Feeling that you have a case of the ‘winter blues'? Don't just brush it off - Seasonal affective disorder (SAD) is a type of depression that occurs at the same time every year. Most people with SAD start feeling their symptoms in the fall and this continues in the winter months.

Seasonal affective disorder is a seasonal or cyclic condition. Symptoms may start out mild and become more severe over time.

Winter-onset seasonal affective disorder symptoms include: 
• Depression
• Hopelessness
• Anxiety
• Loss of energy
• Social withdrawal
• Oversleeping
• Loss of interest in activities you once enjoyed
• Appetite changes, especially a craving for foods high in carbohydrates
• Weight gain
• Difficulty concentrating and processing information

If you are feeling down for days and cannot seem to get motivated to do activities you normally enjoy - you should schedule an appointment with your doctor. Changes in sleep patterns and appetite, thoughts of suicide are also concerning symptoms.

Mental health conditions, genetics, age, your body's chemical makeup all contribute to the development of seasonal affective disorder. Specific factors include a disruption of your circadian rhythm (biological clock) due to reduced level of sunlight in the fall and winter. Changes in season can disrupt the balance of the natural hormone melatonin which plays a role in sleep patterns and mood. Reduced sunlight can also cause a drop in levels of serotonin, which can affect mood.

Women are more likely to be diagnosed with SAD than men. People who live far north or south of the equator are more likely to suffer from SAD and people with a family history of SAD are more likely to have the condition.

When left untreated, seasonal affective disorder can worsen and lead to problems. Serious symptoms include - suicidal thoughts, social withdrawal and substance abuse.

Treatment for seasonal affective disorder includes light therapy (phototherapy), psychotherapy, exercise, along with vitamin D and essential fatty acids. Addressing the problem can help you keep your mood and motivation steady throughout the year.