By Denise Tausig, for SparkPeople
For many people, cold weather and a lack of sunshine can bring on a mild depression known as the ''winter blues.'' People that experience the ''winter blues'' will generally lack motivation and energy. Others may even develop a clinical depression in the form of SAD (Seasonal Affective Disorder).
According to the Mayo Clinic, SAD is ''a type of depression that occurs at the same time every year. If you're like most people with seasonal affective disorder, your symptoms start in the fall and may continue into the winter months, sapping your energy and making you feel moody.'' Those that experience SAD may produce too much melatonin, which is a hormone that helps to regulate sleep and body temperature. Producing too much melatonin disrupts the body's internal clock and may then cause depression, as seen with SAD sufferers.
Some of the signs of SAD may include the following:
- Loss of energy
- Social withdrawal
- Difficulty concentrating
- Depressed









