FORT LEONARD WOOD, Mo. (Army News Service, Jan. 17, 2007) - As quickly as the holidays came, they are now over. For most people the stresses of the season are subsiding, but for others the wintertime blues just won't go away.

Seasonal Affective Disorder, SAD, is where individuals suffer from symptoms of depression during the fall and winter, and according to the American Psychiatric Association, it is all because of a lack of sunlight.

During the winter months there is less daylight, and people tend to stay inside more due to the cold. Also, during the seasons change, people may experience a shift in their biological internal clock, disrupting sleep patterns, say APA experts.

The symptoms of SAD are close to that of depression and include oversleeping, daytime fatigue, carbohydrate cravings, weight gain, hopelessness, lack of interest in normal activities, social withdrawal and decreased sexual interest, according to the National Alliance on Mental Illness.

Most SAD sufferers are young adults and women, according to APA statistics. The average age is 18-30, but SAD can start at any age.

Recognition of this disorder can be half the battle. SAD may be mistaken for hypothyroidism, hypoglycemia, infectious mononucleosis and other viral infections. The APA urges those with symptoms to seek a proper evaluation by a health care provider.

Most SAD symptoms can be controlled with antidepressants and therapy, but the main line of defense can be very bright. NAMI experts say bright white fluorescent light has shown to reverse the effects and symptoms of SAD. Lights are placed in a box at eye level with a diffusing lens to block out ultraviolet radiation. Studies have shown that approximately 50 to 80 percent of light therapy users have seen a reduction in symptoms.

Light boxes can be purchased on the Internet, but experts recommend first taking walks on sunny days, re-arranging an office to face a window or spending more time outdoors if possible.

Information on SAD symptoms is available at the Center for Environmental Therapeutics's Web site, . The site offers a free, confidential questionnaire that uses a depression-scale inventory. The answers can be used to analyze symptom patterns and the severity of them. Result summaries are individualized and can be taken to health care professionals for further evaluation.