Seasonal Mood Issues: What you need to know


By Michael DeVries O2X Resilience Specialist (Lieutenant Colonel in the U.S. Army, Command Psychologist Ph.D.)

This time of year, my wife and I often find ourselves looking at each other early in the evening and one of us saying something like, “I can’t believe it is only six thirty! It feels like nine thirty!” This is especially common after the fall time-change. It feels like you lose time in the evenings when it gets dark at 4:30 or 5:00 in the afternoon.

For some, experiencing fewer hours of light each day is just a minor annoyance, but others might start to feel something more like clinical depression as the seasons change. Have you ever found yourself feeling more down, sleeping too much, or having less energy in the fall or winter? Did you ever feel like this was significant enough that it interrupted your life? If that sounds familiar, keep reading. 

Seasonal Affective Disorder

Depression that comes on with the change of seasons in the fall and winter, coinciding with having more hours of daily darkness, is called Seasonal Affective Disorder (SAD). According to the National Institute of Mental Health, SAD is more common in the northern regions, which experience even fewer hours of light each day. It is also more common in those who suffer from other forms of depression or mental health conditions. 

Symptoms of SAD to look for… 

Symptoms of SAD include those of depression in general: 

  • Sleep disruption (usually SAD sufferers sleep more than normal)
  • Loss of interest in pleasurable activities
  • Feelings of helplessness or hopelessness 
  • Low energy
  • Difficulty concentrating
  • Appetite changes (typically eating more, especially carbs)
  • Thoughts of death or suicide
  • People with SAD may feel like hibernating, gain weight, and oversleep

What causes SAD? 

Scientists don’t have a clear understanding of the connection between decreased hours of sunlight and symptoms of depression. The leading theory is that sunlight impacts the neurotransmitter systems that  regulate serotonin and melatonin. Serotonin is key to mood regulation, while melatonin helps our body regulate the sleep-wake cycle. When our serotonin levels are out of whack, we can experience issues with our mood. Too much melatonin in our system can cause increased sleepiness, which can throw off our mood as well. Additionally, exposure to sunlight produces vitamin D. Deficits in vitamin D can reduce energy levels. 

So what do I do now?

You may be asking, “So what should I do if I find myself feeling worse with the return of the winter months?” First off, if you are experiencing symptoms of depression that are significantly impacting your work or personal life, it is a good idea to seek professional help to get back on track. There is no need to struggle alone when you can have a professional guide to help you feel better. 

It is also important to make sure you are treating the right issue. If the doctor thinks you may be suffering from SAD, then light therapy, vitamin D, psychotherapy, and medications can help.

If your symptoms are more minor or you want to act proactively (always the best answer), the O2X Eat, Sweat, Thrive roadmap is always a good place to start. Many times, decreased daylight leads to subtle changes in our behaviors, which negatively affect our ability to Thrive. For example, you may find that your evening routine of exercise, playing with the kids outside, working on your hobby, or doing some yard work gets interrupted when it gets dark earlier. It’s important to find ways to stay active, engage in fun activities, and enjoy family time, even when it’s dark out. 

Additionally, you need to continue healthy eating habits. With the loss of vitamin D from sunlight, you need to ensure that your diet or multivitamins are providing you enough to compensate. Your physician or a nutritionist can help you check your levels of vitamin D and suggest ways to keep you in the right range. Finding time for a short walk outside in the sun during the day is a great way to get some vitamin D, exercise, and stress relief all in one activity. Even short 10-15 breaks can help. You can also buy light therapy lights pretty reasonably. Try adding one to your office and brighten your day that way. 

Also, make sure that your physical fitness regimen has not fallen off. Maintaining your fitness goals throughout the year is important to staying healthy and regulating mood. If you slack in your fitness, it can impact your mood, your sleep, and your attitude.  

Still 24 Hours Each Day

We say things like, “The days are getting shorter,” but what that really means is we have fewer hours of light each day. This sounds obvious, but we may start acting like we have fewer hours to accomplish our goals or enjoy leisure activities. These subtle changes in attitude and behavior can set us back in our performance, or can keep us from enjoying our free time. Being proactive and intentional about maintaining good habits from season to season can keep us thriving all year round. 


About the Specialist: Michael DeVries is an O2X Resilience Specialist. He is an Army Psychologist with over 18 years of experience working with high performance teams in the military and civilian sectors. Michael has his Master’s and Doctorate degrees in Counseling Psychology from Western Michigan University. Prior to the military, he worked as a facilitator for corporate team building events. For the past 11 years, he has worked with Special Operations units across the Department of Defense. Michael is board certified in Organizational and Business Consulting and is a certified business coach. His areas of expertise include executive coaching, leader coaching and development, assessment and selection, training support, performance psychology, and program evaluation through data analysis.