Last year, around early November, Megan Phillips couldn't get out of bed or wash her dishes. It felt like she couldn't do anything constructive. The 32-year-old Vancouverite had never been this sluggish, and a heavy depression began to settle in.
"When I felt that weather change," she said in an interview, "I felt a palpable shift in my mental health."
Phillips said she suffers from seasonal affective disorder, commonly known as SAD. SAD sufferers report experiencing temporary depression beginning in the fall and lasting through winter. It's long been believed to be a malady triggered by lower levels of sunlight, with symptoms that range from excessive sleeping to irritation and loss of appetite. The condition may affect as many as six percent of Americans, numbers that are presumably about the same in Canada.
"It's a very broadly held cultural belief that the seasons and moods are correlated"
But numerous studies have emerged to counter the claim that the changing seasons or weather patterns have anything to do with people feeling more depressed during winter months. While depression is all too real for those who suffer from it, some researchers say the debate still isn't closed on whether SAD itself is an actual thing.
In fact, it may be chalked up to a perception that depression worsens during winter months, as opposed to a diagnosable illness backed by hard evidence, emerging research contends.
In January 2016, a study published in Clinical Psychological Science concluded that "the idea of seasonal depression may be strongly rooted in folk psychology, but it is not supported by objective data."
In that study, using data collected in 2006 as part of the Behavioral Risk Factor Surveillance System (BRFSS), a phone-based health survey conducted annually in the US, researchers from Auburn University at Montgomery in Alabama found that respondents who took the survey in the winter months, or at times of lower sunlight exposure, didn't report having noticeably higher levels of depressive symptoms than those who responded to the survey at other times of the year.
"It's a very broadly held cultural belief that the seasons and moods are correlated, and when you ask someone in the street when they feel worst, they'll say winter," study co-author Steven LoBello told me. "One of the things going on is there could be a drop in mood during winter…but a drop in mood is not depression."
Ask any self-proclaimed SAD sufferer about the main cause for their seasonal depression, and you'll often hear replies related to lack of sunlight, due to the season's shorter days. But LoBello pointed to a 2008 European study blasting the theory that changes in sunlight provoke seasonal depression: it found "the population of Northern Norway, living without sun for two winter months, does not spontaneously complain about depression during the dark period."
Much of the research on SAD has used the Seasonal Pattern Assessment Questionnaire (SPAQ) for case identification, which act as a self-assessment checklist. But SPAQ's validity in the SAD body of research has come into question.
One of LoBello's criticisms of SPAQ is that it requires respondents to recall their mood variations over at least one year, possibly longer, which respondents may not be able to do very reliably.
In their study, LoBello's team harnessed the BRFSS replies because respondents reported depression within two weeks of the survey, as opposed to a year.
Not everyone is convinced that it's time to dismiss SAD out-of-hand. Katy Kamkar, a psychologist at the Centre for Addiction and Mental Health in Toronto, said, "Keep in mind, this survey is anonymous and self-reported. For any mental health condition, we need to continue to do studies to further understand it and its treatment."
LoBello countered that people might be more truthful about mental health conditions on an anonymous survey, where they don't have to reveal their identities.
Several studies do suggest that SAD is a real illness. In one, published in 2015 in Current Biology, researchers described how they'd found a region of the brain that seems to contribute to certain seasonal light cycle effects that might drive SAD, in mice.
As scientists continue to untangle all this, Golbon Maltaji, a 31-year-old Ottawa resident, says she doesn't need a doctor to diagnose her with SAD. She recognizes that she suffers from depression during winter months, which she noticed years ago when she moved to Canada from Iran.
"The point is it really doesn't matter if people think SAD is a myth or not," she said. "What matters is that your body, your intellect is telling you something about you, about your environment."
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