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Could I Have Seasonal Affective Disorder?

Symptoms of SAD

Could I Have Seasonal Affective Disorder?


What are the Symptoms of SAD?


Common symptoms of SAD include fatigue, even when you have had plenty of sleep and weight gain due to overeating and carbohydrate cravings. SAD symptoms can range from mild to severe and can include many symptoms similar to major depression, such as:


  • a persistent low mood
  • a loss of pleasure or interest in normal everyday activities
  • irritability
  • feelings of despair, guilt, and worthlessness
  • feeling lethargic (lacking in energy) and sleepy during the day
  • sleeping for longer than normal and finding it hard to get up in the morning
  • craving carbohydrates and gaining weight
  • difficulty concentrating
  • decreased sex drive


For some, some of these symptoms can be severe and have a significant impact on your daily activities.

For winter-pattern SAD, additional specific symptoms may include:


  • Oversleeping (hypersomnia)
  • Overeating, particularly with a craving for carbohydrates
  • Weight gain
  • Social withdrawal (feeling like “hibernating”)


Specific symptoms for summer-pattern SAD may include:


  • Trouble sleeping (insomnia)
  • Poor appetite, leading to weight loss
  • Restlessness and agitation
  • Anxiety
  • Episodes of violent behavior


SAD is more than just “winter blues.” However, it can be treated. About 5 percent of adults in the U.S. experience SAD and it typically lasts about 40 percent of the year. It is more common among women than men.


What causes SAD?


Scientists do not fully understand what causes SAD. Research indicates that people with SAD may have reduced activity of the brain chemical (neurotransmitter) serotonin.


Serotonin is a chemical messenger that's believed to act as a mood stabilizer. It appears to help produce healthy sleeping patterns, improve digestion as well as boost your mood.


Sunlight controls the levels of molecules that help maintain normal serotonin levels, but in people with SAD, this regulation does not function properly, resulting in decreased serotonin levels, especially in the winter.

Hopkins medicine suggests that people that overproduce melatonin can lead seasonal affective disorder. Melatonin is a hormone that is central to maintaining the normal sleep-wake cycle. Overproduction of melatonin can increase sleepiness.


Both serotonin and melatonin, which maintain the body’s daily rhythm that, can impact the seasonal night-day cycle.  People with SAD struggle to adjust to the seasonal changes in day length, leading to sleep, mood, and behavior changes.


A deficiency in vitamin D may accelerate these problems because vitamin D is said to promote serotonin activity. Vitamin D consumed through the food you eat is also produced when your skin is exposed to sunlight. With less daylight in the winter, people with SAD may have lower vitamin D levels, which could further slow down serotonin activity.


sad help

How can SAD be treated?


Treatments are available that can help many people with SAD. They fall into four main categories that may be used alone or in combination:


  • Light therapy
  • Psychotherapy
  • Antidepressant medications
  • Vitamin D


For Impact members, Virtual mental health care is eligible for sharing through a teletherapy provider according to the details in the member Guidelines.


If mental health is not covered by your health insurance Open Enrollment is a great time to switch and get the coverage you need.


If you’d like to learn more about Impact and what membership includes, we can chat online or via phone or email.




If you or someone you know needs help, this hotline is available at any time, day or night.


SAMHSA’s National Helpline is a free, confidential, 24/7, 365-day-a-year treatment referral and information service (in English and Spanish) for individuals and families facing mental and/or substance use disorders.


The information provided on the site is for educational purposes only and does not substitute for professional medical advice. Readers should consult a medical professional when seeking medical advice, diagnoses, or treatment.