Don't really know wether to put this in the autoimmune or hormonal subforum
Started supplementing 3000iu vitamin D3 about a week ago. Haven't had my levels checked but I'm sure that I'm deficient because of where I live and what I do. Vit D is something most people seem to lack, because you see it talked about everywhere especially around winter time, and its supposed to be important for especially immune function.
However, after an O rather than improve that my symptoms got worse and have taken longer to go away. I've thought about this before when considering trying other supplements that there's always a delicate interplay and a fine balance of other micronutrients that have to be considered. I didn't in the case of vitamin D, which is not to say that I didn't need it, but rather that what supplementing it depletes might be a key in remedying POIS.
From what I can gather it's mainly magnesium but also vitaminK and vitamin A. These in turn have their own effects on other substances, like magnesium on zinc. I've seen magnesium pop up on the forum but not quite sure what the consensus is, and if there is one, if people have considered looking at the relationship with other nutrients. I'm not an expert but I generally think that it's better to aim for balance than just taking benefits of individual supplements at face value. Something's amiss and it'd be nice if the missing piece was the same for most of us but megadosing one or a couple of things (in the case of vit D many go way higher and what I took is already a couple of times the RDI which varies between countries) is in my opinion unlikely to work.