It doesn’t take a psychiatrist to confirm that weather affects your mood. If it’s rainy, things can get a little gloomy, and if it’s sunny, there’s often an extra pep in your step. But if the winter doldrums bring depression year after year, seasonal affective disorder (SAD) could be to blame.

What to Know

SAD is a form of depression that typically occurs during the winter months with symptoms weaning off during the spring and summer— though some people experience their most intense symptoms during the summer. Symptoms include decreased concentration, increased appetite, weight gain (whereas some other forms of depression can lead to weight loss), social withdrawal, moodiness, and fatigue.

Though some people write it off as simple moodiness, SAD is a real form of depression that’s dependent on a person’s hormonal state, seasonal characteristics like temperature, and exposure to natural light (which can influence the body’s production of melatonin).

Research has found it’s more prevalent in regions that have more intense and longer winters. That explains why about two percent of the U.S. population suffers from SAD, while the rates in Canada are double that. One in 10 Americans also experiences subsyndromal SAD, a more mild form of the disorder often referred to as “winter blues.” And though the disorder affects both sexes, it’s more common among women.

How to Fight SAD

It’s sometimes difficult to determine whether a bout of sadness is indeed an indication of SAD, so a doctor’s visit is the first step on the road to treatment. Symptoms can be similar to other forms of depression, so it can be misdiagnosed. Fortunately, there are a range of treatments to help combat SAD.

1. Get some fresh air.

Spending time outdoors helps ease symptoms of SAD. Try to get outside within two hours of waking up. Whether it’s cloudy or sunny, spending some time in the daylight can be a big help.

2. Try light therapy.

Doctors may prescribe light therapy to reduce SAD symptoms.Seasonal+affective+disorder.+A+description+of+the+syndrome+and+preliminary+findings+with+light+therapy.+Rosenthal+NE,+Sack+DA,+Gillin+JC.+Archives+of+general+psychiatry,+1984,+Feb.;41(1):0003-990X. But staring at the Rockefeller Center Christmas tree won’t cut it— treatment for this condition comes in box form. Light therapy boxes range in brightness and type of light, so consult a physician before buying one.

3. Talk it out.

One study found cognitive behavioral therapy was just as effective as light therapy in treating SAD. (A combination of talk therapy and light therapy together was also effective.)

4. Consider antidepressants.

Antidepressants can control mood and energy. A psychiatrist can help decide if medication is an appropriate treatment option.

5. Exercise.

Regular exercise can reduce symptoms of moderate, nonseasonal depression. And studies suggest a combination of exercise and light therapy can also help treat SAD.Randomized+trial+of+physical+exercise+alone+or+combined+with+bright+light+on+mood+and+health-related+quality+of+life.+Partonen+T,+Leppämäki+S,+Hurme+J.+Psychological+medicine,+1999,+Mar.;28(6):0033-2917. So put Netflix on pause and consider going for a jog instead.

6. Eat carbs.

Complex carbohydrates can help maintain levels of serotonin, a neurotransmitter that regulates mood. (Eat those carbs in moderation, of course— it’s hard to feel chipper after a box of Chips Ahoy!)

The Takeaway

Though cold weather is likely to have a lot of us wishing for spring, it’s important not to cast off SAD as an inevitable winter side effect. Taking action when symptoms hit could make the difference between a lonesome stretch and a happy winter season.

Originally published January 2012. Updated December 2015.