Why so Sad?: Shedding Light on SAD

Fence covered in snow with trees and sunset in the distance.
SAD, or seasonal affective disorder, was first characterized in 1984 by Norman Rosenthal, M.D., professor of psychiatry at Georgetown University Medical School, after he reviewed the attitudes of people in different latitudes to see the effects of light on mood. When he compared a group of Floridians to a cohort of East Coasters in seasonal mood states, he noticed, not surprisingly, that the members of the warmer, sunnier group were less depressed.
While many people say that they prefer the long, bright days of summer to the short, sunless days of winter, when do the ‘winter blues’ become SAD, a mental health disorder for which there are effective treatments?

SAD is a form of depression that is considered cyclical, presenting in the fall, and remitting by spring. It is found in 5-10 percent of the U.S. population and affects women at four times the rate of men, with onset mostly in adulthood. Characteristics include changes in mood, outlook and physiology over at least a two-week period.

Central to the diagnosis of SAD is exposure to sunlight. Our sleep-wake cycle, or circadian cycle, is roughly a 24-hour internal clock run by contact with light. Important hormones such as serotonin (mood regulation) and melatonin (the sleep hormone) fluctuate through the day informing our bodies when to rise, eat, and sleep.

Dr. Rosenthal also noted that stress and biological predisposition, in addition to environmental light, can cause SAD. Given how in Iowa we spend roughly 40 percent of the year in seasons with fewer daylight hours, diagnosing and treating SAD is important to our well-being.

So what can be done to improve the symptoms of SAD? Here are five ways to manage symptoms: light exposure, talk therapy/CBT, stress management, diet/exercise, and medication.

Light Exposure

While we may know that getting more light helps SAD, exactly how it works is the question. Whereas it would be lovely to have weekly trips to warmer climates, doing so isn’t realistic. Instead, daily light therapy is recommended.

The Mayo Clinic emphasizes the importance of consistency in regimen starting in fall when natural light starts to diminish and ceasing treatment as the days lengthen. Visit the Mayo Clinic website for tips on how to choose the right light therapy box for you.

Talk Therapy or Cognitive Behavioral Therapy

Therapy can be helpful in developing emotional and behavioral strategies to cope with the symptoms of SAD. Research conducted by Kelly Rohan, Ph.D., professor of psychological sciences at the University of Vermont, demonstrated that teaching people “to challenge negative thoughts about dark winter months and to resist behaviors like social isolation” is equally effective to the use of daily light therapy.

Stress Management

Setting realistic goals about projects through the winter is recommended. In addition, managing stress by getting a handle on our thoughts can be helpful. Mindfulness Based Stress Reduction, an evidence-based program for managing stress, is offered at no cost for UI faculty and staff with a health coach referral at the University of Iowa Hospitals and Clinics.

Diet and Exercise

People with SAD often crave sweets and starches. In line with general recommendations for good dietary health, eating protein, vegetables, and complex carbohydrates will prevent energetic peaks and valleys which accompany the consumption of sweets and starches. SAD experts also recommend daily exercise in any form, especially walks outdoors early in the day.


People with significant impairment in their work or personal life due to symptoms of SAD may need to consider medication. This option, as with the treatment of any mental health condition, is determined through conversation and consultation with your doctor.

What can you do if you feel blue or more depressed this winter? First and foremost, consult your physician for an assessment and to learn what might be helpful for you. For additional information or resources, your Employee Assistance Program offers free counseling for UI employees. We're here for you and can be reached at 319-335-2085 or eaphelp@uiowa.edu.

This article originally appeared in the winter 2019 liveWELL newsletter.