For adults, a level of vitamin D in the blood of 20 nanograms per milliliter (ng/mL) or above is generally considered adequate. Levels below 20 ng/mL are generally too low for adequate bone health ...

of vitamin D per day can raise the vitamin D blood test only 1 ng/ml or just 2.5 nmol/L after 2 to 3 months. How much vitamin D is needed per day to obtain a normal vitamin D blood level?

A 42-year-old woman with treatment-resistant insomnia discovered her vitamin D level measured just 18 ng/mL despite living in a sunny climate. After three months of supplementation bringing her ...

Other organizations define a vitamin D insufficiency as 12 to 19 ng/mL (30 to 47.4 nmol/L ... 1 to 13 years 15 mcg or 600 IU 14 to 18 years 15 mcg or 600 IU 19 to 50 years 15 mcg or 600 IU ...