Watch the replay of this event held on January 19, 2022. (Transcript below.)

Sleep is critically important for health: If disrupted, it can literally make people sick, upping the risks for ills such as cardiovascular disease, cancer and depression. A good night’s sleep is a luxury for many, but poor people and members of racial and ethnic minorities are more likely than others to not get enough. Learn how slumber affects the body on a physiological level, and the implications for disease risk. What happens during normal sleep and when sleep is disrupted? What factors contribute to disparities in sleep health and how can they be remedied? And how can we all practice good sleep hygiene?

Watch the discussion and Q&A with two experts, and get your questions answered.


Carmela Alcántara, Columbia University

Dr. Carmela Alcántara is director of the Sleep, Mind, and Health Research Program at the Columbia School of Social Work and a faculty affiliate for the Social Intervention Group and the Columbia Population Research Center. Her research integrates psychology, public health, social work and medicine to understand how structural and social factors affect sleep and mental and cardiovascular health, particularly in racial/ethnic and immigrant communities. As a licensed clinical psychologist with training in public health and behavioral medicine, she is committed to translating her findings into interventions to reduce health disparities. Her work has been supported by the National Institute of Mental Health, the National Heart, Lung, and Blood Institute and the W.K. Kellogg Foundation.

 Michael R. Irwin headshot

Michael R. Irwin, UCLA Geffen School of Medicine

Dr. Michael R. Irwin is director of the Cousins Center for Psychoneuroimmunology at UCLA’s Semel Institute for Neuroscience, director of the Mindful Awareness Research Center and the M.D. Cousins Distinguished Professor of Psychiatry and Biobehavioral Sciences. He is an expert and research pioneer on the interaction between the immune and central nervous systems and the impact of sleep disturbances on the inflammatory signaling pathways that influence depression. His research integrates data from a broad range of studies and controlled trials that employ mind-body and behavioral approaches, and has been supported with awards from multiple institutes including the National Cancer Institute, National Heart, Lung, and Blood Institute, and the National Institute of Mental Health.


Rachel Ehrenberg headshot

Rachel Ehrenberg, Associate Editor, Knowable Magazine

Rachel has been covering science for nearly 20 years. She has a master’s degree in evolutionary biology from the University of Michigan and a graduate certification in science communication from the University of California, Santa Cruz. In 2013-2014, she was a Knight Science Journalism Fellow at MIT.


This event is part of Reset: The Science of Crisis & Recovery, an ongoing series of live events and science journalism exploring how the world is navigating the coronavirus pandemic, its consequences and the way forward. Reset is supported by a grant from the Alfred P. Sloan Foundation.

Knowable Magazine is a product of Annual Reviews, a nonprofit publisher dedicated to synthesizing and integrating knowledge for the progress of science and the benefit of society. Major funding for Knowable comes from the Gordon and Betty Moore Foundation.


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Rachel Ehrenberg: Good morning, or good afternoon or evening. I’m Rachel Ehrenberg. I’m an editor at Knowable Magazine from Annual Reviews, and I’m happy to welcome you to the 14th conversation in our online event series. Today, we’re going to be talking about sleep. And I’m sure you’ve all heard that getting a good night’s sleep is important, but really that’s an understatement. Sleep turns out to be critically important for good health. When it’s disrupted, it can literally make people sick. It ups the risk for all sorts of ills, from cardiovascular disease to cancer to depression and more.

And while a good night’s sleep is a luxury for many, poor people and members of racial and ethnic minorities are more likely than white people to not get enough sleep. Sleep disorders like obstructive sleep apnea are more common in people of color. That puts them at risk for a slew of other health problems. Shift work and living in low-income neighborhoods are also risk factors for poor sleep.

So today we’re going to talk about how sleep affects the body, what happens during normal sleep, what happens when sleep is disrupted, and what factors contribute to these disparities in sleep health and how they might be remedied. And we’re also just going to talk about how we can all practice good sleep hygiene for our better health.

I’m thrilled that we have two great people with us today to share their expertise and perspectives, and to answer your questions. I want to welcome Dr. Carmela Alcántara, director of the Sleep, Mind, and Health Research Program at the Columbia School of Social Work in New York. Her research integrates psychology, public health, social work and medicine to understand how structural and social factors affect sleep and mental and cardiovascular health, particularly in racial, ethnic and immigrant communities.

I also want to welcome Dr. Michael Irwin. He’s the Norman Cousins Professor of Psychiatry and Biobehavioral Science at the UCLA Geffen School of Medicine, and he directs the Cousins Center for Psychoneuroimmunology at UCLA‘s Semel Institute for Neuroscience. He‘s done a lot of work investigating the effect of sleep disturbance on the molecular and cellular inflammatory signaling pathways in the body, which we‘ll hear more about.

Thank you both very much for being here. I’m really looking forward to the conversation.

I want to just start with some basics. And, Michael, if we can begin with you: What is sleep, and briefly, how is it studied?

Michael Irwin: So sleep is a behavioral state. It occurs mainly during the night. We know that it can be measured by a variety of different approaches. The diagnostic approach that we use to evaluate sleep disturbance is actually asking people how well they slept and whether they woke up during the night and whether they woke up repeatedly during the night and whether they could go back to sleep. So people actually have a pretty good sense of how well they are sleeping and whether they’re waking up feeling rested. So that’s a basic level — a questionnaire that asks about their sleep.

We can also ask about — use a sleep diary — so they can actually record the number of times that they’ve awaken during the night and how long it took them to go back to sleep and there’s an estimate. We can provide objective evidence of that kind of sleep during the day, as well as during the night, as well as during the day, by using an actigraph, which is like a very small wristwatch that can evaluate how many times you move throughout the night and to what degree that you also move or don’t move during the day. And there’s thresholds of movement that we can estimate whether a person’s actually sleeping or awake in their bed.

And finally, we can use a polysomnography, which is providing or placing electrodes on the brain, on the scalp, excuse me, that records signals from the brain about the brain waves and the changes in the activities of the brain during the night. And this particular measure is just incredibly sensitive. We can look at whether or not a person’s asleep or not, but also the depth of their sleep. And I’m going to be talking a little bit about these different stages of sleep today. One’s a very kind of a light sleep, which is typically called the stage one or two. Three and four are delta sleep or slow-wave sleep or deep sleep. It’s where we get really restorative functions for our sleep. And then we have REM sleep, or R-E-M sleep, rapid eye movement sleep, which is a time when we dream.

And there our EEG, our brain, actually looks like it’s awake, very similar kind of EEG pattern as compared to what’s going on during the day, except we are completely paralyzed. We’re not able to move our bodies, our body, except for our eyes move back and forth in these rapid eye movements from one side to the other. So of course, across the course of the night, we go through each of these stages. So sleep is a behavioral state. It can be very readily evaluated by objective measures, and we also have subjective scores that evaluate how well people are sleeping.

Rachel Ehrenberg: And if I understand right, the body is actually very busy when we’re sleeping. I’m not talking about so much memory consolidation and things that are going on in the brain, but in terms of the immune system. Tell us a little bit about when we get a good night’s sleep, what’s going on in terms of the immune system.

Michael Irwin: Yeah. That’s a really great question, Rachel, because what’s going on during sleep is a very active and dynamic process in which the body and the brain are communicating with each other throughout this period of behavioral state. And allows the body then to restore and to rest, because there are changes in the metabolic demands on the body during that period of time. And the brain, and during sleep, is coordinating those kinds of changes. At the more cellular level or molecular level, we find changes in the immune system that are also occurring.

And one of the things that is happening is that all of the bodily systems — the autonomic nervous system, the hypothalamic pituitary adrenal axis, which is the stress hormone processes, and the immune system — are all aligned with our circadian rhythm. But there are also specific changes that occur during the night and during sleep that are driven solely by sleep.

So one of the measures that we often think about is inflammatory measures. Inflammatory measures, as we’ll probably talk about a little bit later today, are really very important in a number of disease processes. Certainly, they increase with aging — that puts us at risk for chronic diseases of aging, certain cancers, cardiovascular disease, dementia and also depression.

So these inflammatory products are very important, and they’re regulated very tightly by sleep processes. One particular inflammatory cytokine is called interleukin-6, which is secreted by immune cells or inflammatory cells in the body, and it communicates with other immune cells to coordinate the immune response.

I don’t want to give you the impression that all inflammation is bad, because some inflammation is necessary in order for our immune system to respond to an infectious challenge or bacteria or virus, and mount an effective immune response.

And so what’s very key during the night is that the immune system is being coordinated by some sleep, and sleep is actually producing a mild activation of these inflammatory products, which we believe is important for preparing the person for the kinds of recent exposures that might occur during the day. But also, if a person has been exposed to an inflammatory agent or infectious agent, that low-level inflammatory response allows immune system to respond as a person is resting during times of low metabolic demand so there can be an effective metabolic and immunological response to that infectious challenge. So I can go a little bit more into detail about how we measure this. And what we’ve done is we’ve placed …

Rachel Ehrenberg: Let’s circle back to that.

Michael Irwin: Sure.

Rachel Ehrenberg: I am very interested, but I also want to make sure we touch on some of these other things. I’m going to make a note to circle back to that, though.

Carmela, I mean, already, we have a sense of the importance of resting and the sort of repair, restore or preparative fight mode that the immune system is in. What are some of the health outcomes that are related to poor sleep when this is disrupted?

Carmela Alcántara: Yeah, thanks, Rachel, for that question. And Michael started alluding to that in his response earlier. What we know and what’s increasingly recognized is that sleep is really now considered the third pillar of health. So it’s commonly accepted that diet is a pillar of health, that exercise is a pillar of health. And now more and more, I think there’s more acceptance and common knowledge that sleep is also a pillar of health.

And what I mean by that is that sleep really affects our entire mental health, our physical health — really, all aspects of health. And there’s been several studies and systematic reviews and many analyses that have confirmed that different dimensions of sleep, one of the most consistently studied aspects of sleep is short sleep duration, which many of us and many of us on this webcast here can relate to. And that being sleeping less than seven hours of sleep, for example, is associated with increased risk of premature mortality, increased risk of cardiovascular disease, depression, cancer, cardiometabolic conditions, like obesity, diabetes, hypertension. Really, in addition to increased risk of workplace accidents, of motor vehicle accidents.

Really, it sort of is an important pillar of health. It touches every facet of life. And we start seeing effects on health, not just in adulthood, but you can go back all the way to the beginning, early in the life course, to see the impact of sleep disturbances generally on health. So we’re focusing on adult health, but really you can think about the effects of sleep disturbances on pediatric health as well.

Rachel Ehrenberg: We just did a story on naps and kids and the role they may be playing in learning and memory. And I know some of your work has also focused on teenagers as well. And there’s a lot of discussion about school start times and sleep for teenage health.

Michael, some of these health outcomes, is a lot of this do we think mediated by the immune system? We know that inflammation and some of these ills go hand in hand. Do we know much about cause and effect? I imagine there’s some kind of cyclical thing, too, where if you’re getting poor sleep, you then have poor health and that then may contribute to also having poor sleep. Can you talk about that a little bit?

Michael Irwin: Yeah, absolutely. That’s a really great point. So inflammation — and immune system — plays a really critical role in a whole host of disease processes. And I made a list of that already, so I’m not going to go through that again, but we know it’s important in cancer, cardiovascular disease, dementia and depression. And sleep is really driving many of those changes. And we know that sleep disturbance is occurring in each of these disorders as well. But I think the question that is often raised is which comes first? Does the chronic disease come first and then lead that to inflammation? Does inflammation come first, leading to changes in these disease outcomes?

And we know from prospective studies that changes in the inflammation, increases in inflammation, are really very key in the risk of these diseases and that we can prospectively evaluate and look at measures of these inflammatory products early and then follow people over many years and find that people with higher levels of these inflammatory products, C-reactive protein and interleukin-6, are more at risk for each of these diseases that I mentioned. We can also do studies of a similar nature and look at reported sleep disturbance and objective sleep disturbance, and polysomnography measures and find that disturbances of sleep are also related to each of these disorders. And importantly, also related to mortality.

And so there have now been a number of studies that have actually evaluated sleep and inflammation in a prospective design and found that sleep disturbance occurs first leading to the increases in inflammation, and then the inflammation mediates these increases in disease risk. So we know that there’s this particular pathway, but we also know that when people have chronic diseases of inflammatory activations, such as cardiovascular disease or rheumatoid arthritis, and also certain infections, that changes in the immune system occur, which lead to alterations in sleep.

So this can produce a vicious cycle, where you have a disease that’s producing changes in inflammation, and then changes in sleep, and then changes in sleep produce further inflammation and further worsen the disease. So very important strategies are to target either both of these particular mechanisms, sleep or inflammation, or one or the other. And a number of groups throughout the country are interrogating that kind of two-hit approach to prevent depression and potentially alter risk for dementia and other neuropsychiatric disorders.

Rachel Ehrenberg: Very interesting. Maybe we’ll get to circle back to that again. And I should add, I should have said this at the top, there is a chat box and a question box. Please throw your questions in the question box and in about 20 minutes we will start fielding those questions. And you’re lucky to have two experts who can help with your sleep queries.

So we’ve sort of been talking about within the island of the body. Carmela, tell us about some of the environmental and social factors that contribute to poor sleep, disrupted sleep, poor sleep health.

Carmela Alcántara: Yeah. Thanks for that, Rachel. I think before I go to some of those structural or social environmental explanations, I think it’s good to take a step back to acknowledge that even though sleep disturbances are ubiquitous in America, in the world, they’re not evenly distributed across the population and you alluded to this in your introduction. But what we know is that racial and ethnic minorities compared to non-Latinx White populations, those from low socioeconomic status groups compared to those with higher socioeconomic status are at higher risk to experience or suffer from many of the sleep disturbances that we’ve alluded to today.

And one important thing to highlight, as I mention this, is that while there’s been very consistent evidence to show that these sleep disparities exist, what they don’t indicate is that these sleep disparities are due to some genetic differences across races, or for biological reasons, which is why research to really try to understand and move beyond just documenting these differences across racial/ethnic groups is so important. So in order to understand why there are sleep disturbances or disparities in sleep disturbances, it’s really important to take a look at what we refer to as social determinants of health.

And social determinants really refer to the nonmedical factors and nonbiological factors. So think the structural factors, the contextual factors that really shape access to risks and opportunities that end up putting people at higher or lower risk for certain conditions. Some examples of those structural or contextual factors include where people live, where people work, where people play, the kinds of policies, their exposures to structural racism, their exposures to racism in the health-care system, or access to certain kinds of health care for the specific problems, exposure to discrimination — for example, stresses related to their immigration status or to other social identities.

So again, these social determinants are really important in trying to understand what are the nonmedical, nonbiological factors that really contribute to the disparities that we’ve observed for, I think for decades now. There’s been a lot of increasing research in the area of sleep health disparities, which is terrific. There’s a lot more that we need to know. So, for example, while we know that there’s consistent disparities in the prevalence of short sleep duration, where racial/ethnic minorities are more likely to sleep less than seven hours compared to non-Hispanic whites. There’s a lot of within group comparisons that have yet to be — in research examining within-group comparisons — that have yet to be done.

So, for example, thinking about intersecting social identities. So focusing on differences in the prevalence of these conditions, by focusing on the intersections between gender, between socioeconomic status, between sexual orientation. There is so little. Most of the time a lot of this research and sleep health disparities has focused on making really broad, general comparisons across racial/ethnic groups. But what we know is that there’s so many differences within racial/ethnic groups. And the bulk of my research has focused in this area and in the area of Latinx sleep health disparities, where many, particularly for Latinx immigrants, they’re coming from so many different countries throughout Latin America, and yet they all get lumped into this category of Latinx.

So what does it mean to really unpack? In order to really unpack and understand sleep disparities, you really, we need these descriptive studies, we need also some more mechanistic studies. And with greater attention to these intersecting, we might refer to as intersecting, social identities.

Rachel Ehrenberg: Yeah. These groups — I mean, even the word “group” — they’re certainly not homogenous. And it does seem like, are we getting there? I mean, a lot of the research to date, how much of that is observational, documenting? It seems like some groups — there’s that word again — but fall by the wayside, there’s been maybe way more attention in some aspects than other. Are we getting there?

Carmela Alcántara: I think we’re closer than we’ve ever been. I was really excited to see that there’s been a lot of research trying to understand differences between black and non-Hispanic, non-Latinx, White groups. Increasingly more research on trying to understand differences in sleep disturbances within Latinx communities. What we know is that there’s been historical very little research into American Indian and Indigenous communities. And even trying to understand the heterogeneity within the Asian, Asian-Pacific Islander community. I think there’s been recent calls, and recent calls from federal funders to address this scientific gap, but there’s a lot more research and investment, I think, to really try to unpack these sleep health disparities that lies ahead for all of us who are really interested in this area.

And I know we’ll talk about this a little later, but there’s the describing, and the trying to understand and document where there are these differences. And then there’s research that’s focusing on actual solutions. And so what do those multilevel, policy-level solutions look like to really address sleep health disparities? And those require different approaches and have different implications in terms of the kinds of outcomes and the time horizon, but both are really vastly important.

Rachel Ehrenberg: We’ve been talking a lot about physical health, and I want to touch on mental health. For me, when I’m worried, that’s when I have trouble sleeping, when I’m really worrying about something. And tell us — let’s start with you, Michael — about sleep’s relationship with depression, with mental health.

Michael Irwin: Yeah. That’s a great segue way into what I’d like to talk about because what Carmela’s addressing was this interaction that’s taking place between the individual and the social environmental community. And I think of these big loops of interaction that are occurring at that level, but then I’ve spent some time already talking about the interaction within the person and those micro-loops. The social-environmental stressors that we’re all experiencing are impacting our sleep, but they’re also impacting our perceptions of stress, which can lead to depression.

And so, as we’re waiting, I have full confidence that we’re going to move forward with public policy issues addressing them, but as an individual and as a clinician, I also know that we as individuals can be empowered to respond to these social environmental stressors in different ways. And many of our responses can lead to increases in stress and increases in disturbances of sleep and increases in depression. But there are approaches that we’ve been pioneering in the Cousins Center at UCLA and the Mindful Awareness Program that actually address these mindfulness and the essential awareness that can happen, which we have demonstrated can reduce perceptions of stress.

And I emphasize, it’s not that the stress is going away, but how we are perceiving it and how that perception is activating the stress response pathways, which having all these damaging effects upon the body through the immune system, leading to depression and leading to sleep disturbance and leading to the other diseases we just talked about. So mindfulness practices, which are very relevant in our days with high stress and activities, we know that they can decrease stress and decrease depression, but they also can reverse maybe the inflammatory changes and can do so both at the molecular level, but also at the genomic level by altering which genes are activated and which genes are turned off.

And during times of stress and depression, there’s an activation of inflammatory genes. And the mindfulness approaches can actually turn off those genes and decrease that level of activation. So they’re having powerful relationships. Why is that so important? Because we know that when inflammation is occurring, it puts us at greater risk for not only having depressive symptoms, but then also developing a major depression.

And we also know that when we target or improve sleep, because we just recently published a trial of over 300 older adults that had insomnia who were not depressed, who were then followed over three years, and we gave them two treatments, a cognitive behavioral therapy for insomnia or a control. And the people that received the cognitive behavioral therapy for insomnia have a 50 percent reduction in the likelihood of getting depressed. And if they had a sustained remission of insomnia, that reduction was over 83 percent.

So by targeting sleep, we can significantly decrease the likelihood of getting depressed. But I emphasize that other interventions, such as mindfulness and mindful approaches such as tai chi or yoga are non-inferior. That is, they’re similar in their benefit improving sleep. And it appears that they may also have a very important role in the prevention of depression, in people that have insomnia problems and sleep problems.

We also have data that the pathway that’s leading to that prevention of depression ... as the sleep disturbance goes away, inflammation goes away, and as that inflammation goes away, the risk of depression also is mitigated or lessened. So we think that there’s actually these pathways that are occurring. The reason that we’re doing these kinds of studies, there’re all this experimental data that we’ve also accumulated, where you could take people that have sleep disturbance or that have this acculturation stress or this severe stress in their communities and bring them into the laboratory and see how they respond to sleep loss and how they respond to immune activation.

And we know that these pathways are really salient for predicting who gets depressed and who doesn’t get depressed, and who can experience reward and pleasure in their lives and who doesn’t. And so we know that all these factors are interacting and we need to then, we’re breaking those apart in these clinical trials and targeting one particular aspect versus another and finding benefit for the patients.

So coming back to Carmela’s point, yes, we really have huge problems facing this country and throughout the world, but we as individuals are having power to address many of these things by incorporating stress-management approaches such as mindfulness that can attenuate these underlying biological and psychological processes.

Rachel Ehrenberg: How can people access this kind of help and training? I don’t live in LA, I have good health insurance, but I’m more privileged than many. And is this something where — and I want to ask each of you — Michael, we’ll continue with you for the moment. Is this a matter of training physicians? Is this something people can find things related to this online on their own? How do we bring what’s known that can help to people?

Michael Irwin: Just like Knowable, the Mindful Awareness Research activities which are at UCLA are completely free. Completely free. And so I encourage your viewers to download our app, called UCLA Mindful. And UCLA Mindful has free meditations. It provides also an introduction to the curriculum that we have shown has been effective in decreasing inflammation, improving stress and sleep problems. So I think there are many other kinds of apps out there for mindfulness, but most of them do not have a research evidence behind them. And we’ve spent over a decade generating research evidence about the effectiveness of the mindfulness of the curriculum that we’re teaching.

It’s based upon mindfulness stress reduction, but it’s much more accessible because it doesn’t require a full-day retreat, which we know that many people in the community cannot give up a full day to go off on a retreat. So it is completely for free. It’s been translated into Spanish and on the UCLA Mindful app, there’s a Spanish version that you can also access. And we’re now translating it to, I think, over a dozen languages. You have a very multicultural community at Los Angeles, and there’s a huge demand for the mindfulness that’s been featured by Governor Newsom as a California resource at the time of Covid. So it’s been very widely used and recognized. It’s also available, going onto our website. So it is a freely accessible approach for obtaining mindfulness training. So I’d encourage people to do that.

Rachel Ehrenberg: Great. And Carmela, tell us a little bit about reaching at-risk people. I know you’ve also been working on a Spanish translation of some cognitive behavioral therapy, but just translating into another language doesn’t necessarily reach people. Go ahead.

Carmela Alcántara: Right. Yeah. I think just a couple of thoughts. I think one thing that both Michael and I are emphasizing indirectly is that we have both been referring to these behavioral treatments for sleep disturbances, and actually there’s a lot of strong evidence base to support the effectiveness of behavioral treatments like cognitive behavioral therapy for insomnia. I think mindfulness-based stress reduction and some other behavioral therapies for different kinds of sleep disturbances over medications, for example, as having a long-term impact for improving sleep.

So I just sort of want to sure that viewers are hearing that, because often medications, or even over-the-counter medications end up serving as the first treatments, or sort of self-treatments, but in fact, just encouraging people and making sure that they know that the evidence base for behavioral treatments for insomnia, in particular, and for other more general sleep disturbances is quite strong. With that said, and it’s really terrific Michael to hear about the translation work and adaptation work and the digital app and treatment and the effectiveness, because there has been such an increase, an explosion, and part because of Covid, in part I think because of the digital revolution in interest in digital mental health treatments.

And so my group is addressing that issue, but in the case of insomnia and specifically for Spanish-speaking primary-care patients in New York City. And so we’ve used a pretty rigorous cultural adaptation framework to adapt cognitive behavioral therapy, digital program of cognitive behavioral therapy for insomnia for Spanish speakers. And the hard part is addressing, how do you incorporate and attune to these social determinants that I alluded to before, whether it’s acculturation stress or discrimination, or sort of people’s social identities, or acknowledge where they live and what they have control over or not, in terms of the kinds of recommendations that are given to improve sleep.

And so that entire process is much more than translation. It’s really about thinking, how do you address these contextual factors? How do you address and incorporate sociocultural values into the treatment such that you can also maximize the likelihood that this now-digital program is actually going to be used and adopted and implemented? So I think there is generally, and we know this from lots of other research, a lag between the research that’s produced in clinical trials, and then when it gets implemented into communities, and that’s a long lag. And you just heard great examples from Michael of ways in which their, I think, team is addressing that live.

But by and large, we know that a lot of clinical trials have actually not included some of these groups that are at higher risk for sleep disturbances. So we did a big systematic review of all behavioral trials that address sleep issues, and found that only 7 percent of those actually targeted any underserved group, whether it was racial/ethnic minorities, linguistic minorities, sexual minorities, immigrants, I mean, sort of, we had a veterans, we sort of had an extensive list. And so that work, there’s so much more work that remains to be done, but it is true, I think as a field, we have a lot more work to do in terms of implementation and really trying to both adapt, test — I think testing is really important, making sure that what is being disseminated is known to be effective.

And you heard Michael allude to that, we’re going to test if it’s going to work. We’ve invested a lot of time in adapting the treatment, but it’s really important before it’s disseminated into any community that we know that it works. That’s the hallmark of good science, and I think of psychology. And the psychology profession, our charge is to really ensure that the treatments that are being implemented are indeed evidence-based.

Rachel Ehrenberg: And there’s also this bigger — which you spoke directly about — I mean, the bigger structural racism in terms of, do you live in a ZIP code with light pollution, noise pollution? Have the medical community, having physicians be more trained across diverse patients. So there’s also this larger scale. I mean, I think on the one hand that’s very kind of overwhelming and intimidating like, “Oh, we just have to fix structural racism and then sleep will be better for a lot of people.” But also, I just want to remind people, which I take to heart, structural racist policies, harmful policies are constantly made and remade, which means we can remake them better. This isn’t something that people should feel that it’s just so embedded that you have to give up.

Carmela Alcántara: Yeah, I totally agree, Rachel. And I just want to sort of echo there’s definitely room for both. I think focus on alleviating acute clinical suffering, and at the same time working to create policy solutions for some of the very problems that are the direct result of structural racism or legacies of racism. So I think there’s room for both and certainly a need for both.

Rachel Ehrenberg: Well, it’s about time to take questions. So I’m sure we’ll get into a lot of the stuff we’ve touched on. Really quickly, briefly, each of you tell me — start with you, Carmela. What are your sleep habits? Do you get seven hours-plus a night?

Carmela Alcántara: You know what? I’m very proud to say I do practice what I preach here. I think that wasn’t always the case, but certainly I think the more and more I’ve learned. And honestly for me also as a Latina woman and sort of understanding my own risk for health disparities and other things, being able to practice good healthy behaviors is really paramount. So I do get my seven hours of sleep when I can. We run a tight ship. I have a four-year-old here. We run a tight sleep schedule too. Sleep is pretty important here and I think to the extent… sometimes it’s not to say, there aren’t exceptions, but by and large, try to get those seven hours of sleep.

Rachel Ehrenberg: OK. And Michael?

Michael Irwin: Yeah. Sleep has been very important to me. One of the hardest things about becoming a doctor was having to give up my sleep and the stress I was experiencing. So even when I was a medical student, and also that was in the ’80s. And so that’s kind of how old I am. And so in the ’80s, I was practicing yoga and also engaged in some mindfulness practices to deal with the stress, which I thought was really important, so that when I did have the time available, I could get sleep. So I learned straight from that over the years and had to come back to it again and again.

And I know the stresses of raising a child and the disruptions of sleep. When you have a young child, your sleep becomes disrupted naturally and then suddenly you have this behavior that you’ve learned where you can’t sleep. And so you have to retrain yourself again. And so that keeps happening again and again. And coming back to the simple approaches of either cognitive behavioral therapy, or this mindfulness approach that I mentioned.

But I just want to emphasize what Carmela also mentioned. So it is that, medications are not the answer because medications, once you stop taking them, mostly problems come back. And particularly older adults it can lead to a whole host of other risks and problems. So I do practice what I preach. I’m not totally disciplined, but I keep trying and working on it every day.

Rachel Ehrenberg: So related to that, we’ll go right to the questions. And there are a lot of questions on aging and sleep. One, do we know why older men and women begin to have sleep problems? And then, what can elderly people do to improve sleep which is difficult with, you may have an increased number of bathroom visits in the night, perhaps dementia or other mental health issues are complicating what were once regular routines? Michael, do you want to start with that one? Carmela, jump in?

Michael Irwin: So I’ve been working with older adults for over 20 years. And one of the things I’m really always shocked with is people that are older will either come and they’ll say, “I just can’t sleep.” And I say, “Well, how many hours are you sleeping?” “Well, I’m getting almost seven hours of sleep. I’m not getting my full eight hours.” And I remind them that eight hours of sleep is not what you’d expect as you get older. Seven, six-and-a-half hours of sleep is certainly within the normal range once you’re older than 60, 65 years of age. As we age, there are changes in our brain. There’s changes in the nature of sleep. And one of the things that happens beginning as early as 35, 40, is that we begin to lose that slow-wave sleep, that deep, restorative sleep.

And there’s not really much you can do to get it back as you lose it over time, but there’s ways that can accelerate or slow it. So if you drink a lot, guess what? Your loss of slow-wave sleep is significantly accelerated. So it’s very important to monitor your alcohol.

But as Carmela mentioned, there are pillars of health and good diet, and particularly exercise is really critical for maintenance of good sleep. And we know that when you exercise on a regular basis, the amount of slow-wave sleep that you will have during the night is greater.

So exercise has a protective rule for a whole host of diseases. And particularly, it’s probably through this activation of neurogenesis and neuroprotective processes which preserves the nature of sleep and also many other brain functions. So exercise is very important. So that’s an approach. I already mentioned mindfulness that also has protective approach around the brain. So there’s biological changes that we can really not reverse and change, but there are things that we can do that can slow that trajectory of aging.

Carmela Alcántara: I think one thing, Rachel, and this isn’t directly related, and I’m sure Michael, you have the expertise to sort of back it up, but it’s not too late either. So if you have been someone who’s been struggling with sleep issues your whole life, and you’re in your 60s, it’s not too late to make a change or to want to start to implement different behavioral techniques to improve your sleep. And so I think there’s just a note of optimism there because it can feel pretty daunting, I think, to sort of want to change a behavior and a pattern that you’ve sort of have maintained for so many decades, but it isn’t too late. You can benefit from those health, from those changes and benefiting your health in your older adulthood as well.

Rachel Ehrenberg: And Carmela — you both have a lot of expertise, so I’m just sort of bouncing back and forth, so feel free to chime in after each other — but are there, in terms of shift work, I guess there’s one question asking are sleep problems related to shift work worse if you’re older? But then also, just what practical advice for nurses, someone who’s doing the work night shift in any number of places, is it better, the person asks, Alison Barnes. Is it better to adjust and shift your patterns, to stick with one pattern? I’m not sure if that’s even on your days off. What advice do you give to shift workers?

Carmela Alcántara: Yeah. That’s a great question. I think something that sort of I’ll add, and there’s been a lot more, I think research into the impact of sleep regularity on health. And so I think, Alison, your question or your intuition about trying to maintain a set sort of sleep schedule and wondering when and where, and the timing of that is really important, because maintaining a sleep schedule is indeed pretty important having a regular, or more regular, sleep in terms of reducing that night-to-night variability to the extent that you can is really important. I think without knowing sort of specifics of your case, I think keeping that principle at the forefront is really important.

So evaluating your schedule and trying to understand the extent to which you can keep that. So if you’re able to have dark-out, sort of blackout shades, and even if it’s again during the day, but becoming more regular in your sleep and because that yo-yo-ing sort of effect is really problematic. So if on your days off, you’re sort of trying to adjust to a daytime schedule, that’s going to be pretty problematic. So the extent to which you can establish some more regular sleep routine, that would be helpful, but without more details, I think about your exact schedule, it’s harder to provide more specifics.

Rachel Ehrenberg: There are a lot of questions about sleep and specific health issues: snoring, tinnitus, ADHD, bipolar disorder, obesity, autism. We’ve talked about lack of sleep or disrupted sleep upping the risk for a disease. Are there some diseases in particular that affect sleep and others less so, and are there recommendations for improving sleep? Do those get really specific depending on the disorder, the health difficulty the person’s dealing with, or is there sort of general… we’ve talked about mindfulness. I’m actually not sure what the cognitive behavioral therapy entails. I don’t know if one of you wants to talk a little bit about that. And would these kind of approaches work probably across many groups or is it sort of, no, that’s really just for depression, or maybe we don’t know?

Michael Irwin: Well, a whole number of diseases that have an inflammatory basis can lead to sleep disturbance: rheumatoid arthritis, cardiovascular disease, depression. And so those comorbidities between that disorder and sleep disturbance are very common. And additionally, we also know that cancer patients and cancer survivors have very high rates of sleep disturbance. So there’s a number of complex issues that are going on. Do you then just take a one-size-fits-all and deliver a treatment such as CBTI [cognitive behavior therapy for insomnia] or mindfulness to a population that has an underlying biological basis that may increase their risk of sleep disturbance?

And we don’t fully know, but we do know that when you take CBTI or mindfulness approaches and deliver them to rheumatoid arthritis patients or to cancer patients or to cardiovascular disease patients, they are equally effective. So it suggests that, yes, there may be an underlying biology that’s driving that sleep disturbance, but the approaches that we use to treat the sleep disturbance are beneficial in those populations. And similarly beneficial is found in people that don’t have those comorbidities. So that, I think, is very important message that if you have that disorder, you can receive a benefit.

There are other disorders such as having pain problems and chronic pains, which is osteoarthritis, and we know that pain and difficulty, experiencing pain can lead to problems with sleep. And so therapies or cognitive behavioral therapies that target pain that are coupled with targeting sleep appear to be very important, because if you can improve pain, you can improve sleep. And if you can improve sleep, you can also improve pain. And so that kind of dual approach in a person that has two symptoms of pain and sleep problems can be very effective.

So I do think we need to do much more to tailor these particular approaches to the disease population, taking into account their symptoms, but we also know that these general approaches, which are targeting the sleep problem or the depression or the pain, can be effective for altering not only that symptom, but sometimes the outcome for that particular disorder.

Rachel Ehrenberg: Carmela, can you briefly — I want to try and get to a couple more questions. We’re running short here, but this cognitive behavioral therapy in Spanish that you are working on, can you just give us some of the, for example of the kinds of things that cognitive behavioral therapy for sleep would entail?

Carmela Alcántara: Sure. So cognitive behavioral therapies in general focus on both changing maladaptive thoughts that might be contributing to a specific condition. In this case, it would be insomnia and also maladaptive behaviors that are also contributing to insomnia. And so for cognitive behavioral therapy in particular, there’s a lot of focus on teaching ... what is sometimes referred to as like sleep education or sleep hygiene. So there is an emphasis on sort of teaching people basic, some general skills and lifestyle skills for improving their sleep. And those are often recommendations or tips.

It also involves really keeping track of and understanding people’s sleep more generally and the quality of their sleep for some time. And then really sort of adapting the scientist mindset to people’s sleep and almost sort of trying an experiment where in fact you might even be restricting your sleep for some time and observing the impact of sort of this restrictive sleep on your sleep in the long term. And also addressing some of the maladaptive thoughts that might be impacting your sleep.

So it’s really this package or suite of skills that you learn in cognitive behavioral therapy, where there’s a heavy focus on learning what’s almost this paradoxical part of sleep, of the treatment that’s called sleep restriction where you’re actually for some short period of time sleeping less in order to get more practice with what it’s like to get high-quality sleep. And then also sort of learning skills to help you address any sort of behavior issues that might be affecting your sleep. I think Michael had alluded to alcohol use.

There’s ways in which you can really sort of architect or design your room and your living situations to improve your sleep. And then separately, there’s that focus on the cognitive or the thoughts that might be contributing to some of those negative sleep patterns that are contributing to your insomnia. So it’s this suite of skills that you’re learning in cognitive behavioral therapy and what our team has done is really how can we take that and adapt it now for immigrant community, Spanish-speaking community and an urban community as well.

Rachel Ehrenberg: Fascinating. This is also related. So some people are asking, how can they get more deep sleep? Light and REM sleep seem to be fine, but are there practices to actually get more deep sleep? And a sort of preemptive question to that is, how do we know whether we are getting light, deep or REM sleep? Is any sleep good, or should we be trying to engineer getting set amounts of particular kinds of sleep?

Michael Irwin: That’s a really critical question. I mean, there has been a whole host of studies that have tried to actually increase slow-wave sleep by giving pharmacologic agents and also neuropeptides like growth hormone releasing factor. They’ve not been terribly effective. And we don’t really know why. Maybe that there are really fundamental changes that occur as we age, for example, that become very fixed in the regulation of sleep. So I’m not sure that a person, and I certainly am not focused on the actually amount of slow-wave sleep I have, but to what extent I’m waking up feeling restored and rested.

And I know those feelings of being restored and rested can be facilitated by some simple approaches. One is not drinking so much or not drinking before you go to bed, not exposing yourself to light in watching your computers or TV, or this blue light that you get from your iPads or your electronic devices will disrupt your sleep and produce a lighter sleep.

Exercising on a regular basis is also very important — but not exercising at night because exercising in the late evening can elevate your body temperature, making it more difficult to go to sleep and have that very deep sleep. Your body temperature needs to begin to decrease in the late evening and early night for us to have that deep sleep.

And also ambient noise and ambient light are also very important. And Carmela mentioned that. And I think we know that many communities can’t really control that because they’re experiencing ambient noise, but there are earplugs and other devices that you can now put in your ears that can really significantly attenuate that experience of noise, and also night shades that you can wear that will block out that ambient light and also improve sleep.

So those are very simple approaches that we can do to increase the restorative sleep, which we know from a number of laboratory studies is associated with the amount of slow-wave sleep, but living in the community without all these EEG measures, you’re not going to ever know whether you’re getting more slow-wave sleep versus not. So simply tracking whether or not sleep is more restorative and wake up feeling more restful is what I do and what I would recommend people in the community to do to track their benefit.

Carmela Alcántara: Yeah. And I’ll just add, Rachel, for listeners who have insomnia, we also know that there’s sort of this tricky sort of relationship with tracking too. Tracking is important for sleep, but we know that people with insomnia are more likely to ruminate about their sleep and that’s part of, I think the issue. So just being really careful also with tracking, especially because there is such a… tracking your sleep through lots of different commercial devices has become quite popular. And so just being mindful, I think for people, particularly those who are suffering from insomnia, tracking is good, but really in sort of a limited kind of fashion.

Rachel Ehrenberg: I recently learned about the phenomena of biphasic sleep that before there was electricity everywhere, it was quite common to have a first sleep and a second sleep, where people went to sleep around dark and slept, and then were up for a couple of hours in the night and then slept again. And that, what you just said, Carmela, about not getting too crazy about, “Oh my gosh, I’ve woken up in the night. My sleep is disrupted. My health’s going to deteriorate,” but to pay attention to the number of hours you’re getting. Try to engineer things. Someone asked about any options other than earplugs for a snoring partner. And I have an aunt and uncle who don’t sleep in the same bedroom anymore because of the snoring issue. So trying to do the best you can.

I’m very sorry to report that we are the end of the hour. That’s all the time we have. There’re so many more questions that people had and that I had, but I just want to thank everyone in the audience for joining this event. If it’s been a good experience for you, please consider providing a donation to help us meet our mission of making high-quality science coverage freely accessible to all. You can do that at our website, I want to thank the Alfred P. Sloan Foundation and the Gordon and Betty Moore Foundation for their wonderful support of Knowable Magazine.

And of course, very special thanks to Carmela and Michael for their fascinating discussion. Really appreciate you being here today.