shayk i did not go for the full text, but i liked that someone actually published that under 100 nmol/L is insufficient!! haven't seen that number and that word together in a published article before.
The average 25(OH)D level was 71 ± 39 nmol/L (Mean ± SD), and 167(84%) patients had insufficient levels (≤100 nmol/L) of 25(OH)D.
it's interesting to me that when i started investigating my d3, my level was 72 - close to another 'ms average' if you will, like my uric acid was.
when i talked to the hospital in early 06 about getting my level up, they said the protocol they were giving me was used for people that were seriously deficient, to get them UP to the level i was currently at. i am very glad that that thinking seems to be evolving.
now as to this d3 d2 thing, i think it's already pretty well established that d3 is the more appropriate and effective, that low doses of either form don't do much, and that high doses of either would be more beneficial. also that 4000IU per day is likely what's needed per the literature, and health canada only recently bumped the recommendation from 200IU/d to 2000IU/d (at least they're meeting the science halfway), so studying the effects of 800IU/d seems pretty ludicrous to me.
from past studies i would suspect that high dose d3 gets the job done in a shorter time than d2, and in a more biologically appropriate way.