By Pamela Daniels, Michigan State University Extension For most of the United States, winter came early this year. According to The Weather Channel, since mid-November there have been more than 400 cold and record breaking lows covering 43 states. With this weather change, those suffering from SAD may need to prepare for a longer season of symptoms with these temperatures. What is SAD? Seasonal Affective Disorder (SAD) is a type of depression that's related to changes in seasons - SAD begins and ends at about the same times every year Most people with SAD will begin experiencing symptoms in the fall and continue into the winter months Less often, some people with the opposite pattern have symptoms that begin in spring or summer The specific cause of seasonal affective disorder remains unknown Fall and winter SAD - symptoms specific to winter-onset SAD, sometimes called winter depression, may include: Irritability Tiredness or low energy Problems getting along with other people Hypersensitivity to rejection Heavy, "leaden" feeling in the arms or legs Oversleeping Appetite changes, especially craving foods high in carbohydrates Weight gain What causes of SAD? Although the specific cause of seasonal affective disorder remains unknown, some factors may include: Your biological clock (circadian rhythm). The reduced level of sunlight in fall and winter may cause winter-onset SAD. This decrease in sunlight may disrupt your body's internal clock and lead to feelings of depression. Serotonin levels. A drop in serotonin, a brain chemical (neurotransmitter) that affects mood, might play a role in SAD. Reduced sunlight can cause a drop in serotonin that may trigger depression. Melatonin levels. The change in season can disrupt the balance of the body's level of melatonin, which plays a role in sleep patterns and mood. SAD treatments and prevention Light therapy boxes can offer effective treatment for SAD. Light box therapy may be effective on its own. Or, light therapy may be more effective when it's combined with another SAD treatment, such as an antidepressant medication or psychological counseling (psychotherapy). Be sure to consult with your doctor so that you get a light therapy box that best suits your needs. This is especially important if your sleep patterns and appetite have changed or if you feel hopeless, think about suicide or turn to alcohol for comfort or relaxation. There is help and effective treatment available. Learn how to keep your mood and motivation steady throughout the year. Talk with your healthcare provider and take steps to conquer this long, SAD winter! Visit the Mayo Clinic for more information on SAD and Michigan State University Extension for more information on your health. This article was published by Michigan State University Extension. For more information, visit http:\/\/www.msue.msu.edu. To have a digest of information delivered straight to your email inbox, visit http:\/\/bit.ly\/MSUENews. To contact an expert in your area, visit http:\/\/expert.msue.msu.edu, or call 888-MSUE4MI (888-678-3464).