I've got to wonder about correlation vs causation.
Normally, as well as food sources, your body naturally produces Vitamin D as a reaction to sunlight (being outdoors), and not having sufficient time outdoors, especially in a pleasant/nature environment, may be contributing to depression.
Normally, as well as food sources, your body naturally produces Vitamin D as a reaction to sunlight (being outdoors), and not having sufficient time outdoors, especially in a pleasant/nature environment, may be contributing to depression.