Emily Oster

9 min Read Emily Oster

Emily Oster

Kids and Masks

Emily Oster

9 min Read

The approval of vaccines for 5- to 11-year-old kids last week left a lot of parents (including this one; both kids had a first dose last Thursday) very relieved. It’s also given more attention to the ongoing conversation about when it makes sense to dial down some of the other COVID mitigation strategies — notably, masks. In recent weeks, a number of articles (here, here, here) have been written about the need to articulate “off-ramps” for masking in schools. These pieces recognize that while in-school masking provides some protection, with lower case rates and vaccines for kids and adults widely available, there will be a time to remove this layer. It goes without saying that the discussion is very fraught and generates a lot of anger.

A number of pieces have also been written about the evidence of the protective value of masks in schools. Not everyone agrees on that topic. But today I want to look at what we know about the other side of the coin, which is actually the question I get most frequently from parents: Are  there any downsides to mask wearing for kids in school or child care?

This feels important to consider, since it influences how we think about changes in masking policy. Here’s a simple thought experiment. Say that, instead of face masks, you protected against COVID-19 by wearing a friendship bracelet. Even still, some people would object to forcing children to wear one, claiming it infringed on freedom of expression, but most people would be willing to continue the practice as long as we believed it had some protective effect. On the other hand, imagine that the protection required kids to wear a blindfold at school. Again, some people would argue for continuing this indefinitely, at least until we reached “zero-COVID,” but most people would say that we’d need to be convinced of significant value to continue it.

All this is to say that as we contemplate off-ramps, or a move to “mask-optional” approaches in schools, the question of whether there are downsides to masks and, if so, how large they are matters. We will — and should — think about it differently depending on whether masks are more like friendship bracelets or more like blindfolds.

Interruption to say: By and large, kids have adapted extremely well to masks. They are able to wear them, and they don’t complain (much). Which is all great! But it doesn’t necessarily mean there are not some possible downsides.

When people discuss possible concerns with masks for kids, there are a few key issues that are raised:

  • Interference with breathing/respiratory health
  • Interference with social development (ability to read emotions and interact with friends)
  • Interference with intellectual development (learning to speak, learning to read, learning in general)
  • Concerns about students with disabilities

A TL;DR is that answering most of these questions precisely is extremely difficult or impossible. But by triangulating across different pieces of data, we can start to get a picture.

Respiratory function

In June, JAMA Pediatrics published a study in which the authors suggested that face masks cause children to inhale dangerous levels of carbon dioxide. This was based on laboratory measurements, and it really scared parents. Without going into details, the most important thing you should know is that the study was retracted. The calculations ignored some basic understanding of how breathing works. In fact, at least one other study (not retracted!) evaluated respiratory function in infants and young children while wearing masks and did not find any evidence of impacts.

There’s other work focused on the theory of whether face masking would impact respiratory function, even during exercise, that does not suggest impacts. The bottom line is that while you can certainly find anecdotal evidence of people claiming their child cannot breathe wearing a mask, this isn’t a claim that is well supported in the data.

Social and intellectual development

I’m going to lump these together, because the type of evidence we bring to bear on them is roughly the same.

Stepping back: the concerns here stem from the observation that the bottom half of the face is important for reading emotions, learning to speak, and learning to read. The theory behind this is compelling.

In the study of socioemotional development, the idea of facial expressions conveying emotions goes back to Charles Darwin (in one of his lesser-known books, The Expression of the Emotions in Man and Animals). As adults, it should be obvious from our own experience that we use facial expressions to understand the emotions of others.

This is a skill that develops over childhood (see, e.g., this paper on how kids get better at reading emotions from faces between the ages of 3 and 11). Kids differ in the speed at which they develop this ability; there is literature on how children’s reading of facial expressions correlates with their social skills. This starts early: Infants respond to faces, rapidly learning to distinguish between happy, sad, and other emotions, and can distinguish their mom’s face from others within a short period.

There is also a potential role for facial expressions in language development. Watching how mouths move is part of learning to speak (see, e.g., this paper). And when kids need help with speech issues, being able to observe the movement of their mouth and the mouths of others in pronouncing letters is crucial.

A final argument relates to hearing. There is direct evidence that masks make it difficult to hear the speaker, and that this may be exacerbated for kids in loud classrooms. It stands to some logic that if you are trying to teach a young child to read — or, really, do anything — it is valuable for them to be able to hear you. And social interactions are better if kids can hear each other and be heard by teachers.

Putting all this together, it is reasonable to think that some aspects of learning or social skills may be impacted by masks, and indeed others have argued this. But this isn’t quite the same as direct evidence that masking matters, and it doesn’t tell us about magnitudes. Maybe seeing half a face is almost as good as a whole face. The impacts of hearing on learning may be small.

Large-scale evidence on the particular question of masking in schools and development is lacking and is unlikely to ever appear. One could imagine exploiting differences across schools in mask policies to look at differences in learning outcomes, but you would rapidly realize in doing so that too many other things vary across these schools. There will never be anything convincingly causal.

What we can see is a bit of lab-based evidence on masks directly, especially on emotion-reading. There is, for example, this paper showing that children performed worse on a face-perception test when masks were involved versus without. There’s also this paper — co-authored by a researcher and a 9-year-old — which showed that children had trouble reading emotions from masked faces. Or this one, which showed that masks reduced kids’ ability to read emotions from pictures (though notably, not more than sunglasses).

This type of in-lab analysis for studying language development or learning evolution is less feasible, and there is therefore little we can say directly.

In the end, what we arrive at is a lot of theoretical reasons to think that masking could be somewhat detrimental to social learning and intellectual progress, with the evidence for the former being somewhat stronger. It is nearly impossible to be precise about magnitudes.

Students with disabilities

For students with disabilities — especially students who are deaf, or those with autism, for whom reading emotions is already more challenging — masks may be a particular barrier. There is some direct evidence among children with hearing impairment of masks impacting their word understanding.

A challenge is that these students are also, in some cases, at higher risk for COVID-19. There is a balance, then, between risk and benefit.

Summing up

It remains extremely difficult to make any concrete statement about possible risks or downsides of masks in kids. Perhaps the strongest evidence is on impacts on emotion-reading, but even there we have to ask: How much does it matter in practice? If kids are unmasked at home and when out at recess, is it a big deal to wear a mask while learning to subtract?

We expect variation in impacts across children. Those who are slightly hearing-impaired, or have more trouble paying attention, may be more affected by the muffled nature of voices through masks. Those kids who struggle more to read emotions may benefit more from getting “whole-face” information and, on the flip side, struggle more with masks.

None of this is intended to scare parents. Kids are resilient, kind of amazingly so. If your child is in school with a mask, you shouldn’t panic — and far, far better to be in person at school with masks than at home without.

So this isn’t a moment to be scared about yet another thing. But what seems quite clear to me in reflecting on this is that masks are not a friendship bracelet. The effects may be small, or mixed across kids, but in the absence of a disease risk, we would not have children mask at school or child care. And these effects are likely larger for younger kids. Which means that there are strong reasons to consider when we will feel the COVID risks are such that we can remove masks, probably even before the youngest kids are vaccine-eligible. Which, basically, means we need to design off-ramps.

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SLEEP DATA 💤 PART 2: Let’s talk about naps. Comment “Link” for an article on what we learned about daytime sleep!

The first three months of life are a chaotic combination of irregular napping, many naps, and a few brave or lucky souls who appear to have already arrived at a two-to-three nap schedule. Over the next few months, the naps consolidate to three and then to two. By the 10-to-12-month period, a very large share of kids are napping a consistent two naps per day. Over the period between 12 and 18 months, this shifts toward one nap. And then sometime in the range of 3 to 5 years, naps are dropped. What I think is perhaps most useful about this graph is it gives a lot of color to the average napping ages that we often hear. 

Note: Survey data came from the ParentData audience and users of the Nanit sleep monitor system. Both audiences skew higher-education and higher-income than the average, and mostly have younger children. The final sample is 14,919 children. For more insights on our respondents, read the full article.

SLEEP DATA 💤 PART 2: Let’s talk about naps. Comment “Link” for an article on what we learned about daytime sleep!

The first three months of life are a chaotic combination of irregular napping, many naps, and a few brave or lucky souls who appear to have already arrived at a two-to-three nap schedule. Over the next few months, the naps consolidate to three and then to two. By the 10-to-12-month period, a very large share of kids are napping a consistent two naps per day. Over the period between 12 and 18 months, this shifts toward one nap. And then sometime in the range of 3 to 5 years, naps are dropped. What I think is perhaps most useful about this graph is it gives a lot of color to the average napping ages that we often hear.

Note: Survey data came from the ParentData audience and users of the Nanit sleep monitor system. Both audiences skew higher-education and higher-income than the average, and mostly have younger children. The final sample is 14,919 children. For more insights on our respondents, read the full article.
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Happy Father’s Day to the Fathers and Father figures in our ParentData community! 

Tag a Dad who this holiday may be tricky for. We’re sending you love. 💛

Happy Father’s Day to the Fathers and Father figures in our ParentData community!

Tag a Dad who this holiday may be tricky for. We’re sending you love. 💛
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#parentdata #postpartum #postpartumdepression #paternalmentalhealth #newparents #emilyoster

“Whilst googling things like ‘new dad sad’ and ‘why am I crying new dad,’ I came across an article written by a doctor who had trouble connecting with his second child. I read the symptoms and felt an odd sense of relief.” Today we’re bringing back an essay by Kevin Maguire of @newfatherhood about his experience with paternal postpartum depression. We need to demystify these issues in order to change things for the better. Comment “Link” for a DM to read his full essay.

#parentdata #postpartum #postpartumdepression #paternalmentalhealth #newparents #emilyoster
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Head to the newsletter for more and stay tuned for part two next week on naps! 🌙

#parentdata #emilyoster #childsleep #babysleep #parentingcommunity

SLEEP DATA 💤 We asked you all about your kids’ sleep—and got nearly 15,000 survey responses to better understand kids’ sleep patterns. Comment “Link” for an article that breaks down our findings!

This graph shows sleeping location by age. You’ll notice that for the first three months, most kids are in their own sleeping location in a parent’s room. Then, over the first year, this switches toward their own room. As kids age, sharing a room with a sibling becomes more common.

Head to the newsletter for more and stay tuned for part two next week on naps! 🌙

#parentdata #emilyoster #childsleep #babysleep #parentingcommunity
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Weekends are good for extra cups of ☕️ and listening to podcasts. I asked our team how they pod—most people said on walks or during chores. What about you?

Comment “Link” to subscribe to ParentData with Emily Oster, joined by some excellent guests.

#parentdata #parentdatapodcast #parentingpodcast #parentingtips #emilyoster

Weekends are good for extra cups of ☕️ and listening to podcasts. I asked our team how they pod—most people said on walks or during chores. What about you?

Comment “Link” to subscribe to ParentData with Emily Oster, joined by some excellent guests.

#parentdata #parentdatapodcast #parentingpodcast #parentingtips #emilyoster
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Humility. That’s why. That’s the whole reason.

#emilyoster #secondbaby #parentingjokes #parentinghumor

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Prevention is key! I suggest:
⭐ Regular tick checks
⭐ Using bug sprays with DEET 
⭐ Wearing long sleeves and pants in the woods

Some parents worry about DEET, but repellants with up to 30% DEET are recommended by both the CDC and AAP. The data says you’re in the clear, so go for it. Enjoy your summer!

#parentdata #emilyoster #tickseason #bugbites #bugspray

Bug season is upon us. Besides annoyance, this can bring up safety concerns, particularly with ticks. They are carriers of diseases, most notably Lyme disease. So what’s the best course of action?

Prevention is key! I suggest:
⭐ Regular tick checks
⭐ Using bug sprays with DEET
⭐ Wearing long sleeves and pants in the woods

Some parents worry about DEET, but repellants with up to 30% DEET are recommended by both the CDC and AAP. The data says you’re in the clear, so go for it. Enjoy your summer!

#parentdata #emilyoster #tickseason #bugbites #bugspray
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What an amazing group of women, and an honor to speak at the #MomsFirstSummit debunking parenting myths.

What are some pregnancy rules you chose to bend after being empowered by data?

#emilyoster #parentdata #pregnancyproblems #pregnancymyths
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👉Comment “Link” for a DM to an article that summarizes all of the best potty training advice we collected. 

Remember, you are not alone in the potty training struggle! It can be incredibly challenging, so please give yourself some grace.

#emilyoster #parentdata #pottytraining #pottytrainingtips #toddlertips

Looking for Memorial Day Weekend plans? Might be the perfect time to give potty training a shot. Potty training is notoriously difficult, and we unfortunately don’t have a lot of evidence-based guidance on what works best. So I asked the ParentData community to fill out a survey and share their knowledge — about 6,000 people responded.

👉Comment “Link” for a DM to an article that summarizes all of the best potty training advice we collected.

Remember, you are not alone in the potty training struggle! It can be incredibly challenging, so please give yourself some grace.

#emilyoster #parentdata #pottytraining #pottytrainingtips #toddlertips
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We’re hiring an Associate Editor at ParentData! More details at my link in bio. Please share with the great writers and data-loving people in your network. 📊💻

We’re hiring an Associate Editor at ParentData! More details at my link in bio. Please share with the great writers and data-loving people in your network. 📊💻 ...

Do you brand things a certain way to get your kid to accept it? Like calling carrots “rabbit popsicles”? Or telling them to put on their “super speed socks” in the morning? Share your rebrands in the comments below! You never know who you might be helping out 👇

#emilyoster #funnytweets #relatabletweets #parentingjokes #kidssaythedarndestthings

Do you brand things a certain way to get your kid to accept it? Like calling carrots “rabbit popsicles”? Or telling them to put on their “super speed socks” in the morning? Share your rebrands in the comments below! You never know who you might be helping out 👇

#emilyoster #funnytweets #relatabletweets #parentingjokes #kidssaythedarndestthings
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Have you ever panic-googled a parenting question when everyone else is asleep? If so, you’re not alone. 

Today is the first episode of a new biweekly series on my podcast: Late-Night Panic Google. On these mini-episodes, you’ll hear from some familiar names about the questions keeping them up at night, and how data can help. First up: @claireholt!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #emilyoster #claireholt #parentingstruggles #parentingtips #latenightpanicgoogle

Have you ever panic-googled a parenting question when everyone else is asleep? If so, you’re not alone.

Today is the first episode of a new biweekly series on my podcast: Late-Night Panic Google. On these mini-episodes, you’ll hear from some familiar names about the questions keeping them up at night, and how data can help. First up: @claireholt!

Listen and subscribe to ParentData with Emily Oster in your favorite podcast app 🎧

#parentdata #emilyoster #claireholt #parentingstruggles #parentingtips #latenightpanicgoogle
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Sun safety is a must for all ages, especially babies! Here are my tips for keeping your littlest ones protected in the sunshine:
☀️ Most importantly, limit their time out in hot weather. (They get hotter than you do!)
☀️ Keep them in the shade as much as possible when you’re out.
☀️ Long-sleeve but lightweight clothing is your friend, especially on the beach, where even in the shade you can get sunlight reflecting off different surfaces.
☀️ If you want to add a little sunscreen on their hands and feet? Go for it! But be mindful as baby skin tends to more prone to irritation.

Comment “Link” for a DM to an article on the data around sun and heat exposure for babies.

#sunsafety #babysunscreen #babyhealth #parentdata #emilyoster

Sun safety is a must for all ages, especially babies! Here are my tips for keeping your littlest ones protected in the sunshine:
☀️ Most importantly, limit their time out in hot weather. (They get hotter than you do!)
☀️ Keep them in the shade as much as possible when you’re out.
☀️ Long-sleeve but lightweight clothing is your friend, especially on the beach, where even in the shade you can get sunlight reflecting off different surfaces.
☀️ If you want to add a little sunscreen on their hands and feet? Go for it! But be mindful as baby skin tends to more prone to irritation.

Comment “Link” for a DM to an article on the data around sun and heat exposure for babies.

#sunsafety #babysunscreen #babyhealth #parentdata #emilyoster
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