800 IU (20 mcg) per day increases vitamin D blood levels 8 ng/ml (20 nmol/L). 1000 IU (25 mcg) per day increases vitamin D blood levels 10 ng/ml (25 nmol/L). 2000 IU (50 mcg) per day increases ...

According to one older review, many experts agree that at least 1,000 IU (25 mcg) of vitamin D3 daily is needed in situations where there is no exposure to sunlight. Because vitamin D is fat ...

Moderate and high doses of vitamin D3 daily for 5 years didn’t reduce the risk for type 2 diabetes in healthy older adults ...