An update. (I don't want to hog this thread! But what I'm experiencing is a little hard to understand though I'm not at all worried about it. :))
On 6 January, a month ago, I did a purely routine blood test and found, to my surprise, that my Vitamin D level was way too low, at 22.66.
I immediately started taking 10,000 IU of Vit D3 a day from a bottle I'd had on the shelf and not used before. (I'd actually ordered it by accident over a year ago. Looking carefully now at the label, the expiry date was Dec 2024.).
I tested it again on 16 Jan, and it had sunk to 17.34. (OMG!)
Dennis observed that I was a walking human petri dish. :P He explained about Vitamin K2, which I doubled per day immediately.
Two days ago I tested it again, confident that it had to be back to normal. (I'd even followed Vicus' advice and carefully! rolled up my sleeves in all but the most piercing mountain sunshine.)
But my level had crept up to merely 19.97, still lower than a month previously.
I even emailed the laboratory head (a doctor in biochemistry) and asked her to very kindly double-check the numbers. She did, and assured me that the test result was good.
So now I'm changing the brand of my D3.
I'm suspecting that with an expiry date of Dec 2024, the impressively labeled 10,000 IU capsules may have become impotent, with almost nothing in them. (Internet searches suggest D3 does lose potency over time.)
I'll test it again in a couple of weeks, after taking 2x 4000 IU capsules per day of a new brand which I've just bought locally.
So, in summary:
No need to reply, or express any concern! All is well. I'll update again here in a couple of weeks, just in case this might be of any value to anyone out there.. :)
- I'm not worried about this at all. I feel fine in every way. It's merely an odd mystery to solve.
- If it's the brand or the bottle that's the problem (actually delivering little or nothing!), that'd be quite a lesson to learn.
- The whole thing does make me wonder what unknowns might be lying in potential ambush for those many people who never have a blood test of any kind and might have no idea what's out of balance.

