"Autumn Depression" – Is It Real? What Psychology Says About Shorter Days

As temperatures drop and days grow shorter, many people notice a distinct change in their energy levels and mood — fatigue, apathy, or a pervasive sense of sadness. The popular expression "autumn depression" actually has a precise clinical name: seasonal affective disorder (SAD), a form of depression with a recurring seasonal pattern that, according to specialists, can persist for four to five months a year.

How seasonal affective disorder manifests

This is not simply a passing bout of melancholy. SAD brings real changes in mood, appetite, and energy levels. Those affected feel sadness or a lack of motivation for most of the day, over a period of several consecutive weeks, and lose interest in activities they previously enjoyed.

The most common form — the autumn-winter variant — brings pronounced drowsiness, increased cravings for carbohydrate-rich foods, weight gain, and persistent fatigue. There is also a rarer spring-summer form, characterised by insomnia, reduced appetite, restlessness, and irritability.

What happens in the body as the days grow shorter

The full causes of this disorder are not yet completely understood, but researchers have identified several biological factors involved. Reduced natural light disrupts the circadian rhythm — the internal clock that regulates sleep. At the same time, serotonin levels — the brain chemical that influences mood — fall with decreased sun exposure, whilst melatonin production, the sleep hormone, increases in the autumn-winter form, accounting for the fatigue and greater need for rest. Vitamin D deficiency, which is more common during months with little sunshine, may worsen symptoms through its effect on serotonin.

According to the specialist literature, women, young adults, people with a family history of depression, and those living in areas with winters that offer significantly fewer hours of daylight are more susceptible to this disorder.

How to tell the difference between a simple slump and a genuine disorder

The distinction between a passing autumnal low mood and seasonal affective disorder lies in how intense and prolonged the symptoms are, as well as how significantly they affect everyday life. Specialists recommend consulting a psychologist or psychiatrist when symptoms recur year after year during the same period, intensify as the season progresses, and visibly affect sleep, appetite, or social and professional activities.

Among the treatments used are light therapy (daily exposure of 30–45 minutes to a high-intensity artificial light source), psychotherapy — particularly cognitive behavioural therapy adapted for this type of condition — and, in more severe cases, antidepressant medication, prescribed and monitored by a specialist physician. Some patients choose to begin preventive treatment before symptoms emerge with the onset of a new season.

This article is intended for informational purposes only and does not replace a professional assessment. If you or someone close to you is experiencing persistent sadness, fatigue, or low energy that is affecting daily life, it is advisable to speak with a doctor or psychologist.