Is my winter mood change due to seasonal affective disorder?

Ask the doctors

Q. Every winter I experience mood changes. How do I know if it's seasonal affective disorder?

A. Seasonal affective disorder (SAD) is a type of depression that typically affects individuals during the winter months. Some experts believe it's triggered by a reduction in natural light, which starts in the fall and continues until the spring. Tracking your mood changes can help your doctor determine if you have the condition. People formally diagnosed with SAD experience episodes of major depression that occur in the fall and winter for at least two years. During these episodes, people may feel hopeless or worthless, have sleep problems, or experience changes in appetite or weight. They may also be irritable or anxious and lose interest in favorite activities.