How to Use Light to Deal with the Winter Blues (Dr. Michael Terman)

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It’s a familiar feeling for many of us over the winter months: the light fades, the darker days settle in and your mood dips. It can feel hard to get outside and hard to do really anything. Motivating yourself off the couch becomes an even bigger challenge than normal.

But there’s steps you can take to counter those feelings. In this episode Dr. Michael Terman, an expert in treating seasonal depression with light therapy, shares his best tips and findings for getting through the winter months with your mood and sanity intact.

Some of the good stuff:

Some of the good stuff:

[3:35] Dr. Michael Terman’s favorite outdoor space

[5:23] How he got into the study of light therapy and circadian rhythm

[6:41] What his research found

[10:52] What light has to do with depression

[16:28] Where is it a problem?

[19:15] Does this have to be a problem year after year?

[26:33] What does going outside have to do with it?

[34:09] What is a light box and how to find one

[44:44] Dr. Terman’s favorite outdoor moment

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Follow us on Instagram and share your outdoor life with the hashtag #humansoutside365.

Here’s an edited transcript of our conversation on The Humans Outside Podcast.

Listen to the episode on iTunes, Google Podcasts, or wherever you find your favorite podcasts.

Amy Bushatz 0:06

It’s getting dark here in Alaska. You might have heard that it’s always light here part of the year and always dark the rest of the year, the sun either never sets or never comes up. And while that is true very far north in the state, here in the Anchorage area, where the vast majority of the state’s population lives, our shortest day’s sunrise is at about 10:15am and sunset is at about 3:45pm. And thanks to hints of daylight before and after that, you’re looking at around six hours of usable light on the shortest day of the year, right before Christmas. Okay, so that’s not a lot of daylight. If you work a regular schedule or go to school, anything resembling nine to five, you’re missing all of it while inside your office. I have ways of combating that, like making sure I take at least a short walk daily while it’s still light outside. But even if you’re doing a daily 20 minute habit, you still might not make it outside when it’s light. And while things aren’t that dramatic darkness-wise where other people live, shorter daylight impacts us all over the winter months. And so can that sinking feeling of darkness called Seasonal Affective Disorder or SAD and related problems. How can we get through it and what role does heading outside play? Quick caveat here. We’re about to talk about some stuff like depression that should also be discussed with your doctor or mental health provider. Obviously, nothing we say here should replace that. And if you’re feeling depressed, I really want to encourage you to seek help. We’re all about getting help here, which is why we’re so lucky to have someone with us today who’s one of the top experts in the country on SAD and circadian rhythms. Dr. Michael Turman is the president of the Center for Environmental Therapeutics, has a doctorate degree in physiological psychology from Brown University, and is a Professor of Clinical Psychology in Psychiatry at Columbia. He studies drug-free therapy for these problems, including things like light therapy, and it’s a really incredible opportunity to have him here with us today. Here’s our conversation. Dr. Terman, welcome to Humans Outside.

Michael Terman 3:10

Sounds very interesting. I’m looking forward to it.

AB 3:14

Well, thank you so very much for your time. We always start these podcast episodes in our conversations with our guests, just sort of like imagining ourselves with our guests in their favorite outdoor space, wherever they may be. And so I’m hoping you can describe what your favorite outdoor space is and maybe we can imagine ourselves with you there today.

MT 3:35

Uh huh. Well, a little bit of background. I was born in Hell’s Kitchen on the west side of Manhattan. Not your favorite place for being outdoors. So when I managed, and I’m still here in New York, when I managed to get outdoors, my favorite place is not that far away. It’s at the eastern end of Long Island Montauk Point where I’d like to go camping on the beach.

AB 4:10

Hmm, that sounds very pretty. You know, I grew up in California. And while we had campsites near the beach, it was an entirely new concept for me that people actually camped on the beach after I left there, because it’s just not something that this state lets you do.

MT 4:30

And this is a state campground. Yeah. What do you know?

AB 4:35

There you go. Okay, so you’ve told us where you’re from, but we usually start our episodes hearing how our guests became someone who likes to go outside. So you know, being from New York City, what’s your story? How did you become someone who’s interested in this?

MT 4:50

Well, you crave it, right? You don’t have it, so you crave it. And we always did this as kids. My parents would take us camping and so it just became part of me. And I look forward to it every year.

AB 5:08

Hmm. And what you’re known for is understanding and leveraging the environment to help us psychologically, which you call Environmental Therapeutics. So can you tell us how you got into that?

MT 5:23

Rather through the backdoor. I was working on my PhD studies at Brown, and doing work with animals on their day/night cycles. This was in the early days of circadian rhythm research. And that involves turning the lights on and off on different schedules. And I was able to develop some powerful methods for moving the biological rhythm earlier or later, depending on the schedule. Then, I heard that the National Institute of Mental Health had been doing the same thing, but with people who were getting depressed. They had a clinical application for what I was doing in the animal lab. So I bolted over to psychiatry, came back to New York. And that’s how it all started.

AB 6:36

And what did you find in that research?

MT 6:41

Well, we’re working with people who have become severely depressed once a year, in the winter months, and look like completely different animals in the summer. And that applies not to a majority of the population, although you see traces of it throughout the population. But here we’re working with people who meet the psychiatric criteria for a major depression. And they can predict when it’s gonna come in, and slightly different for each individual, it may start in mid September, or mid October. By Thanksgiving time, you’re gonna have if you’re gonna get it, and then adjust spontaneously. It resolves itself. In March and April, and by May, everyone is back to normal, for a good summer. So that’s the pattern we were dealing with. And the idea was, can we intervene as these really debilitating symptoms set in in late fall? Can we proactively prevent the episode from setting in, or if it has already set in, can we pull people out of that episode, and make them feel like springtime, come December and January. So that was the goal of the research. And we developed methods that managed to do that quite nicely, and without antidepressant drugs. And that, I think, was the important insight. Because traditional psychiatry over the last 30-40 years is to give an antidepressant when somebody crashes like that. And we’ve been able to bypass that requirement and do so with excellent results.

AB 9:15

So you’ve described people who are clinically depressed, seriously depressed, but is it possible for these seasonal mood swings, I guess, to impact someone who’s not deeply depressed? Like, can someone still feel that without being all the way over the edge of clinical depression?

MT 9:38

There are. There’s a full range of gradations here. For research purposes, understandably, we concentrate on the most severe cases, but we get to know the people who adjust significantly, but would not be called patients who have major depression. It turns out that the exact same treatment approach, either preventive or compensatory applies regardless of how severe the symptoms get.

AB 10:25

I really want to hear what that treatment is. But first, I hope you can define some things for us. People hear the term Seasonal Affective Disorder or SAD. So can you define that for us? What is SAD? What does that mean?

MT 10:52

It’s describing a strong tendency to relapse into depression, or as you pointed out, into a blue mood, quite reliably as day length decreases in the fall, and the specific aspect of that is as sunrise gets later in the fall and winter. This affects us physiologically, and our circadian rhythms begin to slip later, because they are anchored to sunrise, that’s the way we are built. That’s the way the whole animal kingdom is built. So as we slip later, and have trouble waking up in the morning, and are dragging through the day, and are developing a set of other symptoms specifically focused on appetite, craving for carbohydrate rich foods, beginning to gain weight, as well as feeling really down, it all comes in as a package. And you’re going to see that in milder form throughout the population. So we have tracked population studies, people who don’t have any consciousness of dipping seasonally, but when you track them with logs and questionnaires, you see that their mood is falling, and they are gaining some weight. And they are having a little bit of feeling of excess sleepiness, and trouble getting going during the day. This applies throughout the population. But at a sub-threshold level, that doesn’t bother you. We see traces of it all over the place. It’s a quite normal cycle. But the magnitude of that cycle in about 5% of the population is quite remarkable and superior, and does require an intervention. Essentially, you’re dropping out of functional life for four or five months of the year. It’s interesting to compare it with other types of depression, when you don’t know when you’re going to crash, and you don’t know how long that episode is going to last. These are people who historically are strongly dependent on antidepressant meds. There’s a mystery aspect there because it is not so predictable. In the way people have SAD, even though they’re feeling rotten when it hits, they have an advantage because they know quite reliably when it’s going to come. And they have the faith that it’s gonna let up at a certain time. And this certain time varies plus or minus a couple of months from person to person, but any individual will be able to anticipate that — Oh, by this time next month, I’m going to feel like a human being again.

AB 14:58

What I hear you saying is that while the severe depression may be a much lower rate, it’s pretty normal for people to feel sluggish and snacky, and a little bit more sad, if you will, when it is darker, longer outside. I think the thing I noticed isn’t that I feel sad or sluggish in the winter, it’s when it starts to get light again, I noticed I feel better, and I didn’t notice I was feeling bad, right?

MT 15:30

That’s exactly my point. You have to recognize it, by looking at the contrast. Yeah. And in a case like yours, you’re part of that majority of the population who just travels with it. This is a part of normal life in the northern part of the world and in the temperate zone. You grin and bear it, you’re fully functional, you know, it’s going to resolve. And so that’s the way we’re built.

AB 16:08

I read that it’s actually very common, like you don’t have to live in Alaska, or in Canada, or even in Minnesota, to have this be part of your life. That happens even a little bit further south than that pretty reliably. Am I the only person who’s surprised by that?

MT 16:28

Well, here’s what the most recent research shows, and it’s based on sampling through the continental US. You find a little bit of it in the southern tier states, say 1% of the population will complain. I get phone calls from Southern Texas from Florida. For those few people who are affected, it looks just as bad. But you know, what’s happening is that the sunrise in Florida, it’s also getting later when winter comes, not as extreme, but it depends on the individual sensitivity. Then as we climb up the latitudes gradually from the southern states, up until the mid Middle States of the US, we see an orderly increase in the number of people who are experiencing this problem. When we get up, and now I’ll speak technically, when we get up to 38 degrees north latitude, that’s the level approximately of Washington DC, okay? It sort of gets as bad as it’s going to be farther north. In other words, there’s this incline in the lower half of the states up to the middle, and then it levels off, it ceilings out. So if you’re living in Washington, or New York, or New Hampshire or Minnesota, the likelihood that you’re going to feel this way, is pretty much the same. The sun has risen, the delay in sunrise has gone far enough to trigger the full syndrome.

AB 18:44

Hmm. Even if you’re not somebody who’s suffering from severe depression through this, and as you said earlier, requires intervention, there’s certainly ways to mitigate any of these feelings, right? Like you don’t have to live in contrast with your better, happier self for four months of the year, there are things you can do, correct?

MT 19:15

There are things you can do. But let me point out one feature that is not widely recognized, okay. It’s not 100% sure that you are going to slump or crash year after year after year without exception. It’s more of a statistical thing. It’s going to happen most years. And it’s even possible and perhaps this is dependent on life circumstances. It’s even possible to skip a year.

AB 20:01

So I’m guessing that other life circumstances, right, other problems such as COVID, for example, um, you know, isolation, other life circumstances like that are really weighing on you could all be part of a year that this is really a problem. Wow. Other years where, where you’re having a better time of it right? No COVID or whatever, it’s not as much of a problem. And for everyone listening, I apologize for my dogs barking, I am sure there’s something very terrifying right now such as the UPS man. But I imagined that those circumstances are things like that.

MT 20:53

It’s a good point. And the COVID case, which is so current, is the isolation indoors has exacerbated this problem currently. But there are many individual life circumstances like stress at work, and illnesses of other kinds, that can make it more likely that you’re going to crash that year. So this actually, the American Psychiatric Association, which establishes standards for the diagnosis of various disorders, will say that over your lifetime, seasonal episodes have to significantly outweigh non seasonal episodes. So simply because you skipped a year and are lucky, doesn’t mean that it’s not going to come back. Statistically, you have to expect that it will happen again. So it’s really important on a year by year basis, to look for signs that it is setting in. And, we’ve got a way to do that now. This is a more recent insight. There’s a certain point in this seasonal cycle, where you know, you have crashed, you’re out of it. But before that happens, for a month ahead, you may notice that that’s when you start having trouble waking up. That’s when you’ve switched from your healthy summer diet and are going for the Ben and Jerry’s and the pizzas and whatever is your thing. When that happens, it’s a signal that the depression is going to hit within three or four weeks.

AB 23:16

Also true for people who are not going to be clinically depressed to like, these are signs that everyone can look for?

MT 23:23

Of course, the population as a whole is gaining weight every winter, it’s just not as much, but everyone can look for this, having trouble getting out of that and getting to work on time. All of these are predictive symptoms that can tell you something bad is gonna happen within several weeks time. Now, if you pick up on it, come fall, come September, October, you can look for that rather than just ignore it when it happens and begin light therapy prophylactically. If you can be getting the light therapy before the mood plummets you can halve the entire episode or season. However, most people are not even thinking about these things. They’re coming on rather subtly in the fall. And by the time they’re ready to do something about it, they have crashed or they’re feeling as worse as they are going to see over that season. So I would say a majority of the people are waiting for the mood to go low before they are motivated to do something about it. That’s fine also, because within about, I’m really averaging here. But within about a week or so of daily light therapy when you wake up in the morning, for about 30 minutes, within about a week or so, even if you’ve become very depressed, it’s likely that the mood is gonna lift. And you’ll be back in your August, September state, and then in your July and August state. And then in your June and July state.

AB 25:48

How does one do this light therapy? Is this something you can do at home and does going outside in the daylight count as light therapy? Is there any way to do this outside?

MT 26:33

This is a good point. Time spent outdoors throughout the day has a mild mood lifting effect. But it’s not as potent and obvious as doing a structured light therapy regimen. As soon as you wake up, and you’re in the far north, and you’re still on a nine to five work schedule, you are waking up in the dark, right? By sitting at the breakfast table for 30 minutes with a bright light box which has been developed specifically for this application, you’re tricking the brain into thinking it’s in the alternate season. In the brain, the brain is interpreting that breakfast time exercise in the dark as the start of the morning. And your circadian rhythms which have slipped later are readjusting to their spring time stage. So this is actually the question, as you asked, it is a little bit wrong. It’s not — can you do light therapy at home? But essentially you must do it at home. Because its efficacy depends on doing it as soon as you wake up. And you’re not going to want to wait until lunchtime to do this on the job.

AB 28:23

Hmm. Interesting. Okay, so what is the cost of one of these lights? Where do you get one? Give us some practical insight on light therapy?

MT 28:37

Yeah, well. Everyone who has visited Amazon knows that there’s 150 different light boxes for sale with claims that they cure SAD. And virtually none of these have been tested clinically. And they are built in a way to sell as cheaply as possible. So the research field has developed criteria for an effective light box. And the typical commodity that you see for $39.95 on Amazon is a tiny little device, practically a handheld device, that claims to deliver 10,000 lux of light, which is an early morning outdoor light signal which has proved effective in clinical trials. But in order to get 10,000 lux of light from a gizmo like that, you have to hold it one or two inches from your eyes, intolerable, glaring, impossible, you must look away from that. An effective lightbox has a larger screen. And it may be one foot by one and a half feet in size, and it delivers 10,000 lux, but consider how we experience 10,000 lux outdoors. It’s coming from sky cover, it’s not coming from the ground, it’s not coming straight on from eye level. Effective light boxes have a set of legs that lift them off the table and tilt the box down toward your face in a simulation of sky cover. And that way, the eyes and the brain, and the body can experience that intensity therapeutically and comfortably at the same time. So the design of clinically effective lightboxes greatly contrasts with 90% of the devices that you see marketed right now. I would really encourage your listeners to examine the details of my argument here on the website of the Center for Environmental Therapeutics. It’s just a simple name, And there we go through all aspects of detecting the syndrome and treating it and selecting appropriate apparatus for it. The lightbox I’ve described is the main therapeutic intervention. But research has uncovered other methods as well, which are proving to be therapeutic without meds and we examine all of them on and then people can make a choice. Now if an individual is in fact plunging into a major depression, he or she should not actually grab a lightbox and begin self treatment without the monitoring of the clinician who can look for overreaction, who can or under reaction, and can help guide the course or, metaphorically, adjust the dose, to give an optimal effect without disturbance on the one hand, or at a level which isn’t going to help on the other hand. The people who fall into this middle range that we discussed who are experiencing the winter doldrums or the winter blues, you know, there’s enough information out there, expert information where you can read up on it and try it yourself. And I recommend the Center for Environmental Therapeutics website as being the most comprehensive source.

AB 34:06

Awesome. Can you give us an idea of the price point for a decent lightbox? Are we talking 100 bucks? Are we talking $150?

MT 34:19

$100-200. Averaging about $100.

AB 34:28

Cool. Well, we’ll obviously push people to go check out your website Just as you are looking at that, guys, just keep in mind, that’s the kind of price point you’re thinking about because if you are anything like me, you are doing exactly what Dr. Terman just said, which is heading into the Amazon machine and looking up your options.

MT 34:53

You’re right. The price itself is not the criteria. It’s the design All right, okay, it’s possible to find an expensive light that won’t do anything for you.

AB 35:07

I’m sure that’s very true. Now for those of us who also want to go outside, I would guess that the preferred time to head outside for, you know, natural light therapy. In addition to what we’re talking about here, from a light box, would be when the sun is the highest point in the sky. Is that accurate?

MT 35:37

You don’t have to wait that long. No, I used a magic number of 10,000 lux as having been proven to be fully clinically effective in clinical trials. And 10,000 lux is what we experience as you, for example, walk on the beach, half an hour after sunrise. But as you go toward noontime, depending on where you live, of course, the level of light can rise to 100,000 lux, or even higher than that. You’re going to get the full bang half an hour after sunrise, you don’t have to wait until lunchtime to do this. But of course, it will help to do that rather than that. The problem is it’s not simply the intensity, it is where your circadian clock has shifted between summer and winter. And you want to catch your inner clock as it is transitioning from its nighttime state to its daytime state. That’s going to happen before noon time for most people. Not for everybody, some people are going to be sleeping so much less that their clock has slipped hours and hours. They’re not waking up until noon time. And that’s morning for them. So we have to understand what is the physiological morning for each person. And there’s a quiz on the CET website that will tell you where your morning signal lies. It can advise you to do light therapy according to that resonance signal, which can differ by six hours from one person to the next person. This isn’t a trivial difference. So you want to find out where your rhythm is cycling, in order to determine the optimum time to get the signal. But even later than that during the day, it’s more helpful than not to be outdoors.

AB 38:34

I’m glad you brought up the quiz because I was 100% going to make my next question — but how do you know what your optimal time is? Because I mean, I’m an early morning riser. I’m an early bird. But given the option, I do not get up at 4am which is my normal alarm ringing, right? I wake up naturally sometime around, you know, 7, 6:30, or even 8 o’clock if I’m really tired. So, you know, it just varies widely if I have an alarm clock yelling at me or not. And I’m sure our listeners are very similar to that, although I pray that most of them don’t have to get up at 4am like I do.

MT 39:16

A lot of research has been done on this. And the gold standard method for measuring where a person’s circadian clock lies is by taking timed samples of blood samples and analyzing it for the level of the hormone melatonin in the bloodstream. During the middle of the day, we don’t make melatonin. It’s a nighttime hormone and at a certain point in the evening, it begins to rise. But for some people, it’s not going to rise until after midnight. Other people, it’s going to start to rise at 6:30 in the evening. And that’s the test for the position of the circadian clock. What we did is administer a set of questions about your timing preferences during the day — when would you prefer to exercise? When would you prefer to have meals? When would you prefer to go to bed and wake up if there were no job constraints? And by answering all these questions, we come up with a score, which it turns out, correlates very tightly with when you’re producing melatonin at night. So we don’t have to give a blood test to find out the right time of day for you, we can ask a set of questions, and it will then we can use that to infer your underlying circadian cycle and then scheduling the light accordingly.

AB 41:20

Wonderful. I will include a link for that in the podcast notes guys, so you can hop on over there and take that quiz and figure out when you should be doing this stuff and how to really amp up your mood. We focus here on Humans Outside on going outside, but I’ll tell you what, when you’re feeling sluggish, want to eat a lot of snacks and having a hard time getting out of bed in the morning, it’s a whole lot harder to go outside, you know. It might be good for you and it might be something you enjoy, but everything’s harder when you don’t feel good. So if that means using some light therapy inside to make going outside that much easier and be able to get out of that what you want to be able to get out of it, then by all means, get a light box and use that sucker every day. I am looking forward to taking the quiz myself and getting me a lightbox because I really, I was feeling this hard last year. And it wasn’t until mid February that I realized — Okay, you know what, like, this is a lot harder than it has been. You know, one of the ways we sort of self medicate here is in Alaska, people will tell you that they have to get out of the state in the middle of the winter to be able to feel better. It’s not a question of if, it’s a question of when, and we regularly go out of state in January to go to Florida or something just to spend a little time in the warmth and in the sun. And last year we waited an extra month. We had been going in early January and we went in mid February and it was too late. We needed to go earlier and I could feel the difference.

MT 43:02

Lesson learned.

AB 43:05

Hawaii was great, but man wouldn’t have been greater if I’d gone six weeks earlier.

MT 43:13

You can do light therapy at home and recreate the Florida situation with respect to your circadian cycle and your mood. There are other reasons for vacationing down there of course, yeah. You can make your own sunrise signal.

AB 43:36

Somehow I think that lightbox therapy at my kitchen table in Alaska will not be all that I was hoping for out of a beach vacation, but I’ll give it a try.

MT 43:49

You can be surprised because the switching mood is quite dramatic.

AB 43:56

Awesome. I will! I volunteer to test this and I will report back. Okay, well thank you so much for your time, Sir. You know, we sort of end our episodes pretty much the same way every time. We’ve been focused really hard on the science here and not so much the practicalities of going outside. So we won’t ask you about your favorite outdoor gear unless you have something very specific you want to mention. But we do like to talk to our guests sort of on the way out of imagining just, you know, hearing about an outdoor time that really was meaningful to you. So you can just walk us out as if we were there with you and describe that for us. So would you mind describing an outdoor moment that was really meaningful to you?

MT 44:44

A favorite feeling of mine, as I mentioned earlier in the program, is camping and sleeping in a tent, especially on the beach, where the filtered dawn comes through the canvas and you hear the crashing waves. And to me, that’s bliss. And I connect this to an experience I had with a patient at Columbia, quite dramatic. He was a Vietnam War vet. And he had a lifetime history of very, very difficult sleep. And we were trying the methods of light therapy to make him feel better. He said to me one time — I slept the best in my life, in a bunk, in a tent in Vietnam, with the war and the shooting going on all around me. The environment was extremely threatening and disruptive. And I slept a full night and I woke up to that beautiful image of the sunrise coming through. And, and he of course, was a light therapy responder as well. But despite the distractions, and the horror of the war going on around him, when he was out of his usual dark bedroom and sleeping in a tent, such as there was a natural sunrise bathing him in the morning, he felt like a new person. And to me that said it all.

AB 46:36

Thank you so much for joining us today on Humans Outside. We really appreciate your time and your expertise. And we’re sure all of our listeners are trotting right over to the website to take the quiz and see what we need to do for ourselves to get through the darker time of the year. Thank you.

MT 46:55

Thank you for a great interview.

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