Why Mood Worsens in Autumn and Winter and When to Seek Medical Advice

Experts recommend not ignoring prolonged mood changes and seeking medical help when necessary.

According to the Cleveland Clinic, 10% to 20% of Americans experience a mild decline in mood during the darker months of the year. Seasonal affective disorder differs in that its symptoms can significantly affect daily life and persist for four to five months.

The most common form is winter-pattern seasonal affective disorder, which typically begins in late autumn or early winter and eases in spring. A summer-pattern form also exists, with symptoms appearing in late spring or early summer.

The exact causes of the disorder have not yet been established. Researchers believe that genetics, brain function and disruptions to biological rhythms may all play a role. In particular, shorter daylight hours may affect serotonin activity, which helps regulate mood, and melatonin, which helps the body maintain its sleep-wake cycle.

Possible symptoms include persistent low mood, loss of interest in usual activities, fatigue, difficulty concentrating, irritability, and changes in sleep, appetite and weight. If these symptoms persist for two weeks or longer, experts recommend consulting a doctor.

Seasonal affective disorder is treatable. One of the main approaches is light therapy using a special lamp with an intensity of 10,000 lux. Craig Sawchuk, a psychologist at the Mayo Clinic, recommends sessions lasting approximately 20 minutes within the first hour after waking up. Other treatment options include cognitive behavioral therapy and antidepressants prescribed by a doctor on an individual basis.

Everyday habits may also help, including spending time outdoors in daylight, engaging in regular physical activity, staying connected with loved ones and maintaining a consistent daily routine. If symptoms recur every year, experts recommend discussing preventive measures with a doctor before the next seasonal episode begins.