D2 <8

[CW12]

My D3 level was 90 but my D2 level was <8. What does this mean. Do I need to supplement with D2... is there such a thing. Thanks

[fbirder]

I've never heard of measuring them separately.

"In your bloodstream, vitamin D2 and vitamin D3 are changed into a form of vitamin D called 25 hydroxyvitamin D, also known as 25(OH)D. A vitamin D blood test measures the level of 25(OH)D in your blood. Abnormal levels of vitamin D can indicate bone disorders, nutrition problems, organ damage, or other medical conditions."

medlineplus.gov/lab-tests/v...

[helvella in reply to fbirder]

Quite a number of NHS labs show D2, D3 and total results. Over on Thyroid UK it has been quite a regular question.

One NHS lab in particular sells its testing online and says:

We use the latest LC-MS/MS equipment to measures D3 and D2 to give a ‘Total Vitamin D’ level.

vitamindtest.org.uk/index.html

[fbirder in reply to helvella]

Ah. You live and learn.

Is there an advantage to knowing individual results?

[helvella in reply to fbirder]

I'm not sure.

There have been suggestions that D3 is preferable but it is a long time since I really looked. UK focus is mostly D3 so I haven't really been bothered, to be honest.

I suppose if you are drinking ultraviolet treated milk and taking lanolin-derived capsules, it would help to identify how much you are getting from each.

Last one I had done, my D2 was at or near zero.

I guess that the very technique LC-MS/MS probably means that D2 and D3 results drop out separately so why not report? Other than this ongoing confusion, I rather agree with passing on all the info.

[helvella]

D2 is formed when they use ultraviolet on milk, for example. That is why in the USA, where that is near-standard, D2 levels tend to be higher.

Nowadays most D supplements are D3. Though those derived from fungi are (usually) D2.

D supplements from animal sources (e.g. lanolin) are D3.

There has been research on the two forms and whether they are equally good - I leave you to check that out as it is complicated.

What matters is total.

[CW12 in reply to helvella]

So if my total is a healthy number then the D2 doesn’t matter if D3 is ok?

[helvella in reply to CW12]

So far as I know, in deciding whether or not to supplement (or use UV lamp, or whatever), the only one that matters is total.

D2 and D3 numbers, in themselves, do not matter - just that total is achieved by adding them together!

[CW12 in reply to helvella]

Thank you