As the days grow shorter and the nights longer, many Americans find themselves grappling with the "winter blues."

A recent poll from the American Psychiatric Association sheds light on this widespread phenomenon, revealing that two in five Americans experience a decline in mood during the winter months. The poll also found that 41% of Americans reported sleeping more in winter, 28% said they experienced increased fatigue, and 27% said they felt depressed.

Those in the Midwest — where the winter months can be particularly long and harsh — felt the most pronounced impact.

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"There are several things that you can do that might be helpful, including trying as much as possible to stay into your routines," said Kelly Rohan, a psychology researcher at the University of Vermont. "Try to get outside as much as possible. There's plenty of light to be had in the wintertime. You just have to dress appropriately."

An estimated 5% of American adults suffer from "Seasonal Affective Disorder" (SAD), a condition characterized by serious mood changes that persist for at least two weeks.

Symptoms of SAD include persistent sadness, loss of interest in activities, changes in appetite, feelings of worthlessness or guilt, difficulty thinking or concentrating, and thoughts of death or suicide. The most challenging months for those with SAD tend to be January and February.

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For those experiencing more severe symptoms, experts recommend antidepressants, bright light therapy, and cognitive behavioral talk therapy. Most importantly, experts stress the importance of seeking out help from medical professionals.

"It really is a good idea to have a conversation with your doctor and find out if you really do have seasonal affective disorder and how it can best be treated," Rohan notes.

If you're struggling with seasonal mood changes or having thoughts of suicide, the Suicide and Crisis Lifeline is available 24/7 by dialing 988 or by texting "HOME" to the Crisis Text Line at 741741.