Seasonal Adjustment Disorder or SAD /S.A.D is a type of depression, lowered mood that seems to descend in the winter months. One theory is that it is the result of a lack of Vitamin D which the body produces in response to exposure to sunlight. Reduced sunlight in the winter can therefore affect our Vitamin D production. Though Vitamin D can be obtained from food, a deficiency in both food and exposure to the sun can be detrimental to our overall mental health resulting possibly in SAD.
Vitamin D is believed to affect Seratonin production in the brain. Seratonin levels affect our mood and a lowered Seratonin level can result in us feeling down, depressed,anxious etc.
Thus a lack of sunlight = lack of Vitamin D = lack of Seratonin = lack of good mood.
This is an over simplification, for a more scientific explanation follow the links below.
So what can we do about S.A.D?
While neither a Doctor or an expert on SAD I would recommend the following based on my own experience of this disorder.
First consult your Doctor , you may need anti-depressants,counseling or may have something other than SAD, get it properly diagnosed first.
Expose yourself to direct sunlight for at least 20mins daily. This can be achieved from sitting by a window, from being outside, taking a walk, sitting in the garden, going to work,shops etc.
Take Vit D supplements or eat foods rich in Vitamin D
Some recommend special types of sunlamps for UV exposure.
For more details and the science behind S.A.D see below:
http://en.wikipedia.org/wiki/Seasonal_affective_disorder
"Various etiologies have been suggested. One possibility is that SAD is related to a lack of seratonin, and serotonin polymorphisms could play a role in SAD, although this has been disputed. "
"Subsyndromal Seasonal Affective Disorder is a milder form of SAD experienced by an estimated 14.3% vs. 6.1% of the U.S. population. The blue feeling experienced by both SAD and SSAD sufferers can usually be dampened or extinguished by exercise and increased outdoor activity, particularly on sunny days, resulting in increased solar exposure.Connections between human mood, as well as energy levels, and the seasons are well-documented, even in healthy individuals."
http://www.ploscompbiol.org/article/info:doi%2F10.1371%2Fjournal.pcbi.0040004
"Serotonin (5-hydroxytryptamine [5-HT]) is a neuromodulator that appears to play a critical role in a wealth of psychiatric conditions, including depression, anxiety, panic, and obsessive compulsions. However, despite the importance of serotonergic pharmacotherapies, notably selective serotonin reuptake inhibitors (SSRIs), the roles that serotonin plays in normal and abnormal function are still mysterious."
http://www.ncbi.nlm.nih.gov/pubmed/17138809?dopt=AbstractPlus
"CONCLUSIONS: In a cross-section of older adults, vitamin D deficiency was associated with low mood and with impairment on two of four measures of cognitive performance."
