People are most frequently affected by SAD in the fall and winter, but it can also occur in the spring and early summer.

Ashley Clay, MSPAS, PA-C
Medcor Provider

If you or a loved one suffer from “winter blues,” with prolonged periods of low energy and tiredness, weight gain, decreased interest in activities, difficulty concentrating, and feelings of hopelessness, worthlessness, or guilt during the colder, darker days of fall and winter—it is time to talk to a healthcare provider about depression and the possibility of Seasonal Affective Disorder (SAD).

SAD is a type of depression that correlates with changes in the season; more commonly a shift in mood that begins in the fall and continues during winter months (less commonly, some people experience a change in mood and behavior in spring or early summer).

What Causes SAD?

Experts think SAD may be triggered by decreases in sunlight which disrupts your internal clock. Reduced sunlight can cause an imbalance of important chemicals in your body, such as melatonin—which signals your body that it is time to sleep when your body releases it—and serotonin, which is a brain chemical that affects mood.1

What Are Possible Complications?

As a kind of depression, people who suffer from SAD are at risk for depression-related complications such as anxiety, substance abuse, social withdrawal, eating disorders, and suicidal thoughts or behavior.2 A common misconception is that suicide rates increase during the holiday season—this is not accurate, but suicide does claim more than 36,000 lives each year in America.3 If you or someone you know is in distress, call the free, confidential National Suicide Prevention Lifeline at 1-800-273-8255, which is available 24/7.

What are some facts about SAD?4

  • SAD is four times more common in women than men.
  • Your distance from the equator increases the likelihood of this condition. For example, one percent of Floridians suffer from SAD, whereas nine percent of Alaskan residents suffer from SAD.
  • Younger people and those with a family history of depression are at greater risk for SAD.

Can SAD be Treated?

SAD is treatable. It is important to discuss strategies for easing SAD symptoms with a healthcare provider. Treatment options for SAD may include taking antidepressant medication, taking vitamin D supplements, light therapy, and cognitive behavioral therapy.5 

This article is not intended to diagnose or treat any condition or to give medical advice. Always consult your healthcare provider for healthcare instructions. External links are provided as references and do not indicate an endorsement by Medcor. External links are subject to other sites’ terms of use and privacy policies.

1 Mayo Clinic, “Seasonal affective disorder (SAD),”

2 Ibid.

3 Centers for Disease Control and Prevention, “Holiday Suicides: Fact or Myth?,”

4 National Institute for Mental Health, “Seasonal Affective Disorder,”

5 Ibid.