The Great Indoors

Roman Mars:
This is 99% Invisible. I’m Roman Mars.

Roman Mars:
This winter is going to be brutal. I mean, it is just going to suck, and if you’re like me, you’ve been spending a lot of time at home since March. And it’s starting to feel a little claustrophobic, maybe more than a little, a lot claustrophobic. Though if you think about it, were you actually going outside all that much before the pandemic?

Emily Anthes:
Modern humans are essentially an indoor species. We spend roughly 90% of our time indoors, and that was before the pandemic hit.

Roman Mars:
This is author Emily Anthes.

Emily Anthes:
And my book is “The Great Indoors: The Surprising Science of How Buildings Shape Our Behavior, Health, and Happiness.”

Roman Mars:
Emily’s book looks at how our indoor spaces are actually a giant mystery. There is so much we don’t know, like there are thousands of bacteria and microbes living inside our homes, and we haven’t really studied them.

Emily Anthes:
So, we spend so much time in these places that we don’t think of them as exotic or interesting. If you’re an ecologist, you want to go to the Amazon or to Antarctica, and maybe you’re not that interested in the ecosystems that are in our homes, so there’s all this complexity that we’re just scratching the surface of.

Roman Mars:
Today, as we head into a winter lockdown, we’ll talk to Emily about how sunlight and ventilation, and the tiny, creepy-crawly things in our homes, can influence our health and wellbeing, and how we can use design to make our indoor spaces so much better.

[MUSIC FADES]

Roman Mars:
So let’s talk about these microbes, which is the creepy-crawliest part of your book. We haven’t studied the bacteria and microbes that live inside our homes all that much. What is living there, how bad is it? What kind of a forest am I living in?

Emily Anthes:
Yeah, well so one study to start to quantify this comes from North Carolina, and they studied several dozen homes there, and they found that on average, the homes housed 2,000 different types of microbes. So that is mostly bacteria, but it does also include some fungi, and it’s actually more diverse inside our homes than outside them, and that’s because the microbes are coming from a couple of different sources. So the vast majority of bacteria in our homes, at least, are coming from us. So we now know that our bodies are covered with and full of microbes, and when we move around a space, we are shedding them constantly, so that’s a large part of what’s in our homes.

Emily Anthes:
But then there are also species that live in our homes. Maybe they’re growing in the plumbing, or they’re growing in the insulation. One of my favorite home environments is the extreme environment of the dishwasher or the washing machine. So if you think about what’s happening in there, it’s mostly bone dry, which microbes don’t like, but then every once in a while it gets completely saturated with water, it gets real hot, you put detergent in it, and it turns out that’s selected for these strange kinds of black yeasts that don’t look anything like any other yeasts scientists have found anywhere, so it seems to be this unique ecosystem. And then finally, we have the microbes that are drifting in from outdoors, so things that live in the soil or in water, and it attaches to us or comes in through an open door or window. So you have all these different sources of microbes.

Roman Mars:
You talk in the book about another kind of strange Petri dish inside your apartment that you were interested in — you sent in your shower head to be studied. What did they find in your shower head?

Emily Anthes:
Yeah, so shower heads are also interesting environments because they are also these sorts of extreme environments which are dry the vast majority of the time, but then all of a sudden get flooded, and some of what they found in my shower head was not very surprising. So there was lots of bacteria that typically lives in tap water and in soil, and no one was surprised to see that, but there were other creatures that were still pretty mysterious. So my favorite is something that scientists have not studied very much at all yet, it doesn’t even have a real scientific name, it just goes by the very poetic RB41 right now, and two other places it’s been documented are dog noses and paleolithic cave paintings. And so we have this bacteria that we don’t know really what it does or why it’s in my showerhead, and what my showerhead might have in common with these other environments, it’s all still kind of a mystery.

Roman Mars:
So do these microbes in our homes, do they make us sick, or do they make us healthier because they… We build up immunities to these things and other things because of them? What is this overall effect of them on us?

Emily Anthes:
As far as we know, the vast majority of these microbes are innocuous. They don’t seem to affect us one way or the other. And a lot of them are coming from us to begin with, so they’re already microbes that are living in and on our bodies. but there are some on both sides of the spectrum. So there are absolutely some pathogens, which I know is something we’re thinking a lot about right now, some of us may have coronavirus in our homes. We know that certain kinds of molds can trigger allergies and asthma, there are certain types of bacteria that live in plumbing that can cause lung infections.

Emily Anthes:
But that’s a small fraction of what’s in our homes, and there’s good reason to think that some of these microbes are actually good for us. So there’s a growing body of literature that suggests that kids who grow up surrounded by a rich assortment of microbes actually are less likely to develop allergies and asthma and autoimmune disease, and the theory is because exposure to all these microbes early in life essentially helps train your immune system so it doesn’t overreact later on.

Roman Mars:
Speaking of the microbes that are kind of good for us, you mentioned that homes with dogs have healthier microbiomes, tell me about that?

Emily Anthes:
Yeah, this is satisfying to me as a long-time dog owner and lover, but dogs introduce a lot of new microbes into a home. So they’re the microbes that actually live in and on the dog, but then most dogs are going in and outside, and so they’re tracking in soil microbes, stuff from grass, microbes from whatever they’ve eaten at the dog park, and for whatever reason, some of these microbes seem to be associated with our immune health, so there are studies that show that kids that grow up with dogs have a lower propensity for developing asthma and allergies and some of those conditions. So it’s a bit tricky to isolate which microbes those are, that’s something that science has not been able to do very well yet, but something about the community of microbes that dogs are introducing into homes seems to be protective.

Roman Mars:
And we’ve introduced a lot of products in the last few years that are anti-microbial, including window cleaners and hand soaps and floor cleaners, all kinds of stuff. Have they made our homes healthier?

Emily Anthes:
I think it’s a little too early to answer that definitively, but there are some worrisome signs that maybe they’re having a negative effect on our home microbiome. So there is some research that suggests that the more you use anti-microbial chemicals in your home, like cleansers, the more that the bacteria there are evolving resistance to those chemicals, so that’s one potentially negative ramification, is that using all these cleansers could be helping to drive the evolution of antibiotic-resistant bacteria. The other potential problem is that cleaning with something like that is sort of a crop duster approach, and you might be wiping out the microbes that are good for us along with anything dangerous, so I think there’s reason to be pretty cautious using these products.

Roman Mars:
In terms of indoor health, the biggest factor might be air quality, and it’s another factor that we don’t know much about, so how bad is the air that we’re breathing indoors?

Emily Anthes:
Yeah, so that’s one of the things that we’re still trying to get a better handle on. I mean, one trend that does seem apparent is at least here in the U.S., in most places, outdoor air has gotten much better over the course of the 20th century, and partly that’s because of regulation. We have brought down emissions. But one result of that is that for many people, their primary source of exposure to air pollution happens indoors now. So that comes from all sorts of sources, some of it is just the products we fill our homes with, so things like our sofa, our flooring, all of our personal care products just release all of these chemicals into the air. But then our own behavior and activities inside our homes can also generate pollution, so cooking and cleaning are the big ones that are known to generate these big spikes in air pollution.

Roman Mars:
Yeah, air quality is an understudied problem, but it’s not a new problem. You have this whole chapter on ventilation in health, and you talk about how Florence Nightingale used to advocate for open windows in hospitals, and that was back in the 19th century, and I was thinking about this the last time I was in the hospital, and it was not open at all, there was no fresh air, it was totally sealed up. Can you talk about the back and forth of how we see ventilation?

Emily Anthes:
Yeah, so there’s been an interesting history here, and hospitals several centuries ago were not a place you would want to go if you were sick. If you could afford it, you would get a doctor to come to you, and so hospitals were really… They were dirty, they were unhygienic, they were overcrowded. In some places, patients even shared not just rooms, but beds, which you can imagine is not great for the spread of infectious disease. And Florence Nightingale was one of these reformers who came along and advocated better sanitation, like basic stuff that now we sort of take for granted, like actually adequate drainage in a hospital room so fluids weren’t just sitting there, and opening windows, and daylight. And one of the interesting things was that she didn’t really understand the mechanism of infectious disease.

Roman Mars:
Right.

Emily Anthes:
I mean, nobody did at that time. Germ theory was not a widely-accepted disease mechanism. But she intuited and she observed that patients did better when she let more fresh air in and let more light in, and that was a trend in hospital design for a short period of time, towards the end of the 19th century especially. But then when germ theory did become more widely accepted and we had antisepsis and anti-microbial chemicals, and technology improved, we sort of moved in the other direction, and hospitals began to close themselves up and rely on chemicals for disinfection, and technology, and they became these hermetically-sealed spaces. And I think one thing we have learned is that we have gone too far in that direction, and we need to figure out ways to create more permeability between our indoor and our outdoor spaces.

Roman Mars:
I mean, right now in this current health crisis, we’re learning about the importance of ventilation all over again, what do you make of that?

Emily Anthes:
Even before the pandemic hit, I think there was a slow-growing realization that indoor air quality was important and that ventilation was important, but the pandemic has absolutely accelerated that trend and made a lot of people think a lot more about air quality and ventilation than I bet they ever had before, and we know that increasing ventilation and bringing in more fresh air from outside, and changing the air over more often, can all really reduce the spread of infectious disease indoors.

Emily Anthes:
I think some of the improvements that we are thinking about making now – and here I’m thinking particularly about what’s happening in schools, where school ventilation systems are being overhauled and improved – will have a lot of dividends even when the pandemic is over. We know that improving ventilation can improve our cognitive performance, and could improve student learning in schools, and schools have been sort of criminally under-ventilated in America for a long time. And so this is not how anyone would have wanted schools to be overhauling their ventilation systems, but it’s long overdue, and I’m hoping that the pandemic will lead to improvements in that regard that pay off for a long time.

Roman Mars:
Is the solution for making a healthier indoor space is just to make it more like the outdoors? Is that what we’re learning?

Emily Anthes:
Well, that is one of the ironies of what I learned when researching the book that I… I was not necessarily expecting that. I talk about how I’m an indoorsy person, and I wasn’t necessarily expecting one of the takeaway lessons to be “to create a healthy indoor space, make it more like the outdoors,” but that does seem to be a lesson. So it applies to fresh air, but bringing in sunlight, bringing in elements of nature, bringing in outdoor microbes, all of those things seem to have a variety of health benefits.

Roman Mars:
More nature. It seems like it’s connected to learning about dog noses and cave paintings, it feels like we keep forgetting that we’re actually animals, and we have to keep learning that.

Emily Anthes:
Yeah, absolutely, and we now know that there are ecosystems in our homes, but we are also part of those ecosystems, they’re not systems that exist separate from us, we affect the microbes that colonize our homes, and they affect us back, and the same thing with insects and rodents, and all sorts of other stuff that might be living in our homes.

Roman Mars:
Right now, designers are coming up with new ways to combat the bad air and the bad lighting, and all the unhealthy parts of life indoors, and while those design solutions are really promising, sometimes they have unintended consequences. So, Emily, you talk about this Bronx housing development that was designed to make its residents more healthy, what did they do?

Emily Anthes:
This is a housing development known as Arbor House, and it was designed with the principles of what has become known as active design, and the idea behind active design is can we subtly encourage people to get more physical activity just as part of their everyday lives, so without telling them to go to the gym three days a week? And it’s based on research that shows that even just a modest increase in physical activity, so you know, climbing three flights of stairs a day, can have long-term benefits for our health. So Arbor House is an eight-story affordable housing complex in the Bronx, and it opened in 2013, and it has all sorts of features that are designed to make physical activity appealing, fun, and sort of part of the default behavior. So the most obvious example has to do with stairs and elevators. If you think about any high-rise building you go into that has elevators, normally they’re the first thing you see, they’re gleaming, they’re prominent in the lobby, and if you can find the stairs at all, they’re hidden behind a heavy fire door, and it’s flickering fluorescent lights, and it’s just not appealing.

Emily Anthes:
But the principles of active design, and which were used here at Arbor House, really try to flip the script. So how can we make the stairs more appealing and more fun, and the default behavior? So they’ve done that in a couple of ways here. There are motivational signs by the elevators that encourage residents to take the stairs instead, which a number of studies suggest is effective, but then there are also things like there’s art hanging in the stairwells, and there’s music playing in the stairwells, which residents in focus groups have said they and their kids actually liked so much that it made them take the stairs more often. And there are more subtle things too, like the stairs are wide and they’re well-lit, and they’re safe, which isn’t always true in some of these affordable housing complexes. There were residents who said they didn’t feel safe taking the stairs at their old apartment buildings because it was dark and you couldn’t see who else was in there, but here it’s open and visible and prominent. That’s one set of strategies that designers can use to encourage more physical activity. There are others as well.

Roman Mars:
Yeah. And are there some drawbacks to pushing people to use stairs? It seems like you can make the stairs more appealing, but you could also make the elevators less convenient, which doesn’t serve everyone in the population.

Emily Anthes:
Yeah, that’s a really good point, and that is the big drawback I think about when it comes to certain strategies for active design, and in fact, Arbor House has employed one strategy that I don’t think is great from an accessibility standpoint, which is to deliberately slow down the elevators. That, as you can imagine, is an incredible inconvenience for people who can’t or don’t want to use the stairs. So I do think that some of these strategies are much better choices from an accessibility standpoint, so as you can imagine, adding art and music to a stairwell is not going to inconvenience someone who can’t take the stairs, but slowing the elevators down does. So can things like skip-stop elevators, which only open every other floor, which is another strategy, so I think designers need to be really careful about which of these techniques they employ.

Roman Mars:
Emily Anthes will tell us about one incredibly easy trick to make our homes healthier, after this.

[BREAK]

Roman Mars:
So I want to talk a little bit about other sort of design solutions for making the inside healthier. A lot of designers are thinking about smart homes as a way of making the indoors healthier with sensors that open the windows if there’s bad air quality or they call 911 automatically if someone falls. A lot of this stuff, it feels very designy. It feels very utopian. I have to admit, I find it kind of dystopian. How do you feel about smart homes and their promise?

Emily Anthes:
I think it is both. And there are, you know… It can be utopian and dystopian and in fact, the same devices and technology can be both depending on how it’s used. I mean, I think there is enormous potential here, especially when you look at some of the sectors where it’s being applied first. I write a lot about the senior care community and we don’t have a great system of senior care here in the U.S. And lots of seniors want to continue to live independently in their own homes. But often that’s difficult, especially if they’re living alone. And so I think there is potential there for technology to make that safer, whether that’s sensors built into the floor that can detect a fall or a smart oven sensor that can remind someone with dementia to turn off the oven. But there’s a lot of risk there, too. You know, privacy. Also, when you think about the senior care community, that raises even, I guess, stickier questions of consent. I talked to some researchers who said people’s middle-aged children are really excited to install these monitoring systems, but the seniors themselves were not necessarily always open to them. So there are a lot of dangers here, too.

Roman Mars:
Okay, so if people are listening to this and they’re in their homes, most likely 90% chance they’re in their home listening to this, what can they do to make their home healthier right now? Like, what would you tell someone to do to make their house a healthier place?

Emily Anthes:
One thing we haven’t talked about yet, which is probably my top recommendation for everyone, is nature. There is just an incredible body of research that demonstrates that exposure to nature has enormous and wide-ranging benefits from reducing stress and pain to boosting mood concentration, productivity, improving the immune system. I mean, almost, you name it, nature benefits it. And the interesting thing about it is that it doesn’t seem to have to be a particular kind of nature. So a lot of the original studies were done on views and they found that people who had views of natural landscapes recovered faster from surgery than those who didn’t. And so if you have views of natural landscapes, that’s great. But studies suggest that even something like bringing houseplants into your home has some of the same benefits and so does nature imagery. So putting photographs of natural landscapes up on your wall can help. And so, interestingly, do nature sounds so listening to birdsong or babbling brook or something over speakers over your headphones can have some of the same stress alleviating effects. So any way you can find to bring some element of greenery or the natural world into your living space, I highly recommend.

Roman Mars:
I like that you could play bird song and it would help you out. That’s brilliant.

Emily Anthes:
And actually, I believe there’s a study that even fake plants like plastic plants, like if you like houseplants, but you just really have a black thumb, you could maybe get some of the same stress relief from bringing in some faux greenery.

Roman Mars:
(Laughs) That’s amazing. That’s amazing.

Emily Anthes:
Yeah, well, the research suggests and most scientists think that this is a psychologically mediated effect and they explain it with what’s known as the Biophilia hypothesis, which is that because of how we evolved, sort of out in the rough and tumble of nature, we have this innate affinity for and attraction to nature. And so whether it’s an actual landscape out the window or a photo of a landscape on the wall, it sort of catches our attention. It engages us. It serves as a positive distraction, sort of taking our mind off of whatever might be stressing us out, our pain and the other benefits sort of follow from that psychological positive distraction.

Roman Mars:
So let’s talk a little bit about COVID and things that we might be able to continue on. So a lot of us have been thinking differently about the indoors because of COVID. What are some of the things you think might change about the design of our indoor spaces that we’re experimenting with now that we might keep when the pandemic is over?

Emily Anthes:
I think we might see people thinking more about flexibility and how we can design flexible spaces. You know, most directly related, you can think of hospitals and you’ve seen hospital capacity just swell. I have talked to health care designers who have said we want to think about how we can design hospitals that can suddenly treat many more patients if need be in the future. But even at the level of our home, we are suddenly having to carve out workspaces and classrooms in our homes, which we probably weren’t expecting. and so I think we will see an emphasis on creating homes and other buildings that have adaptive use or maybe flexible use of space, maybe partitions or movable room dividers. Things like that, I think will be helpful and in demand. And, you know, even if you’re building a house post-COVID, there could always be another pandemic or who knows what else, natural disasters, more uncertainty. And so I think the more we can create indoor spaces that we can quickly adapt for new uses, the better off will be.

Roman Mars:
Emily Anthes’s book is called “The Great Indoors: The Surprising Science of How Buildings Shape Our Behavior, Health, and Happiness.” It is so good. It’s a 99pi book through and through. You’re going to love it.

———

Roman Mars:
99% Invisible was produced this week by Chris Berube. Music by Sean Real. Our senior producer is Delaney Hall. Kurt Kohlstedt is the digital director. The rest of the team includes Emmet FitzGerald, Joe Rosenberg, Vivian Le, Christopher Johnson, Abby Madan, Katie Mingle, Sofia Klatzker, and me, Roman Mars. We are a project of 91.7 KLAW in San Francisco and produced on Radio Row, which lives at the far corners of North America right now, but it is centered in beautiful downtown Oakland, California.

You can tweet me @romanmars and the show @99piorg. We’re on Instagram and Reddit too. And right now you can take care of all of your holiday shopping right now by ordering multiple copies of the 99% Invisible City and 99pi.org/book. We have links to purchase it wherever you get your books, including signed editions, the audiobook, anywhere you want it, we can get it to you. That’s a 99pi.org/book. And for all your other 99pi needs, look no further than 99pi.org.