As daylight hours shrink and temperatures drop, health experts say many Americans may experience seasonal depression, a form of mood disorder linked to reduced exposure to natural light during the winter months.
Often referred to as Seasonal Affective Disorder, or SAD, the condition is most common in northern regions where winter days are shorter and sunlight is weaker. Symptoms can include a persistent low mood, fatigue, difficulty concentrating, changes in sleep patterns, and a loss of interest in activities that are normally enjoyable.
Experts note that while working in naturally lit rooms can help support overall well-being, indoor daylight typically falls far short of the light levels needed to significantly counter seasonal depression. Even bright indoor environments often provide only a fraction of the light intensity people receive outdoors, particularly during winter.
By comparison, outdoor light—whether on a sunny or overcast day—is substantially stronger. Health professionals say spending time outside in the morning, even briefly, can be beneficial. Importantly, the mood-regulating effects of light come from exposure through the eyes, not from sunlight on the skin, meaning heavy winter clothing does not diminish the benefit.
For individuals who struggle to get outside regularly, light therapy has emerged as a widely recommended option. Light therapy boxes are designed to emit bright, full-spectrum light that mimics outdoor conditions. When used consistently—typically for 20 to 30 minutes in the morning—these devices have been shown to improve mood, energy levels, and sleep patterns for many people.
Doctors also emphasize the importance of maintaining regular sleep schedules, staying physically active, and maximizing exposure to natural light whenever possible. Simple changes, such as taking a morning walk, working near windows, or opening blinds early in the day, can provide added support.
While seasonal mood changes are common, experts advise individuals experiencing persistent or severe symptoms to seek medical guidance. Early recognition and proactive strategies, they say, can make a meaningful difference during the darkest months of the year.
With winter now well underway, health professionals encourage residents to be mindful of their light exposure and to take steps that support both mental and physical well-being as the season progresses.