Seasonal affective disorder (SAD), also called seasonal depression, is a type of depression. It’s triggered by the change of seasons and most commonly begins in late Autumn. Symptoms include feelings of sadness, lack of energy, loss of interest in usual activities, oversleeping and weight gain. Treatments can include but are not limited to - light therapy, talking therapy and in the most extreme of cases, antidepressants. 12pm, Wednesday, 3rd December 2025