by Amy Morin, LCSW

As a therapist living in the Northeast, I see an interesting phenomenon every time the calendar changes from summer to fall: Sometime around the end of October, requests for therapy start to skyrocket.

The weather, the seasons, and the length of day can have a big impact on your mood. While some people experience a slight winter slump, others become downright depressed as the days get shorter. Seasonal Affective Disorder (with the fitting acronym SAD) often gets triggered shortly after daylight saving time begins. Going to work in the dark and coming home in the dark can take a serious toll on your mental health. Many people experience symptom progression as the months pass, until finally gaining relief again in the spring.

Researchers aren’t exactly sure why some people experience SAD. Some factors that may play a role include decreased serotonin and melatonin in the brain, stemming from the lack of sunlight. The decreased daylight may disrupt your biological clock, which can lead to sleep issues and mood problems.

Here are seven signs you may have SAD:

  1. Ironically, sometimes people with SAD aren’t especially sad; instead, they experience impatience and frustration.
  2. Decreased energy. People with SAD often want to sit on the couch or stay in bed. They struggle to find the energy to carry out normal daily activities.
  3. Weight gain. Although weight gain may result from the decreased activity that often accompanies the winter months, people with SAD also tend to overeat. They typically reach for starchy and sweet foods which can contribute to weight gain.
  4. Social problems. When SAD takes hold, many people don’t want to socialize. They’re often hypersensitive to criticism and their irritability can lead to relationship problems.
  5. Sleep problems. Too much darkness can wreak havoc on a person’s sleep/wake cycle. Many people with SAD have difficulty falling asleep; often, they don’t feel rested in the mornings.
  6. Increased anxiety. People with SAD sometimes experience increased anxiety and a decreased ability to tolerate stress.
  7. Mood changes. Individuals with SAD experience a stark change in mood and behavior during the winter. An outgoing person (in other seasons) may become withdrawn, or an energetic person may become lethargic. 

Treatment for SAD

You may be able to treat mild symptoms of SAD yourself:

  • Bright sunlight—especially in the morning—and outdoor activity can help boost your mood. Going for a walk before work or during your lunch break may help alleviate some of the problem.
  • Find some enjoyable wintertime activities. Participating in outdoor activities like snowshoeing or cross-country skiing can reduce negative feelings about the winter months.
  • Bright light therapy is another effective option. A specially-designed light box can simulate sunshine and regulate your body’s internal clock. Similar to a bright spring day, daily exposure to the bright light may be able to prevent the body from producing too much melatonin.
  • Cognitive behavior therapy and medication may also be effective in reducing symptoms. These therapies may be used in combination, or combined with bright light therapy.

If you think you may be experiencing SAD, talk to your doctor. Your physician can rule out physical health conditions and suggest strategies to make the winter months less gloomy.
Bio:
Amy Morin is a psychotherapist, psychology instructor, and speaker. Her book 13 Things Mentally Strong People Don’t Do is on sale now. She’s frequently quoted in national media outlets. She also writes for Forbes and About.com. For more visit AmyMorinLCSW.com

*This article originally appeared in forbes.com.