What to know about seasonal affective disorder

As the air gets colder and the sun goes down earlier, some people find themselves less inclined to complete their daily tasks. Although it is normal to feel a bit more bummed than usual during these months, it's imperative to know the difference between being in a funk and having a disorder, experts say.

Seasonal affective disorder (SAD) is a form of depression that happens during periods of less sunlight and shorter days, according to John Hopkins Medicine. The disorder is linked to a “chemical change in the brain” and usually results in the body making more melatonin, the sleep hormone, because it's dark outside earlier.

Due to fewer hours of sunlight, a person's internal clock might be thrown off during winter-onset seasonal affective disorder, according to Mayo Clinic. Levels of melatonin are disrupted in the body, changing sleep patterns, and levels of serotonin, the hormone that affects mood, drop.

About 5% of adults in the United States have seasonal affective disorder, according to the Cleveland Clinic. The disorder tends to affect women more than men.

“I think people try to sugarcoat it. Seasonal affective disorder is much more linked to daylight hours. While there's a lot of similarities between that and depression, what might be driving the bus for seasonal affective disorder could be a little different,” Joseph F. McGuire, associate professor of psychiatry and behavioral sciences for John Hopkins Medicine, told McClatchy News.

As it gets colder, a lot of people tend to have a bit of a lower mood, McGuire said. They want to stay home and get a little “snuggly.”

But for people with SAD, it's more than just not wanting to go outside or spend time with friends. It's a biological change.

The symptoms of seasonal affective disorder have a lot of overlap with those of depression, such as being in a low mood and not being able to get enjoyment out of the things that would normally bring pleasure, Mimi Winsberg, psychiatrist and chief medical officer at Brightside Health, told McClatchy News.

“Depression can usually present itself in changes of sleep. That change would either be sleeping too much or too little. With seasonal affective disorder, we tend to see the need to sleep more than usual. We tend to see more sleep, less energy and a tendency towards weight gain and craving carbs. It's kind of a hibernation pattern,” she said.

The disorder is “characterized by its recurrent seasonal pattern,” according to the National Institute of Mental Health. Symptoms tend to last about four to five months per year, most commonly in the winter months.

Symptoms of seasonal affective disorder can mimic depression, according to the Mayo Clinic:

• Feeling sad or down most of the day, almost every day

• “Having low energy and feeling sluggish”

• “Having difficulty concentrating”

• “Feeling hopeless, worthless or guilty”

A professional will typically wait to see if someone has symptoms for at least two winters before diagnosing them, Winsberg said.

Both McGuire and Winsberg told McClatchy News that the first and most important step to help with seasonal affective disorder is to seek help.

Winsberg said it should be looked at like getting any other form of medical treatment.

Some people don't even know where to start if they want to seek treatment. They might not know the process of it all, and it can be intimidating, McGuire said.

“The first step is doing some research to find a treatment near you. A lot of sites offer free online evaluations,” McGuire added. “What I would hate is for someone to feel depressed and not know there is support and help out there.”