50,000 IU of vitamin D monthly in winter gets most above 20 ng – RCT Nov 2013

A Double-Blind, Placebo Controlled, Randomized Trial to Assess the Impact of a Monthly Administration of 50,000 IU of Vitamin D3 for 6 Months on Serum Levels of 25-Hydroxyvitamin D in Healthy Young Adults.

Int J Endocrinol. 2013;2013:652648. doi: 10.1155/2013/652648. Epub 2013 Nov 13.
Brunel E, Schnitzler M, Foidart-Dessalle M, Souberbielle JC, Cavalier E.

In this double blind, unicentre, randomized, placebo controlled study, we evaluated the changes in 25-hydroxyvitamin D (25(OH)D) serum levels in 150 young Belgian adults (18-30 years), monthly supplemented with 50,000 IU of vitamin D (VTD) or placebo for 6 months, from November 2010 to May 2011. At T0, 30% of the population presented 25(OH)D serum levels below 20 ng/mL. In the VTD-treated group, mean serum levels increased from 21.2 ± 8.2 to 30.6 ± 8.8 ng/mL (P < 0.001) at T3mo and to 36.0 ± 9.2 ng/mL (P < 0.001) at T6mo. Despite documented VTD intake, no changes in serum levels were, however, observed in 10% of the treated group. In the placebo group, mean 25(OH)D serum levels decreased from 22.8 ± 8.5 to 14.0 ± 6.9 ng/mL at T3mo (P < 0.001) but returned to values not significantly different from those observed at T0 (23.5 ± 8.6 ng/mL) at T6mo. No difference between serum calcium levels was observed between the groups throughout the study. In conclusion, monthly supplementation with 50,000 UI of VTD in winter can warrant serum 25(OH)D levels above 20 ng/mL in 96.2% of those healthy young adults without inducing unacceptably high 25(OH)D concentration.

This supplementation is safe and may be proposed without 25(OH)D testing.

Clipped from PDF
Interestingly, we found that 4 participants (about 3%) did not respond to vitamin D supplementation as they did not increase their 25(OH)D levels in May.
These patients might of course have been poorly compliants, even if we registered their intakes and if they confirmed their good compliance.
They might also suffer from intestinal fat malabsorption, Crohn disease, or inflammatory bowel disease [22] even if the prevalence (13%) seems too high.
This observation is interesting because it shows that the response to vitamin D is individual and can be affected by different reasons.

50000 IU monthly @ is.gd/50000monthly

PMID: 24324493
PDF is attached at the bottom of this page


See also VitaminDWiki

Chart of Vitamin D levels vs disease - Grassroots Health June 2013 has the following (many people want more than 20 or 30 ng)
derived from Grassroots 2013

Summary of 8 studies: notice that 1700 IU (50,000 monthly) would get average to about 36 ng
     click on chart for details
Response - 8 studies  bit.ly/16TuWp5

Short url = http://is.gd/50000monthly

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