Work out vitamin d dose instantly with clear inputs, formula shown and shareable results.
Uses the widely cited relationship that 100 IU of vitamin D3 daily raises 25-hydroxyvitamin D by about 1 ng/mL, and adds a weight-adjusted maintenance dose.
Vitamin D repletion
Daily dose (IU) = (target - current level in ng/mL) x 100; maintenance is 1,000 to 2,000 IU/day, higher in obesity
Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.
Vitamin D is sequestered in adipose tissue, so a larger dose is needed for the same serum rise.
4,000 IU a day is the tolerable upper intake level for adults; higher doses are used only under supervision.