Understanding Seasonal Affective Disorder (SAD)

When the seasons change your mood — it's more than just winter blues.

What Is SAD?

Seasonal Affective Disorder is a type of depression that follows a seasonal pattern, most commonly starting in autumn and continuing through winter.

It's thought to be related to reduced sunlight exposure affecting serotonin and melatonin levels.

Common Symptoms

Persistent low mood during autumn and winter months.

Lack of energy and feeling sleepy during the day.

Craving carbohydrates and gaining weight.

Difficulty concentrating.

Loss of interest in activities you normally enjoy.

Feeling anxious, irritable, or unsociable.

Symptoms typically improve in spring.

What Can Help

Light therapy using a SAD lamp (10,000 lux) for 30 minutes each morning.

Getting outside in natural daylight, especially in the morning.

Regular exercise, even short walks.

Keeping a regular sleep schedule.

CBT specifically adapted for SAD.

Antidepressant medication may help in severe cases.

Vitamin D supplements during winter months.

Educational self-help, not a diagnosis, treatment or crisis service. If you are in immediate danger, call 999. For UK listening support, call Samaritans on 116 123 or text SHOUT to 85258.

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