@Marcus haha opps! Good catch. I ment “μm” But I typed it in a diffrent editor and the “μ” did not paste well. The maths is not affected. Does it look sound to you otherwise?
@Quidditch Yes, and actually, from what I have read, someone could safely take up to 250μg (10,000 IU) without problems.
http://www.vitamindcouncil.org/about-vitamin-d/am-i-getting-too-much-vitamin-d/
Ok, but this is a matter of data source. The WHO tend to give quite conservative estimates on safety issues, and they are my source for a 50μg maximum (see the link I provided). If we work from different studies to the studies WHO use, then we can expect different answers.
This is the point where James Collier’s expertise is invaluable. He is a pretty starry nutritionist and is far more qualified than most to say which studies are possible to rely on.
I’ll look into this and other micros 
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