There have been several studies linking low Vitamin D levels to depression. A meta analysis found improvement when supplements were taken.
One could say depressed people stay in bed all day and don't go outside and get sunlight, thus low vit d
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.
Link between Vitamin D and depression has been known for a long time. It is not a new finding.
> 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.
At higher latitudes, it is extremely difficult to produce Vitamin D from sunlight unless you expose your entire torso(without a shirt). If you have dark skin, you need 2x or 3x more time.
Again, there is extensive literature on this, you just have to read it instead of speculating.
The link has been disputed for as long.
> Again, there is extensive literature on this, you just have to read it instead of speculating.
There you go:
https://pmc.ncbi.nlm.nih.gov/articles/PMC4008710/
"Although low vitamin D levels have been observationally associated with depression and depressive symptoms, the effect of vitamin D supplementation as an antidepressant remains uncertain."
I'm not saying you should stop taking it. If it works for you - great. But don't get annoyed at people who point out that the link is tenuous at best.
(Incidentally, it did nothing to improve my mood - but I continue to take it for its other health benefits. I was in the severe depletion zone, and brought it up to mid-normal.)
I am not sure whether they compensated for BMI or used sufficient dosage. A 2000 IU/day might not be sufficient as the amount required depends on the current level and BMI.
From studies we know, Vitamin D accumulates in fat cells before it is available for bodily functions, so unless the dosage was adjusted for BMI, the experiment might not have been done on an equal footing for all participants.
How do we know that Vitamin D accumulates in fat cells? When someone loses weight, the Vitamin D level improves dramatically despite not having ingested any Vitamin D or made from sunlight.