Comment by nullc

> I took 2000IU (+K2) a day for many years in between testing my blood levels and still had <30ng/ml and had to go up to 5000IU/day.

Likewise, 23ng/ml while taking 2000iu/day of dry vitamin-d.

Switched to 5000iu +K2 in MCT oil, -- 8 months later I'm at 64ng/ml.