Whoa, back this bus up, partner.
First, the article claims that the research shows there is no clear link between Vit D levels and SAD. Then, in the next to last paragraph, there’s this contradiction:
“Dr Franco said his study did not evaluate whether the depressive symptoms were seasonal and suggested more studies needed to be done.”
So, which is it?
Well, it could be that Vitamin D is not the mechanism that has the benefit. Or that their supplement isn’t equal to getting Vitamin D through sunlight.