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The Dose Transcript for November 23, 2023

Host: Brian Goldman

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BRIAN GOLDMAN: Hi, I'm Dr. Brian Goldman. Welcome to The Dose. Well, we've entered that time of year when sunlight is hard to come by. Pretty much every November, my brain stops firing on all cylinders right about now. My mood begins to tank, and I feel a lot more tired. If like me, you are prone to seasonal depression or perhaps the winter blues, this can be a tough time of year. But there are ways to deal with it and maybe even prevent some of the symptoms. So this week, we are asking, how can I take care of my mental health through the dark months? Hi, Raymond. Welcome to The Dose.

RAYMOND LAM: Hi, Brian. Pleasure to be here.

BRIAN GOLDMAN: It's good to talk to you too. Is this something that affects you? You know, I've just confessed that it affects me. But does this in any way affect you?

RAYMOND LAM: Well, actually, it's interesting that I'm actually not very seasonal, unlike many researchers in the field. And so for me, you know, I prefer summer, but I don't really notice many changes in the wintertime.

BRIAN GOLDMAN: Okay. So yeah, well, unfortunately, I am seasonal and you treat people. You advise people who have seasonal depression, seasonal affective disorder, which is why we want to talk to you. But before we begin, can you give us a hi, my name is? Tell us what you do and where you do it. Just adlib.

RAYMOND LAM: Sure. I'm Dr. Raymond Lam from the University of British Columbia in Vancouver, Canada, and I'm a psychiatrist. And so I see patients with primarily depression and difficult to treat depression. And I've been a researcher at the University of British Columbia for decades now studying seasonal depression and light therapy and among other topics in depression.

BRIAN GOLDMAN: Then you're just the right person to speak to. So let's begin by getting you to define what they mean by seasonal depression.

RAYMOND LAM: Sure. Well, you know, people have heard the term SAD or seasonal affective disorder. And affective is just a psychiatric term for mood. So these are people who have clinical depressions, but only during the wintertime. So they start getting depressed around this time, late fall or early winter. They're clinically depressed through the winter months. And then by spring and summer, they are actually feeling better. And in the summertime, they're feeling well. So this is a pattern that happens to them regularly where they only have depressions during the winter. So we call it winter depression or seasonal depression. There are other types of seasonal depressions. There's a summer depression, but they're much less common and less well studied. So when we talk about seasonal depression, we usually talk about winter depression.

BRIAN GOLDMAN: So one of the things, Raymond, that people, you know, people like us love to do is name and rename and keep changing the names for disorders. So is seasonal depression and seasonal affective disorder, are they the same things?

RAYMOND LAM: They are because we use the term depression, you know, many ways. But I've talked about a clinical depression. And so that's what we define as people who have signs and symptoms of depression to the point where it's really interfering with their functioning. And so this is a clinical diagnosis. A seasonal depression is a subtype of major depressive disorder, which is the term we use for, you know, for clinical depression. And so these are serious conditions. But we also think about seasonality as a dimension or a spectrum. And so it does go to, you know, people like me who aren't particularly seasonal or don't notice many changes to people who have, you know, what we call a winter blues where they have a lot of the same symptoms of winter depression, but not to the point where it's really interfering significantly with their functioning. And some of those symptoms relate to, you know, symptoms, not just low mood or feeling sad, but more physical symptoms like reduced energy and fatigue, increased need for sleep and having trouble getting up in the morning, increased appetite and weight gain in the wintertime, which, you know, sound a lot like kind of hibernation type symptoms, but hibernation is actually a very complex condition in animal behaviour. And so it's not quite like that biologically, but certainly, you know, figuratively, it looks a lot like hibernation.

BRIAN GOLDMAN: Are there biochemical similarities between hibernation and the winter blues?

RAYMOND LAM: No, unfortunately not. That's why I say it's not a particularly good biological parallel. But, you know, people think of hibernation as that kind of a type of symptomatology where you want to sleep, you want to, you know, you need to eat and gain weight and you're very sluggish during the wintertime.

BRIAN GOLDMAN: It kind of made me wonder if I should be seeking a den to kind of hang out in for several months. But to do that, I'd have to sign off work.

RAYMOND LAM: Yes. Unfortunately, people with SAD, you know, they feel like if I could only get enough sleep, I'd feel better. But in fact, that's not the case. They just feel more tired the more sleep that they have.

BRIAN GOLDMAN: So what are the main symptoms of seasonal depression? You've started to mention them. You mentioned mood changes and also energy changes. But can you give us that longer list?

RAYMOND LAM: Yes. So there are mood changes, the energy changes, there are the sleep changes that I've mentioned in terms of increased need for sleep. There's the appetite changes, carbohydrate craving particularly in the wintertime, and there are also cognitive changes. So by that, I mean problems with concentration, thinking, memory, organization skills, things like that that really affect people with depression. And then, you know, at the kind of more serious end, very common in people with depression, feelings of hopelessness like life isn't worth living. Even suicidal thoughts can be present. And the symptoms for winter depression are a little different than other types of depression because, you know, non-seasonal depressions more commonly have insomnia rather than increased sleeping, and they typically have reduced appetite rather than increased appetite. So there are some differences between common symptoms of winter depression versus other non-seasonal depressions.

BRIAN GOLDMAN: You know, it's interesting. You know, as I've said before on The Dose, I'm a chronic insomniac and I have trouble staying asleep. I tend to wake up several times in the middle of the night, particularly around 4 a.m., 4:30 a.m., and I can't get back to sleep. And I've noticed that since it's gotten darker, I'm sleeping later. What do we know about the causes of seasonal depression? Obviously, exposure to light has something to do with it.

RAYMOND LAM: Yes. And I think that's, you know, the key thing is that what we understand about seasonal winter depression is that it is related to the changing levels of daylight that's available in the winter. You know, the days are shorter in the winter compared to the summer. There's less light, particularly in the morning, where it's important for our seasonal rhythms. And so one of the major theories of seasonal depression is that it is a disturbance of the biological clock that's in the brain, because we know that light is the strongest synchronizer of that biological clock. So SAD may be like a form of jetlag where there's a disconnect between the internal clock and the external environment, that the changing levels of light from summer to winter.

BRIAN GOLDMAN: Got it. There are also some theories that involve brain chemicals like serotonin.

RAYMOND LAM: Yeah, absolutely. And our studies and others have, you know, shown that there are disturbances in serotonin. Serotonin of all the neurotransmitters involved in mood is one that clearly has a seasonal pattern of metabolism so that we do get lowest levels of serotonin in the brain in the winter and spring, early spring, and the highest levels in the summer and fall. And so it's a neurotransmitter of interest. And there are some studies showing that, you know, light may directly affect serotonin levels. But of course, everything in the brain is connected. And so there are also relationships between the biological clock and serotonin.

BRIAN GOLDMAN: And so it's believed that the changes in exposure to ambient light would be responsible for the changes in serotonin levels that we see that are seasonal.

RAYMOND LAM: Yes. Yes, that's one of the theories.

BRIAN GOLDMAN: Oh, okay. So the $64,000 question is do people who live in equatorial zones, for instance, have more stable levels of serotonin and are less likely to have seasonal affective disorder compared to us who, you know, people like us who live well into the northern hemisphere?

RAYMOND LAM: Yeah. So they don't show as much variation in terms of the serotonin levels, and they certainly don't have as much of the winter depression. So again, people have looked at all sorts of factors, you know, temperature, snowfall, amount of cloud cover, and the only thing that is related to how prevalent that SAD is is latitude. And so as you go farther north or farther south in the southern hemisphere, you get increasing rates of winter depression to about a maximum around 50 degrees latitude.

BRIAN GOLDMAN: Okay. I know this is a kind of… a kind of… this results in a fairly rapid change all of a sudden. I'm talking about the change from daylight saving time to standard time. Does that play any role? Does that have any impact on delaying the onset of seasonal disorders because it provides more light in the early hours of the morning?

RAYMOND LAM: Yes. Well, as I said in this theory, SAD is like a form of jetlag. So any change in terms of the clock time will have effects on people with winter depression. And the clock changes we know are bad anyway. We shouldn't be switching our clocks in the spring and in the fall. But standard time is clearly better for people with winter depression, and that's because the clock is more the natural rhythm of the daylight and the bright light. And so it's a better synchronizer for everyone, but especially with people with winter depression. We think it's the dawn signal, the early morning light that's most important for our circadian rhythms and for people with SAD. And that's one reason why when we talk about treatment, that we use bright light therapy in the morning around 7 a.m. when it's not ordinarily light out in the winter.

BRIAN GOLDMAN: Great. So you have led us into what I think everybody wants to know about, and that is treatment. So what are the best treatments for seasonal depression?

RAYMOND LAM: Well, it's almost been 40 years now since bright light therapy was first described as being effective for people with winter depression. And it made a lot of sense because, you know, it seems like they weren't getting enough light because of the shorter winter days. And by applying bright light, they would get better. And it's very clear now that bright light is an effective treatment for people with winter depression. About 60 to 70% of people get a lot of relief from using a light box or a light device for about 30 minutes a day in the early morning time. And it's a rapid effect, so people notice the difference within a week or two. Unfortunately, when they stop using lights, they also notice the symptoms coming back in about a week or two. And so it isn't a one off treatment. You have to continue using it on a daily basis. And people usually use it through the winter until the time there are normal spring and summer improvement, and then they can stop using the lights in the summertime.

BRIAN GOLDMAN: There are all kinds of different devices. What do you recommend? What are the key ingredients of successful light therapy?

RAYMOND LAM: Well, we think the key ingredient is really the intensity of light that we measure with a measurement called lux, l-u-x, a measure of illumination. And we use 10,000 lux for the light boxes. And so then you only need 30 minutes of light exposure. We understand the effect is through the eyes. So people have to be awake with their eyes open, but they don't have to be staring at the light while they're using it. And so you can be reading or eating breakfast or looking at your screens during that time, but it's not risking exposure. And so ultraviolet wavelengths are not helpful for the antidepressant effect. And so most of the light devices have UV filters to block out harmful ultraviolet wavelengths. And just to illustrate what 10,000 lux is, for comparison, inside your living room at night when you have living room lighting is less than 100 lux. A very bright office is about 400, maybe 500 lux, but outdoors on a cloudy day in the wintertime is probably 3 to 5000 lux, and outdoors on a sunny day in the winter is 50 to 100,000 lux or higher. So you can see that 10,000 lux is somewhere in between kind of outdoor light, bright outdoor light and indoor light. And you can't really get indoor light up to the 10,000 lux intensity without using a light device.

BRIAN GOLDMAN: Where do you get these devices?

RAYMOND LAM: Well, they're available in a lot of places now, which is great. They're widely available. You can buy them. Many pharmacies carry them. Costco had some light devices. You can order them online. Our website, ubcsad, all one word, .ca., has a lot of recommendations. We don't… I have no disclosures. I have no financial relationships with any light products, but we do give recommendations for, you know, how to get a light, instructions for using it, etc. I think the key, though, is that you have to be careful because the lux rating, the intensity rating varies with the distance to the light source. So every light device has a distance where you have to set in order to get that 10,000 lux. And the smaller the device, the closer it has to be to your eyes. So some of the small, cheap devices, we don't recommend because you basically have to be four inches from your eyes, which is, you know, too close. And that's why we recommend some of the larger ones that sit on your desktop, about the size of a TV monitor.

BRIAN GOLDMAN: There are side effects that you can experience with light therapy. Can you list some of those?

RAYMOND LAM: There are some side effects, but they're generally mild. They're generally self-limited. They generally don't stop people from using the light and they're less than with medications. And so those side effects are actually similar to the antidepressant medications. So, you know, sometimes, people feel a bit nauseous. There's a mild headache. There's some glare or eye strain that might be involved. And sometimes, the light has an energizing effect, which is helpful for a lot of people because they're having trouble with energy. But, you know, for others, it's kind of activating. It's over-activating. It makes them feel a bit agitated. And in that case, we usually suggest, you know, sitting a bit farther back from the light so that you get less intensity of the light exposure. There's a small risk in people who have a vulnerability to bipolar disorder that it could again, that activating effect might make them too energized and too speedy. And so that's something to look out for for people with bipolar conditions.

BRIAN GOLDMAN: Often, when we think of light and wintertime, we think about vitamin D Is vitamin D a treatment for seasonal depression?

RAYMOND LAM: Well, people have looked a lot at vitamin D. Some small studies suggested that vitamin D might be helpful for winter depression. But now, we have some large studies and it doesn't look like it really does much for depression. Now, vitamin D is low in the winter in many people because, again, it's activated by ultraviolet rays. And so, you know, the light devices we use, you know, won't increase vitamin D, and people can't get a tan, unfortunately, while they're under the lights. Maybe that's good. Tans aren’t good for you. So we don’t recommend vitamin D for depression, but vitamin D is good for other things. And so I think, you know, vitamin D supplementation is usually a good idea for many people in the northern hemisphere.

BRIAN GOLDMAN: What about other kinds of therapies, other kinds of treatments that can help with seasonal mood disorders?

RAYMOND LAM: Well, one of the, you know, I won't say disappointing because it is a good treatment. One of the disappointing things about light therapy for us researchers is that we thought it was specific for winter depression because it made a lot of sense. But now, our studies and many others have shown that light therapy is actually also effective for non-seasonal depression. And so whatever time of the year that you use it, even in the summertime. And so it is one of those things that our treatments are not very specific for depression, and that's why other treatments for non-seasonal depression are actually helpful for winter depression as well. And that includes things like exercise, includes antidepressant medications, particularly the serotonergic medications, SSRIs, and also psychotherapy. So that cognitive behaviour therapy we know is a very effective treatment for depression in general, and it also seems to be helpful for people with winter depression.

BRIAN GOLDMAN: You mentioned cognitive behaviour therapy, CBT. How does that work? What are you trying to accomplish with that?

RAYMOND LAM: So cognitive behaviour therapy looks at dealing with some of the negative cognitions, the negative thinking patterns that people with depression get into. You know, feeling that nothing's going well, looking at the, you know, the dark side of things, the negative side of things rather than positive, catastrophizing from, you know, small mistakes. And by identifying and using strategies to deal with those negative thoughts and behaviours, people feel better from their depression. So similar for winter depression, there are a lot of kind of misconstrued, well, not misconstrued, negative thoughts about winter, right? People say, oh, I always get depressed in the winter. You know, I'm never going to be able to do anything. I can't get up, you know, at all. And by kind of addressing some of those negative thoughts and looking at strategies like, you know, set in your bedroom lights on a timer so that you awaken into light rather than into darkness, you know, can be very helpful in terms of getting past some of those negative cognitions and feeling better and doing better during the winter.

BRIAN GOLDMAN: You've talked about some things that people can do on their own. At what point should they be seeking medical attention, attention from their health care provider because these symptoms are becoming more serious?

RAYMOND LAM: Yeah. So I should have mentioned as well while we were talking about that that these treatments are also helpful for people with winter blues. So the milder form of seasonality, who don't necessarily have a clinical depression, but who may have particularly the physical symptoms associated with SAD. And so light therapy is very helpful for those people as well and something that we recommend that many people use to ward off the winter blues. But I think that, you know, if you're having these symptoms, again, to the point where it's interfering with your functioning, where you're having trouble at work, where you're having trouble with your relationships, when you're not doing the things that you enjoy doing anymore, I think that's the time to, you know, get checked out. First step is usually with your family physician to check and make sure there aren't other things going on that might explain it, but also to, you know, look at treatments for winter depression if that's the case.

BRIAN GOLDMAN: I guess the best news of all is that for most people, it will pass.

RAYMOND LAM: Yes. And that's one of the things that's more hopeful in people with winter depression compared to other types of depression, because of course, with other types of depression, you never know how long it's going to last. And, you know, maybe weeks and maybe months. For some people, years. But for winter depression, they know that things are going to get better, you know, by springtime. It’s still obviously, you know, interfering a lot with their functioning during that time, but there isn't quite the same degree of, you know, kind of hopelessness that is often apparent in people with non-seasonal depression.

BRIAN GOLDMAN: And that's a hopeful note on which to end our conversation. Dr. Raymond Lam, thank you so much for speaking with me on The Dose.

RAYMOND LAM: Oh, it's been great to be here. Thanks, Brian.

BRIAN GOLDMAN: Dr. Raymond Lam is a professor of psychiatry at UBC and an expert and researcher in seasonal mood disorders. Here's your dose of smart advice. Shorter days and less sunlight can trigger feelings of sadness and other symptoms. While many people experience the winter blues, some may have seasonal affective disorder, which is a form of depression. The Canadian Psychological Association says roughly 15% of Canadians will have at least one mild episode of seasonal affective disorder in their lifetime, and 2 to 3% will have more severe episodes. Women are more likely to have seasonal affective disorder, as are younger people. The condition is common in people who live at latitudes where winter sun is scarce. Symptoms typically begin in late fall or early winter and lessen by spring and summer. Seasonal affective disorder is triggered by a decrease in early morning sunlight, which affects your biological clock, which in turn controls sleep wake patterns. The lack of morning sunlight also affects the level of serotonin in the brain. The symptoms include irritability, low energy and feeling tired or heavy much of the day. You may not feel rested even after sleeping all night. You may also crave dietary carbs and fats and be prone to weight gain. Exposure to natural light can be very helpful, especially within one hour of waking up. You can sit beside a window with open blinds. Better still, take frequent walks outside with proper UV protection. Artificial light therapy where you sit in front of a special lamp or light box for 30 minutes a day can be an effective way to improve symptoms. It's been shown to be particularly helpful when combined with antidepressants. For the treatment to be effective, you need a bright light source, meaning 10,000 lux. Potential side effects of light therapy, which tend to be mild, include eyestrain, agitation, headaches and nausea. Consult with your health care provider before purchasing a lightbox for home use. Vitamin D does not relieve the symptoms of seasonal depression, but has many other health benefits. Other things that help include regular exercise and a healthy diet. The most widely recommended psychotherapy for seasonal affective disorder is cognitive behavioural therapy or CBT. Antidepressants may be prescribed when symptoms are more severe and more persistent. See your health care provider if your symptoms are affecting your relationships or your ability to function at work. If you have topics you'd like discussed or questions answered, our email address is thedose@cbc.ca. If you like this episode, please give us a rating and review wherever you listen. This edition of The Dose was produced by Isabelle Gallant. Our senior producer is Colleen Ross. The Dose wants you to be better informed about your health. If you're looking for medical advice, see your health care provider. I'm Dr. Brian Goldman. Until your next dose.

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How can I take care of my mental health through the dark months? - Transcript

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