I tested as mildly deficient when I moved far North for a job. I'm native, so my skin color didn't help but they get a lot less sun up here. I've never been so pale in my life, lol.

I started taking a D3 and K2 supplement and a year later on my next test I tested in the normal range. Didn't notice any changes from taking the supplement, but it probably doesn't hurt to have it in my body if my body needs it.

That being said, I would test. No sense in having too much.

There was a nice HN discussion about an M.D.'s blog re: Vitamin D that includes some notes about toxicity. The doctor showed-up on HN and interacted in the comments, too. I found what she wrote to be valuable.

https://news.ycombinator.com/item?id=24138590

Something interesting to me here: "Darker skin" as a standalone term implicitly means white skin is the baseline. We pretty much only see "lighter skin" or "paler skin" when it's in a comparison. We do see the absolute of "pale skin".

How do you like Mito?

Is there an non-lab way to know if you're vitamin D deficient?

came here to say the same thing; a family member was made unwell by taking vitamin D supplements for something else minor. Nothing bad and stopped immediately.