Implications for 25-Hydroxyvitamin D testing of public health policies about the benefits and risks of Vitamin D fortification and supplementation

Scandinavian Journal of Clinical & Laboratory Investigation
April 2012, Vol. 72, No. S243 , Pages 144-153
Reinhold Vieth
Department of Nutritional Sciences and Department of Laboratory Medicine and Pathobiology, University of Toronto, and Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Canada M5G 1X5,
Correspondence: Reinhold Vieth, Department of Nutritional Sciences and Department of Laboratory Medicine and Pathobiology, University of Toronto, and Pathology and Laboratory Medicine, Mount Sinai Hospital, 600 University Ave Toronto, Ontario M5G 1X5 Canada. E-mail: rvieth at mtsinai.on.ca

Probably presented at the Bermeyer Coonference in Garmishpartenkirchen (Germany) in March 2012

Vitamin D status is of interest to physicians caring for patients in poor general health. The tool for assessing vitamin D status is the serum 25-hydroxyvitamin D (25(OH)D) concentration. Based on clinical trials and epidemiology the low end of the desirable concentration of this analyte generally ranges from 50 nmol/L to 75 nmol/L. Based on clinical trials, the high end of the safe concentration for 25(OH)D is at about 225 nmol/L, with an unspecified margin of safety beyond that.

In the absence of sunlight, 225 nmol/L is achieved with prolonged consumption of about 10,000 IU/day (250 ?g/day) of vitamin D3.
Hence that intake should be regarded as safe, and in the absence of sunshine, comparable vitamin D-wise to abundant sun exposure.

Government policy is very conservative, and consequently, the latest advice from the Institute of Medicine for Canada and the USA specifies that in the absence of sunshine, a recommended dietary allowance (RDA) of 600 IU/day (15 ?g/day) of vitamin D will provide a serum 25(OH)D concentration of at least 50 nmol/L.

Dietary-vitamin D-intake statistics for adult populations show that average intakes from food and supplements are 200–400 IU/day (5–10 ?g/day), respectively.

Therefore, adult populations are consuming vitamin D in amounts far below the RDA.

Even if adults were to consume the RDA for vitamin D, it would still not be enough to ensure 25(OH)D >?50 nmol/L.

The implication of all these things for the clinical laboratory is that there will continue to be a demand for 25(OH)D measurements for many years to come.

Total vitamin D intake from food and supplements for males and females

Median never gets to 400 IU

PDF is attached at the bottom of this page

See also VitaminDWiki

• Safety Issues of Vitamin D Supplementation – Jan 2013
• Vitamin D and UV safe and toxic doses - Veith 1999
• Pharmacology of vitamin D - April 2011
• As much as 10000 IU vitamin D is safe – review April 2012
• Name a rat poison crucial to health and safer than water
• Overview Vitamin D Dose-Response
• Zero Deaths from Vitamins Minerals Amino Acids or Herbs - Jan 2011
• There has never been a death due to excessive vitamin D yet there were 56 deaths per year from NSAIDS
• Overview Toxicity of vitamin D which has the following chart

short URL = http://is.gd/dveith2012