Update July 2017:
2,000 IU did not reduce the number of infections during the entire 4 month trial
VitaminDWiki suspects that only a few of the children achieved a good level of vitamin D by the 4th month
The trial, however. appears to have measured the amount of infections during the entire time, not just the last month
Since the infections during the entire 4 months were not reduced, vitamin D did not help.
JAMA charges to see the PDF
DO IT Trial: vitamin D Outcomes and Interventions in Toddlers
- a TARGet Kids! randomized controlled trial.
BMC Pediatr. 2014 Feb 8;14(1):37.
Maguire JL, Birken CS, Loeb MB, Mamdani M, Thorpe K, Hoch JS, Mazzulli T, Borkhoff CM, Macarthur C, Parkin PC.
Vitamin D levels are alarmingly low (<75 nmol/L) in 65-70% of North American children older than 1 year. An increased risk of viral upper respiratory tract infections (URTI), asthma-related hospitalizations and use of anti-inflammatory medication have all been linked with low vitamin D. No study has determined whether wintertime vitamin D supplementation can reduce the risk of URTI and asthma exacerbations, two of the most common and costly illnesses of early childhood. The objectives of this study are: 1) to compare the effect of 'high dose' (2000 IU/day) vs. 'standard dose' (400 IU/day) vitamin D supplementation in achieving reductions in laboratory confirmed URTI and asthma exacerbations during the winter in preschool-aged Canadian children; and 2) to assess the effect of 'high dose' vitamin D supplementation on vitamin D serum levels and specific viruses that cause URTI.
Methods/design: This study is a pragmatic randomized controlled trial. Over 3 successive winters we will recruit 750 healthy children 1-5 years of age. Participating physicians are part of a primary healthcare research network called TARGet Kids! Children will be randomized to the 'standard dose' or 'high dose' oral supplemental vitamin D for a minimum of 4 months (200 children per group). Parents will obtain a nasal swab from their child with each URTI, report the number of asthma exacerbations and complete symptom checklists. Unscheduled physician visits for URTIs and asthma exacerbations will be recorded. By May, a blood sample will be drawn to determine vitamin D serum levels. The primary analysis will be a comparison of URTI rate between study groups using a Poisson regression model. Secondary analyses will compare vitamin D serum levels, asthma exacerbations and the frequency of specific viral agents between groups.
Identifying whether vitamin D supplementation of preschoolers can reduce wintertime viral URTIs and asthma exacerbations and what dose is optimal may reduce population wide morbidity and associated health care and societal costs. This information will assist in determining practice and health policy recommendations related to vitamin D supplementation in healthy Canadian preschoolers and place Canada at the forefront of pediatric vitamin D health outcomes research.
Study First Received: August 2011
Estimated Primary Completion Date: May 2014
Estimated Study Completion Date: September 2014
PDF is attached at the bottom of this page
Rough HTML of the study is at the end of this page
A tiny number of people get even the "minimum wage" of vitamin D (orange line)
Anticipate great success from this Random Controlled Trial based on scores of previous studies
See also VitaminDWiki
- Children helped by 2,000 IU of vitamin D, but not RDA amount (600 IU) – RCT Sept 2017
- Upper respiratory tract infection 2X more likely if vitamin D less than 30 ng – Aug 2013
- Respiratory infections reduced by 63 percent with 4000 IU vitamin D daily - RCT Dec 2012
- Vitamin D and Respiratory Tract Infections – meta-analysis with charts June 2013
- 100 percent of Acute Respiratory Failure patients had low vitamin D - April 2012
- Acute respiratory infection treated by vitamin D in 6 of 12 clinical trials – review Nov 2012
- Fewer respiratory infections if optimal level of vitamin D (more than 47 ng) – Sept 2013
- Breathing category listingm which includes searches such as the following
Search VitaminDWiki for RTI OR "Respiratory Tract Infection"
- Overview Asthma and Vitamin D there were 30 intervention trials for Vitamin D and Asthma as of Feb 2014,
Overview of Asthma and Vitamin D includes the following chart
5X less likely to be hospitalized for Asthma if adequate vitamin D