Why does the Vitamin D Council recommend 5,000 IU/day?
Posted on December 10, 2013 by John Cannell, MD
Where did the Vitamin D Council get its recommendation that adults take 5,000 IU/day of vitamin D3 for the rest of their life? The Institute of Medicine’s Food and Nutrition Board say 600 IU/day is enough for adults and the Endocrine Society says 2,000 IU/day is enough for most adults.
We think the safest thing to do while all the research is going on is to maintain natural vitamin D levels. By natural, we mean those levels obtained by those with natural sun exposure, such as lifeguards, some roofers and gardeners, and others who work in the sun and expose a lot of skin to sunshine. This is how our ancestors behaved throughout our evolutionary history.
The best study that examined the vitamin D levels of people who get plenty of sun exposure was published last year. Researchers discovered that free-living hunter gatherers living around the African equator (where humans evolved) have average vitamin D levels of 46 ng/ml (115 nmol/L).
- Luxwolda MF, Kuipers RS, Kema IP, Dijck-Brouwer DA, Muskiet FA. Traditionally living populations in East Africa have a mean serum 25-hydroxyvitamin D concentration of 115 nmol/l. Br J Nutr. 2012 Nov 14;108(9):1557-61.
Most people will not have their blood tested unless their doctor recommends it. So we needed a recommended dose that:
- Is easy to obtain at most pharmacies.
- Will get at least 97% of people above 30 ng/ml.
- Will get most people above 40 ng/ml, and close to around 50 ng/ml.
- Will not cause anyone to get toxic levels.
When we decided on a recommendation with the four goals above in mind, we also had to take into account body weight. Besides genetics, body weight is the single biggest determinate of vitamin D levels. The more you weigh, the more vitamin D you need to take.
Professor Robert Heaney of Creighton University details in the study below just how high vitamin D supplementation/input needs to be to reach the vitamin D level goals above.
- Drincic AT, Armas LA, Van Diest EE, Heaney RP. Volumetric dilution, rather than sequestration best explains the low vitamin D status of obesity. Obesity (Silver Spring). 2012 Jul;20(7):1444-8. doi: 10.1038/oby.2011.404.
Together with his coauthors, Professor Heaney stated that for a normal weight adult, 5,000 IU/day of total input was needed to obtain a vitamin D level of 40 ng/ml. Of course the final vitamin D level obtained by any dose depends on baseline level, sun exposure and genetics. But he was speaking of the average adult.
For those who want a more careful calculation, he stated his data showed that 70-80 IU/day/kg of body weight total input is needed to obtain a 25(OH)D of 40 ng/ml. That works out to about 35 IU/day/pound. So a 100 pound woman would need 3,500 IU/day of total input but a 300 pound lineman would need 10,500 IU/day. Keep in mind this is total input, which includes sunlight, diet and supplements.
Taking all these factors into account, we conclude a recommendation of 5,000 IU/day is about right for the average adult.
See also VitaminDWiki
- Low cost cofactors for vitamin D Cofactors are vital when taking > 3,000 IU of vitamin D
- Vitamin D3 for Vegans
- Low Cost vitamin D - including liquid and bulk
- Patients older than 65 needed 5,000 IU vitamin D – May 2010
- USANA recommended 5,000 IU to achieve 50 ng/ml with graph
- Vitamin D Recommendations around the world - IU and ng which has the following chart
Response to Vitamin D: summary chart of 8 studies – March 2013 shows 5,000 IU dose would get avg of 60 ng
Is 50 ng of vitamin D too high, just right, or not enough has
Chart from GrassRootsHealth shows that response to 5,000 does not vary much with the form
See also web
- Amazon US 400+ listings for 5,000 IU of vitamin D as of Dec 2013: Capsule, liquid, gummy bear, Kosher, Halal, etc.
- D3Plus: The only Vitamin D on the market endorsed by the Vitamin D Council
5,000 IU vitamin D + 8000 ug Vitamin K + 225 mg Magnesium + 12 mg Zing + 3 mg Boron (3 capsules/day due to the Magnesium)
comment by VitaminDWiki - excellent combination of D with cofactors