For many of us - especially those who live at higher latitudes in the Northern Hemisphere - the seasonal onset of colder weather and waning sunlight is accompanied by negative trends in both our mood and energy.
The symptoms of seasonal affective disorder (SAD), which can range from irritability, negative thinking, and feelings of fatigue to full-blown depression, are experienced by nearly 5 percent of the U.S. population each year.
But as we enter the winter months in the midst of a global pandemic, experts are nearly certain those number will rise.
COVID-19 has already contributed to a surge in mental health issues - even among people who don't normally experience psychiatric problems. And it's likely to intensify SAD and other mood disorders.