Seasonal affective disorder affects millions of people. Here are the symptoms

Woman looking out of window at sunset
About 1 in 20 people have seasonal affective disorder.
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For some, autumn’s return is coupled with fatigue, feelings of loneliness, and even hopelessness. A shift in mood that coincides with the change of seasons may signal seasonal affective disorder (SAD). About 10 million Americans experience SAD, which is a form of depression that usually affects people from mid to late fall through the early days of spring. 

“The most common misconception is that it is ‘just’ winter blues and not that big of a deal,” says Dr. Jeff Temple, licensed psychologist and professor at the University of Texas Medical Branch. “On the contrary, it impacts millions of Americans with symptoms consistent with major depression.”

SAD may be caused by factors outside of your control, but you don’t need to wait until the first signs of spring to feel better again. Here, experts suggest some simple changes that may help.

What are the symptoms of SAD? 

It may be difficult to tell whether you’re experiencing SAD because the symptoms mirror depression more generally and also may resemble some winter “hibernation” behaviors, says Temple. The main difference is that SAD symptoms usually subside when the spring arrives. Symptoms include:

  • having less energy
  • weight gain
  • less interest in doing things you enjoy
  • trouble sleeping or oversleeping
  • changes in eating habits
  • feelings of hopelessness or worthlessness
  • withdrawal from your routine

At the onset of SAD, people may also have more food cravings and sleep later. 

What causes SAD?

Less daylight can cause a drop in serotonin, the hormone that regulates mood. Additionally, melatonin, released before we sleep, is triggered by darkness and can shift in response to fewer daylight hours leaving us feeling sleepy earlier, which can affect our mood and mental health. Some people may be prone to the effects of these shifts more than others. 

Colder temperatures can also lead us to limit outdoor time—and reduced exposure to sunlight means less vitamin D, which boosts serotonin and energy.

Who is more likely to experience SAD? 

Women are four times more likely than men to have this type of depression, in part due to their hormone makeup, which experts speculate makes them more sensitive to the effects of limited sunlight.

Those who are already diagnosed with mental health issues, including depression, bipolar disorder, and anxiety, are more prone to SAD than those who are not. 

SAD is also more common for people who live in areas with seasonal variation or live far from the equator where sunlight during winter months is limited, but it’s still not clear why some people are affected by the changing seasons while others remain unfazed. 

What can you do about it? 

Light exposure is the primary tool to treat SAD, and Temple says 30 to 45 minutes of exposure to a lightbox (a tool that mimics bright sunlight indoors) daily can help reduce the symptoms of SAD and make you feel less sleepy. Many retailers and online stores carry lightboxes. Look for ones that have 10,000 lux for optimal benefits. 

Typical remedies for depression like medication, talk therapy, and cognitive behavioral therapy can help too. 

It’s also important to establish a sleep routine where you wind down calmly, limit distractions, and go to bed and wake up around the same time each night.

You can prioritize getting as much sunlight during the day, and right when you wake up, to kick-start your day and help regulate your hormones. 

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