From Tracee Cornforth,
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Many women experience occasional periods of the "winter blues." However, when the "winter blues" are more than occasional and seem to happen over and over again during the Fall and Winter and not in the Spring or Summer, you may have seasonal affective disorder or SAD. This disorder affects an estimated 35 million Americans to varying degrees. Of these, at least 10 million experience a serious disruption in their lives due to seasonal affective disorder. Did you know that those most likely to be affected by SAD include children, adolescents, and women? In fact, 75 to 80 percent of those who suffer from seasonal affective disorder are women; the majority of women affected by SAD are over age 30.

Symptoms of SAD

The most common symptoms of seasonal affective disorder include:

• Lack of energy including increased fatigue, an increased need for sleep, and lethargy.

• Increased appetite, possible weight gain, and increased cravings for sugar and carbs.

• Withdrawal from friends and family, relationship problems, loss of libido, and anxiety.

• Problems with focusing or concentrating on various types of tasks or work.

• An increase in the symptoms of premenstrual syndrome or PMS, or premenstrual dysphoric disorder which is also called PMDD.

• Seasonal depression during Fall and Winter.

If you experience severe depression with SAD, it's imperative that you receive an evaluation of your symptoms so that a proper diagnosis is made. While the symptoms of major depression are consistent from morning to night, the severity of the symptoms of SAD, such as depression and fatigue, increase throughout the day.

What Causes Seasonal Affective Disorder?

Where you live is an important factor to consider; people who live in far northern regions of the Northern hemisphere or in extreme southern regions of the Southern hemisphere are more likely to experience SAD. In fact, the further north or south you live from the equator the more at risk you become. In the U.S., it's estimated, that as many as 25 percent of the people who live in the northern region may experience seasonal affective disorder. The shorter daylight hours and the reduced amount of sunlight to the retina causes SAD. This is because sunshine increases the body's production of serotonin, and increased levels of melatonin. Together, these seasonal fluctuations cause seasonal affective disorder in some people. Normal sleep -- wake cycles cause variations in our levels of both serotonin and melatonin. These variations allow us to sleep at night and stay awake during the day. When your brain chemistry is off balance your serotonin level may not have enough daylight hours to increase to the level it does during Spring and Summer months.

Treating Seasonal Affective Disorders

Light therapy effectively improves the symptoms of SAD. Because a lack of sun causes SAD, it makes sense that therapy with lights is the preferred treatment. Light therapy increases light to the brain through your retina. Treatment of seasonal affective disorder with light therapy is effective for from 60 to 80 percent of patients, with most patients noticing significant improvement within four to five days.

How Does Light Therapy Work?

Special lamps may be purchased for the purpose of light therapy. These lamps should have a power rating of at least 10,000 lux. This is equivalent to five to twenty times the normal lighting in your home or office. SAD lamps should be used everyday during the peak seasons in which this disorder occurs. For effective treatment you'll need to sit in front of your light therapy lamp from 30 minutes to two hours daily. You should not look directly at the light source. While your in front of your light therapy lamp you can read, watch TV, work at your computer, or anything else you can do while sitting. Although most SAD patients prefer to use their lamps when they wake up in the morning, you can also do this in the evening. The time you pick to do your seasonal affective disorder treatment depends on you and the time of day that you feel it's most effective. You may also find it helpful to set an automatic timer to start the lamp two hours before you wake up in order to create a natural sunrise affect.