Seasonal affective disorder isn't just the 'winter blues.' 6 myths about SAD that experts want to set straight.

Two people seen sitting at a narrow table with coffee mugs through a cafe window, with one resting her head on her folded arms.
What distinguishes seasonal affective disorder from the so-called winter blues — and what to do about it. (Getty Creative)

December is Seasonal Depression Awareness Month, and it's little surprise why. The days are short (the winter solstice on Dec. 21 is the shortest day of the year, in fact), the weather is cold and bleak, and by the time most folks finish work for the day, it's already dark out.

These seasonal changes can be a nuisance for some people, but for others — about 5% of American adults and even some children — they can also bring on a form of depression known as seasonal affective disorder, or SAD. Signs of SAD include having low energy, sleeping too much, craving carbohydrates or experiencing other appetite changes, avoiding socialization and feeling sad and listless for much of the day.

Because it's not uncommon for people to feel somewhat low during the colder months, SAD is often confused for the "winter blues." It's also often believed to be limited to the winter months, but some people experience SAD during the spring and summer. These are just two misconceptions about the mental health condition that can cause some people who suffer from SAD to shrug off their symptoms and not seek out the help they need. Ahead, experts break down what else we're getting wrong about SAD — and why it's important to understand what it can look like.

Many people might feel dejected when the sun starts going down at 4 p.m. and it's too cold and dark out to do some of the things we love. However, not all of these people have SAD, which is a diagnosable mental health condition that can affect many aspects of a person's life.

“While it’s true that many people feel a dip in mood during darker winter months, SAD goes beyond a typical ‘winter slump,’” Lauren Auer, a certified trauma professional who both treats clients with SAD and experiences it herself, tells Yahoo Life. “It’s a clinical form of depression with a real neurological basis.”

If you have SAD, you won't merely feel "meh" about the change in seasons. You'll notice disruptions to your mood, energy level, sleep, appetite, social habits and more, which should be discussed with a health care provider.

Many people associate SAD with the late fall and winter, when there's less daylight and the temperature drops. As Auer notes, having fewer hours of daylight does indeed contribute to experiencing SAD. But the disorder isn’t exclusive to cold, dark seasons. In fact, people may experience it under the opposite conditions.

“While SAD is more common in colder climates, it’s the shift in daylight hours — not just the cold — that triggers symptoms,” Attiya Awadallah, founder of Lenora: Art Therapy and Counseling and a licensed psychotherapist who has treated young adults with SAD for over 10 years, tells Yahoo Life. “Even in sunny regions like Arizona, people can experience SAD because the brain reacts to these seasonal changes in light, which can throw off serotonin and melatonin production.”

Adds Auer: “While winter-onset SAD is the most common form, some people experience summer-onset SAD, where symptoms appear during brighter, hotter months."

Again, that’s because SAD isn’t solely about weather, but rather how our body reacts to big environmental changes. “For these individuals, longer daylight hours and intense heat can disrupt their body clocks and cause stress,” Auer explains. “This imbalance can disrupt our energy, sleep, and emotional stability."

Whereas an increase in melatonin (coupled with a drop in serotonin) has been found to cause fatigue and depressive symptoms in people with winter-onset SAD, it's theorized that those with summer-onset SAD may have a reduction in melatonin that makes it harder to sleep. High temperatures, shorter nights and more daylight may also contribute to sleep disruptions, according to the National Institute of Mental Health.

Lastly, more individual factors — like how often a person gets outside — can contribute to SAD. “Some people may have a genetic disposition or an especially sensitive body clock that causes a strong reaction to seasonal changes, even in mild or sunny climates,” Auer adds. “This means that someone living in a sunny state might still feel the effects of SAD, especially if they spend significant time indoors and away from natural light.”

While SAD often presents itself as someone feeling down, that’s not the only way it affects people. “SAD’s impact goes beyond mood,” Awadallah says.

When it comes to summer-onset SAD, Auer says symptoms can include insomnia, loss of appetite or agitation. In the winter, different symptoms may arise, such as hypersomnia (or extreme daytime sleepiness), low energy and carbohydrate cravings that might lead to weight gain, Awadallah adds.

“These physical changes are tied to the brain’s attempt to adjust to the shifts in light exposure, which can cause a drop in serotonin levels,” Awadallah says. While serotonin is considered the “feel-good neurotransmitter,” it also affects sleep, digestion, bone health, sexual desire and more.

Additionally, Awadallah says recent research suggests immune system changes and inflammation may contribute to fatigue and cognitive symptoms found with SAD.

A light box mimics outdoor light, but it’s not regulated by the Food and Drug Administration when it comes to treating SAD, according to the Mayo Clinic.

Auer says light therapy can boost mood and energy for many people, but it isn’t an instant fix or cure-all. “The effectiveness varies from person to person, and like any treatment, it takes time and consistency to see results,” she says. Additionally, she believes light therapy is most helpful when integrated into a holistic approach, in conjunction with other treatments. (Dr. Norman Rosenthal, the psychiatrist credited with discovering SAD, said the same when speaking to Yahoo Life last year.)

Other helpful tips, Auer adds, include cognitive behavioral therapy, regular physical activity, good sleep hygiene and social connection. Awadallah also suggests eating nutritional foods and working on your mental well-being overall.

For someone with SAD, the seasons that bring on their symptoms can feel like an eternity. As the American Psychiatric Association notes, symptoms of SAD typically last up to 40% of the year, further distinguishing the condition from momentary pangs of melancholy.

Coping with SAD takes various adjustments — and people. As with other mental health conditions, it’s not something people should deal with in isolation.

But unfortunately, spending time with others may not be as easy as it sounds for someone with SAD. Depression can make it hard to experience pleasure, have the energy to interact with others or not feel like you're burdensome, which can lead people to them isolating themselves. “Social withdrawal is common with SAD, but isolation only worsens symptoms,” Awadallah says. “Psychologically, withdrawing from social interactions removes a key source of positive reinforcement, which is crucial for maintaining mood stability.”

She recommends behavioral activation, a skill that encourages people to push themselves to do something they would typically enjoy (such as meeting a friend for coffee or going for a walk), knowing that the motivation and mood boost will come later. She says it helps motivate clients to reengage with people and hobbies they love.

It's also crucial that anyone experiencing the symptoms of SAD raise the issue with their doctor. "If you think you may be depressed, see a health care provider as soon as possible," Johns Hopkins Medicine advises. A mental health professional, for instance, can offer guidance on treatment options and coping strategies to help you better weather those harsh seasons ahead.

If you or someone you know is experiencing suicidal thoughts, call 911, or call the 988 Suicide & Crisis Lifeline at 988 or 1-800-273-8255 or text HOME to the Crisis Text Line at 741741.