction would take

a little bit longer to develop, but it'd be quite itchy, often quite

swollen, particularly around the eyes, sometimes can even blister.

But it can be quite hard to differentiate between an allergic

and an irritant reaction.

If you suspect sunscreen allergy, worth possibly trying a different product.

I found a paper published earlier this year that looks at the

allergens in sunscreens, and I'll share that link in this podcast.

But the authors developed a sunscreen checker website called the North

American 80, where you can enter your sunscreen ingredient and

check if it's a common allergen.

Yeah.

, It could be really helpful.

It is quite challenging, and I can sympathize with people,

Yeah, and the sunscreens that appear to have the least things

in them that could irritate your skin, like fragrances, were the ones that

contained the word baby written on them Or ones that were for the face.

Yeah.

And sensitive skin is another one that's quite commonly used, or hypoallergenic,

but it's not always very clear what those terms mean and how relevant they are.

Sure.

So broadly speaking, are there specific things that we should avoid like

preservatives or alcohol that should be, red flags for parents with eczema kids?

So I think for eczema kids, alcohol-containing

sunscreens can certainly sting if they're applied to broken skin.

Fortunately, sunscreen allergy isn't all that common.

I would say irritation from sunscreen is probably a bit more

common, particularly if the eczema is going through an active phase.

Okay.

And what we use on our skin, like a spray or a lotion or a stick,

does it make much difference?

I don't generally recommend sprays because so much of them goes

into the atmosphere, and it's really hard to know how much you've applied.

But if that's the only option, then it's better than nothing.

some of the stick forms and the zinc-type products, you can see

exactly where they are, but they're not always so cosmetically acceptable.

When a child wipes it onto the sleeves of their

clothes that they're wearing.

Exactly.

I think the important things, though, you need to be applying

sunscreen liberally to the parts of the skin that will be exposed, and

you're not looking to rub it in.

You need to apply it fairly gently onto the surface of the skin as you might apply

your emollient, but leave it to sit there.

Ideally 30 minutes before you go out in the sun, and then ideally it

should be reapplied so that you make sure you've covered any missed bits.

On a practical matter though, I don't wanna put it on and then have

it rubbed all over the car surfaces.

So, maybe having a little routine where you, have a snack in the shade

while the sunscreen absorbs in before they're already running to the water.

That's a great idea.

Yeah.

if we are putting moisturizer on a child's skin on a regular

basis and then we put sunscreen on, is that gonna be a problem?

Sunscreen should be the last thing that's applied.

So, for instance, if somebody was using a topical steroid and a moisturizer,

they would need to apply a topical steroid, wait, then the moisturizer,

wait, sunscreen, wait, reapply sunscreen, and the gap between the moisturizer or

emollient and sunscreen is recommended to be 30 minutes, and that's really

so that the moisturizer can settle in and doesn't dilute the sunscreen.

But I realize that this is quite, an arduous task.

You really become a project manager of skin, don't

you, when you're a parent?

Um, but What about treatments that could make kids more sensitive to the sun?

So most Eczema treatments won't make you more sensitive to sunlight.

There are some agents when there might be specific sun exposure recommendations.

So for instance, if people are using some of the topical immunomodulators like ta-

tacrolimus or pimecrolimus, … you're not supposed to a- apply those and

then go out in the sun, so then you might have to be using them nighttime.

Occasionally, even other medications like methotrexate can cause photosensitivity.

in general, if people are taking, medication that suppress the body's

immune system, take extra care in the sun.

But that's more the general immune suppressing treatments rather than the TH2

agents targeting the specific cytokines involved in eczema, so like Dupixent.

Yeah.

So as far as we know, sunlight sensitivity is not a commonly reported

problem with these newer biologicals.

But some of the older ones like methotrexate that were immune suppressing,

they could be more of a concern.

Yeah, that's right.

And so we know of no relationship between topical

steroids, and sun exposure.

Nope.

Okay, Let's have a chat about your research now, which

is photoaggravated dermatitis.

I have to admit, I didn't even know that it was a thing.

So can you explain what happens with UV light when it hits

eczema skin, and what's going on?

Of course.

We know from people having phototherapy, that you can get beneficial effects

of sunlight on the immune system and the barrier function of the skin.

But in some situations, sunlight exposure can be harmful.

And I'm particularly interested in this subgroup who seem to have a type of eczema

that's made worse by sunlight exposure.

We call this photoaggravated atopic dermatitis, or sometimes

photoaggravated eczema.

on these people, ultraviolet light, just everyday normal amounts of sun, which are

sub-sunburn doses even on normal-appearing skin can cause changes to the immune cells

and the barrier proteins in the skin.

With repeated low dose exposure , they would develop

changes which looked like eczema.

It can present as eczema that definitely gets worse after sun sunlight exposure

and there can sometimes be a bit of a gap between that exposure and the eczema

flaring, from a few hours to a few days.

Sometimes we'll see a pattern which is what we call photo distributed eczema,

and that just means the eczema is on the exposed areas, so the face, neck, arms,

hands, and the chest where their eczema tends to be worse in spring and summer.

And then sometimes people started phototherapy treatment

and, it worsens their eczema.

Right.

The commonest sunlight sensitivity disorder is another

condition called polymorphic light eruption, or sometimes people call

it prickly heat, and that can coexist with atopic dermatitis as well.

It often presents as itchy bumps that might be one or two days into the holiday.

But generally, it will go back to normal without going dry and

scaly or behaving like eczema.

Is that what I would know as, heat rash?

Slightly different.

So in heat rash, you can get it on covered sites as well, and it's

more to do with the sweat glands, whereas polymorphic light eruption

would be more on exposed sites.

That can be a helpful way to tell the difference.

But people do call it prickly heat because it often occurs when it's

hot, but it's a misnomer really because it's UV that's the trigger.

Right.

And do you see photo-aggravated atopic dermatitis in kids?

Yeah, we do.

it can present at any age, patients who were referred to our unit, were

from age five up to age in the 80s.

The peak was around 37 years.

Most of the time people developed it over time.

So perhaps in the same way that people develop photocontact allergies,

they develop allergy to sunlight.

And we're doing research at the moment find out how

common a problem it really is.

Okay.

And how will a parent be able to tell it apart, from heat or a sweat trigger?

And what should they do if, if they think it's a problem?

Yeah, it's challenging.

Keeping a diary can be really helpful of flares and thinking about the We

find photographs can be - extremely helpful when we see patients.

But thinking about the timing of flares, how much sunlight exposure

does it take to cause a flare?

How long does it last for?

thinking about response to sunscreen, does it only occur on exposed sites,

or can it be on covered sites?

And that can help to differentiate these other conditions that we've spoken about.

Sure.

So if you suspect that's the case, I would recommend

discussing it with your healthcare provider and dermatologist and

maybe looking into specialists who might have that expertise because

further testing could be appropriate.

Yeah, definitely.

Okay, if you're on a beach holiday with your eczema child, what would

your practical sun strategy be?

Yeah, really important.

I would focus on physical methods of UV protecting clothes , broad-brimmed

hats, sunglasses, avoiding the peak times of UV exposure, seeking shade.

you can get quite helpful UV protecting tents and parasols.

Remember on the beach, you can get quite a reflection off the sand, too.

Finding a really good sunscreen, applying it in sufficient quantities,

and reapplying it every couple of hours ideally or after getting wet, and also

not to forget about the usual eczema treatments just because you're on holiday.

And depending on whether your child's eczema improves or worsens

with sunlight exposure might affect how you behave on the beach.

But those would be the key points to think about really.

Thank you for explaining to us a, all about how we work with

sun exposure, and, sunscreens, and what to do if we think we have a

complication like photoaggravated atopic dermatitis . I hope this gives parents

some direction and feel more confident about the decisions they have to make.

Thanks so much