A young woman with a sad expression on her face

How to Identify & Manage Seasonal Affective Disorder (SAD)

With the shrinking days of December comes for many of us the “winter blues”. Many people report lower energy levels and more sadness come winter as they are staying inside more and seeing less of the sun. Roughly 10-20% of the U.S. population reports experiencing some form of winter blues, but for 5% of the population it becomes more than blues. Seasonal Affective Disorder (SAD) is a form of depression that usually presents itself during the fall and winter. SAD, just like other depressive disorders, can impact not only your mood but your thoughts and relationships. SAD can also be treated through a variety of preventive measures and coping strategies, as we will discuss later in this article.

What is SAD?

SAD is a mood disorder similar to other depressive disorders in that it's marked by a sad mood and low energy that can impact several areas of one’s life. What makes SAD different, however, is that it is typically linked to seasonal patterns. The most common form of SAD presents at the beginning of fall and reaches its peak in the winter months; however, there are rare forms of SAD that present as depressed moods happening during summer. It’s also important to note that SAD doesn’t impact all people equally. Some folks who may be more likely to experience SAD include:

  • Women - around 75% of all folks diagnosed with SAD
  • Young adults ages 20-30
  • People diagnosed with other mood disorders (i.e. depression, bipolar disorder)
  • People diagnosed with other mental health disorders (i.e. anxiety, schizophrenia, ADHD)
  • People who live further from the equator

There is not one singular accepted explanation yet for what causes SAD, but there are several likely culprits. Many theories are linked to the decreased exposure to sunlight, which can change our body’s functions. A lack of sunlight can decrease the production of Vitamin D in our bodies, a vitamin that helps boost mood regulating chemicals like serotonin. Less light can also signal our bodies to produce more melatonin, a chemical associated with sleep-wake cycles that causes us to feel tired.

How do I know if I have SAD?

One of the first ways to check if you have SAD is to review some of the common symptoms, which include: depressed mood, anxiety, low energy, problems with sleep, hopelessness, low motivation, higher appetites, and low libido. If any of these symptoms sound like what you’re experiencing, it’s possible that you may have SAD; however, the only way to know for sure is to receive a diagnosis from a healthcare professional. Mental health counselors, psychiatrists, psychiatric nurse practitioners, and general practitioners are all great resources to consult. They may implement different kinds of assessments, from spoken interviews to blood tests, to see if you may have SAD.

Regardless of who you start with, it’s important to consult with a professional if you are experiencing any symptoms that may be impacting your mental health. While there are many ways you can work to treat and prevent SAD at home, it’s important to verify with a clinician that what you are experiencing is SAD and not another condition, such as Major Depressive Disorder, which may not respond to treatments the same way.

How do you treat SAD?

The most common form of treatment for SAD is light therapy, also known as phototherapy. Light therapy utilizes special kinds of lamps that work to mimic exposure to actual sunlight. These lamps tend to be around 10-20 times brighter than your regular indoor light to do this. For a light therapy lamp to be effective, the bulb should have an intensity of 10,000 lux. Due to the brightness of the lamp, you should not stare directly into the lamp. Ideal light therapy includes being around 2-3 feet from the lamp while focused on another task - maybe reading a book, tending to emails, or even meditating with your eyes closed. In most cases of SAD, light therapy can treat symptoms - around 85% report improvement with phototherapy.

Outside of light therapy, some research has also shown the effectiveness of Cognitive Behavioral Therapy (CBT) for treating SAD. CBT is a form of talk therapy that focuses on challenging unhealthy ways of thinking and increasing understanding of one’s own thought patterns. A major benefit for the use of CBT is that research has been shown that this form of treatment is effective in treating many psychological concerns; this could make CBT a great form of treatment for those already diagnosed with other conditions that also experience SAD.

Treatment may also include medications or supplements. Antidepressants can be helpful for some with SAD by increasing serotonin levels in brain cells. Clinicians may also encourage people to take Vitamin D supplements if a patient has low levels, since this can also promote serotonin activity.

How can I prevent SAD?

As with all psychological concerns, one of the best places to start prevention is with overall health. Physical exercise and healthy, balanced diets can help to prevent SAD and other mood disorders. Avoiding excessive use of mood altering substances, such as alcohol and nicotine, can also help in prevention work. Spending more time outside can also be a helpful strategy for some folks.

Starting to focus on prevention at the beginning of fall is important. If you utilize phototherapy, it’s best to start regular light therapy treatment in early fall before symptoms begin. Engage with other mental wellness strategies, such as therapy, mindfulness meditation practice, or journaling before symptoms start when possible. Coping ahead of time by creating plans that can help boost your mood in the darker months can also be a great form of prevention. Regardless of what strategies you use, it’s also important to regularly meet with your general practitioner that can help you stay connected with your overall health.


This time of year, many of us are at risk of experiencing SAD or lesser forms of the “winter blues”. Whether or not you meet a full diagnosis of SAD, it’s important to check-in with ourselves this time of year, both mentally and physically. If you’re noticing more sadness this time of year, it’s important to talk with a therapist or another health professional to start identifying ways that you can be your best self all year round.

Resources for SAD: