Vitamin D3 Safety

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Therefore, the Institute of Medicine has set the UL for adults at 100 μg/d, and the adequate circulating 25(OH)D level at 50 to 125 nmol/l. In clinical practice, oral vitamin D dosing has to consider that the increment in circulating 25(OH)D depends on baseline 25(OH)D levels and the person’s body weight. It is reasonable to assess 25(OH)D before and 3-6 months after initiation of oral vitamin D administration and to adjust the dose, if necessary.

In Future, Two Issues Have To Be Clarified: First, Would It Be More Appropriate To Define Instead Of A Fixed Ul A Variable Ul, Based On The Individual’S Body Weight?

Second, what are the underlying mechanisms, if any, for potentially harmful vitamin D effects at circulating 25(OH)D levels between 125 and 375 nmol/.

Recent Blog Articles

Ing too much vitamin D can cloud its benefits and create health risks

December 15, 2019


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Objective: Our objective was to assess the efficacy and safety of prolonged vitamin D 3 intakes of 25 and 100 μg (1000 and 4000 IU)/d. Efficacy was based on the lowest serum 25-hydroxyvitamin D [25(OH)D] concentration achieved by subjects taking vitamin D 3 ; potential toxicity was monitored by measuring serum calcium concentrations and by calculating urinary calcium-creatinine ratios.
Serum 25(OH)D was measured by radioimmunoassay. Serum calcium and urinary calcium excretion did not change significantly at either dosage during the study. Conclusions: The 100-μg/d dosage of vitamin D 3 effectively increased 25(OH)D to high-normal concentrations in practically all adults and serum 25(OH)D remained within the physiologic range; therefore, we consider 100 μg vitamin D 3 /d to be a safe intake.

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We review the alternatives of vitamin D supplementation through dietary, other natural supplements as well as sunlight therapy, in an evidence-based manner.

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