The sunshine vitamin may play a greater role in placating Seasonal Affective Disorder than previously thought, researchers now say. Earlier research and common sense have long suggested a relationship between sunshine, vitamin D and SAD, but evidence now shows that vitamin D likely regulates the condition, according to researchers from the University of Georgia, University of Pittsburg and Queensland University of Technology.
“Rather than being one of many factors, vitamin D could have a regulative role in the development of SAD,” said Alan Stewart of the University of Georgia College of Education in a news release.
Evidence from more than 100 leading articles reviewed by the researchers suggests multiple mechanisms by which vitamin D regulates SAD. The 8-week time period between peak in intensity of sunlight and the onset of SAD correlates with the time it takes the body to process UV light into vitamin D. Vitamin D also affects the synthesis of serotonin and dopamine, both of which are biologically connected to depression.
“Evidence exists that low levels of dopamine and serotonin are linked to depression, therefore it is logical that there may be a relationship between low levels of vitamin D and depressive symptoms,” Michael Kimlin, a Cancer Council Queensland Professor of Cancer Prevention Research said in the press release. “Studies have also found depressed patients commonly had lower levels of vitamin D.”
Dr. John Cannell of the Vitamin D Council (VDC) recommends still spending some time outside for UVA light this time of the year as well as using alternative sources, like a UV light or sunbed, for UVB.