Overview of Winter Blues

Winter Blues is usually defined as recurrent fall or winter mood & energy problems that remit in the spring or summer. Winter Blues sufferers experience increased appetite, weight gain and hypersomnia. Winter Blues was first discovered by the National Institute of Mental Health and reported inArchives of General Psychiatry in 1984.¹

What Causes Winter Blues?

As opposed to major depression and other affective disorders, scientists believe Winter Blues is a neurochemical problem² brought about by shortened winter days. Because day length causes Winter Blues, and because the timing of light therapy is critical for remission, researchers believe that Winter Blues is a result of circadian rhythm problems. This basis in chronobiology stems from the fact that morning light has a much greater antidepressant effect, suggesting a phase delay of the shortened photoperiod. As a result, the 'Circadian Phase-Shift Hypothesis' is the best explanation and predictor for treating Winter Blues.

Melatonin and Winter Blues

Most scientists believe that darker winter days cause a circadian shift in the production of melatonin and may cause melatonin to be overproduced.³ This imbalance is a main reason why people feel down and lack energy in the winter. Because light effectively suppresses melatonin, and because melatonin suppression is an indication of shifted circadian rhythms, light is believed to be the most effective means for treating Winter Blues.

Mechanism of Light

Light has been shown to be an ocular reaction. Light enters photoreceptors in the retina of the eye, which stimulate direct neural pathways, such as the retino-hypothalamic tract, to the Suprachaismatic Nucleus, located in the hypothalamus in the brain. The SCN in turn signals the pineal gland to stop the production of melatonin, as well as initiating other endocrinergic cycles.⁴ Recent findings have also shown that a specific bandwidth of light is responsible for the suppression of melatonin,⁵ and some companies are working to develop more effective products based on this research.

Prevalence of Winter Blues

An estimated 14%, or 25 million may suffer from Winter Blues. The incidence of Winter Blues is dependant on latitude. Northern areas experience shorter winter days and thus proportionately higher rates of Winter Blues. The incidence of Winter Blues may be less than 2% in Florida while 10% of northern states may suffer from Winter Blues.