The years of 2020 and 2021 have been difficult ones, due to the worldwide response to a deadly pandemic. Staying inside, foregoing outside activities, spending the entire 2020 summer in apartments, working from home, ordering in groceries, all of it has changed our bodies’ natural seasonal cycles. It has also brought an epidemic of S.A.D., also known as Seasonal Affective Disorder, even during months of full sun.
S.A.D. was first identified by its symptoms and named in 1981. Now recognized by the National Institute of Mental Health as a mental health disorder, it was studied extensively in Scandinavian countries that experience short days and little sun during winter. There were higher incidents of debilitating depression, suicides and other serious changes in mood that affected people in winter and usually lifted during spring.
What causes Seasonal Affective Disorder? Doctors originally thought the depressive symptoms were psychiatric illnesses. Then innovative doctors began studies using full-spectrum bright light (the light that comes from the sun) to treat one group and dim yellow light to treat another group (N.E. Rosenthal and T.A. Wehr, “Seasonal Affective Disorders,” Psychiatric Annals 17, no. 10 (Oct. 1987): pp. 670-674). The results were remarkably clear. Humans need sunlight for many reasons, all associated with physiological functioning, as well as emotional and mental balance. Seasonal Affective Disorder is caused by a lack of sunlight.
Fixing Seasonal Affective Disorder looks easy. Put yourself in sunlight. So how can you import the sun, when you need it? Maybe the question should be: how do you import sun “light”?
Since full-spectrum light is the only form of light that eradicates Seasonal Affective Disorder, search for the best full-spectrum light you can find. Now, 35 years after the S.A.D. studies, full-spectrum lighting is widely available. There are desk lights and floor lamps. There are full-spectrum light bulbs. Make sure they are truly full-spectrum, and nothing is deducted. The full spectrum includes the rainbow of visible light (colors), ultraviolet light and infrared light. Even though some of the spectrum is not visible, it is still necessary for human health. Optimum full spectrum light is still light from the sun, under the sun, outside. Window glass distorts sunlight, so that form of light is not truly full-spectrum. Sunglasses prevent you from absorbing full spectrum light. Even clear glasses block it. The only path to avoid S.A.D. is the most direct one—light, full-spectrum light–and lots of it (at least an hour a day), under the sun or under truly full-spectrum lighting.
It is not necessary to understand the entire clinical history of S.A.D. and its treatments. It is, however, important to know that you can do everything possible to ensure you are not affected by S.A.D. and you can do it in your own home. If this means sitting under a full spectrum floor lamp while watching TV, so be it.