The fall and winter months often signal the season of celebration and holidays. But for many, the darker, colder days herald another type of period: one of fatigue, lethargy and depression.<\/p>\n
Seasonal affective disorder, or SAD \u2014 a type of depression that occurs with the changing of the seasons \u2014 can affect up to 10 percent of people in the United States<\/a>, depending on where they live. Here are some of the most frequently asked questions about seasonal affective disorder, with answers from experts.<\/p>\n What exactly is seasonal affective disorder?<\/p>\n \u201cOne big, common misconception about SAD is that it\u2019s just the \u2018winter blues,\u2019\u201d said Kelly Rohan, a professor of psychological science and a clinical psychologist at the University of Vermont. When the days get grayer and colder and the holidays are around the corner, it\u2019s not unusual to experience temporary feelings of malaise, tiredness or stress. But seasonal affective disorder is much more serious \u2014 a form of clinical depression, Dr. Rohan said \u2014 with symptoms that can last longer, and that come and go with the seasons.<\/p>\n According to the National Institute of Mental Health<\/a>, you may have seasonal affective disorder if you experience certain symptoms that start and stop during specific months, and that occur for at least two consecutive years. These can include near-constant and daily feelings of depression, loss of interest in activities you used to enjoy, changes to your appetite or weight, sluggishness and low energy, trouble falling asleep or oversleeping during the day, or even thoughts of death or suicide.<\/p>\n Most people who have seasonal affective disorder have winter-pattern SAD (or winter depression), where symptoms begin in the late fall or early winter and go away during the spring and summer. But SAD can also occur during the spring and summer months<\/a>, called summer-pattern SAD (or summer depression).<\/p>\n SAD is much more common in women than it is in men, and in those living in the northern regions of the United States \u2014 like Alaska or New England \u2014 than in those living in Southern regions, like Florida. It can also sometimes run in families.<\/p>\n \u201cPeople may not appreciate how severely someone who has SAD is affected,\u201d said Dr. Paul Desan, a psychiatrist at the Yale School of Medicine. For some people, he added, \u201ctheir life just shuts down for half the year.\u201d<\/p>\n What causes seasonal affective disorder?<\/p>\n For those with winter SAD, shorter, darker days are what trigger depressive symptoms, Dr. Rohan said. But experts don\u2019t know exactly why this happens.<\/p>\n A leading theory has to do with a shift in the biological clock. Normally, the body produces melatonin at night, which helps promote sleep. When the levels of melatonin taper off as sunrise approaches, that helps people wake up. But if you have winter SAD, melatonin peaks later and lingers for longer into the morning, making it harder to wake up and leaving you fatigued and groggy. Because you don\u2019t reach peak wakefulness until later in the day, it\u2019s harder to fall asleep once evening comes \u2014 perpetuating a cycle of insomnia, inadequate sleep and fatigue, and exacerbating depressive symptoms.<\/p>\n Most people who are vulnerable to SAD are most likely always susceptible to feeling down, said Kathryn Roecklein, an associate professor of psychology at the University of Pittsburgh. But in the winter, light levels fall below a threshold and suddenly things are off balance.<\/p>\n There\u2019s also some evidence that the negative anticipation of shorter days \u2014 thinking, for instance, \u201cI just don\u2019t function well in the winter\u201d or \u201cI\u2019m going to start feeling poorly soon,\u201d Dr. Roecklein said \u2014 can combine with biological effects to create a self-fulfilling prophecy.<\/p>\n How long does seasonal depression last?<\/p>\n While this can vary from person to person, SAD symptoms can linger for quite a while \u2014 up to five months for some, said Dr. Lily Yan, a professor of psychology and neuroscience at Michigan State University.<\/p>\n Most people who have winter SAD will begin noticing symptoms between October and November, Dr. Rohan said. But if you live in parts of the country where people are more susceptible, you may notice them earlier in the fall. Stressful life events, like work instability or grieving a loved one, might also kick off depressive episodes earlier than usual.<\/p>\n The most severe symptoms tend to occur in January and February, Dr. Yan said. Some experts think this happens because of the accumulated effects of SAD over time, she said. The longer you have symptoms, the worse they get. But people tend to start feeling better once spring and early summer roll around.<\/p>\n Symptoms of summer-pattern SAD, which is much less common, tend to start in the spring and end around the beginning of fall.<\/p>\n What are the best ways to manage seasonal depression?<\/p>\n The good news, experts say, is that there are several evidence-backed ways to find relief.<\/p>\n Bright light therapy<\/p>\n \u201cBright light treatment first thing in the morning dramatically improves the vast majority of people with seasonal affective disorder,\u201d Dr. Desan said. This involves sitting in front of a light therapy box, which mimics outdoor light, for about 30 minutes every day right when you wake up, preferably early in the morning. This should stimulate your body to produce the right hormones to increase your wakefulness and alertness to get you through the day, Dr. Desan said.<\/p>\n Just make sure to use it properly. If you don\u2019t use it early enough, it may not work; and if you use it too late in the day, it could exacerbate insomnia, Dr. Rohan said. Most experts recommend using light therapy lamps before 8 a.m.<\/p>\n Plenty of lamps out there won\u2019t do you any good, Dr. Desan said. When searching for a light therapy lamp, you want one that advertises 10,000 lux brightness \u2014 the equivalent of a bright summer morning. A good light therapy lamp should also be \u201cfull spectrum,\u201d he said, meaning it emits light that closely mimics natural morning sunlight. Unfortunately, it\u2019s challenging to know exactly what you\u2019re getting, since light therapy lamps aren\u2019t regulated. To help guide buyers, Dr. Desan\u2019s lab at Yale has clinically vetted a number of lamps, and listed its recommendations<\/a> on its website.<\/p>\n If you think you have seasonal affective disorder, consult with a therapist or psychiatrist before deciding on a treatment plan. They can offer guidance on the best plan for you \u2014 and if it involves bright light therapy, they can teach you how to do it properly, Dr. Rohan added.<\/p>\n Cognitive behavioral therapy (C.B.T.)<\/p>\n C.B.T., a form of talk therapy that aims to shift faulty or unhelpful ways of thinking, can also be beneficial, Dr. Rohan said. If you say things like, \u201cI hate winter\u201d during a session, she said, the therapist will try to reposition those negative thoughts. \u201cEven if we could take it down a notch to, \u2018I prefer summer to winter,\u2019\u201d she said, that can result in a big shift in symptoms and mood.<\/p>\n Because cognitive behavioral therapy for SAD involves retraining your negative associations with darker months, it is the only treatment that could have long term benefits after doing it just once, Dr. Roecklein said. \u201cIt works in the winter when that person comes in for a treatment,\u201d she said, \u201cbut then it also protects them from depression the next winter and the winter after that.\u201d<\/p>\n Antidepressant medications<\/p>\n Seasonal depression can also be treated with antidepressant medications, like the selective serotonin reuptake inhibitors fluoxetine (Prozac), citalopram (Celexa), sertraline (Zoloft), paroxetine (Paxil) and escitalopram (Lexapro).<\/p>\n