Those Winter Blues might be Seasonal Affective Disorder
What is SAD exactly?
Much like clinical depression, SAD symptoms can include:
low energy
loss of interest in things you previously enjoyed
sadness
irritability
difficulty sleeping
change in appetite
feeling sluggish
difficulty concentrating
feeling hopeless
suicidal thoughts
Why is SAD more prevalent during the winter months?
People who experience SAD might have difficulty regulating the neurotransmitter serotonin, which is linked our moods.  SERT is a protein that helps regulate serotonin levels. Studies have revealed through PET scans that a slight variation in SERT levels in people with SAD is present compared to those without. Sunlight has been shown to maintain low levels of SERT.  During the darker winter months a person with SAD produces higher amounts of SERT and therefore will have lower levels of serotonin in the brain. Lower serotonin levels is correlated with depressive symptoms.
Melatonin is another neurotransmitter that may also contribute to SAD symptoms. This hormone helps regulate sleep. Increased exposure to darkness increases the body’s levels of melatonin, therefore leading to increased feelings of sleepiness and lethargy.
Both serotonin and melatonin can impact your circadian rhythm – further aggravating sleeping patterns during the winter for those with SAD.
Good news!
SAD can be treated with a combination of phototherapy, medication, counseling, supplementing with vitamin D, magnesium, same-e, and getting regular amounts of exercise. Proper nutrition can help you maintain your vitamin levels, but supplementing is also an option. It has also been shown that exercise, especially exercising to fatigue can help increase the rate of serotonin synthesis, combating SAD. As always please consult with a physician before beginning any treatment.