I think it depends on the person. If you get your blood level checked when you have a regular physical, you can adjust the dose as needed to keep the level where you want it (I shoot for the upper end of the normal range, and 5000 IU a day seems to be doing that for me).
I think it depends on the person. If you get your blood level checked when you have a regular physical, you can adjust the dose as needed to keep the level where you want it (I shoot for the upper end of the normal range, and 5000 IU a day seems to be doing that for me).