Vitamin D Status of Newborns Study (Recruiting)





Goals of the research

This research study will examine if giving vitamin D supplements immediately after birth to infants, who are born with a low vitamin D status, will help them build muscle and to normalize growth by 3 months of age and maintain it up to 3 years of age, compared to a reference group of infants born with adequate vitamin D status.


Importance of the research

One in four infants is born with low amounts of vitamin D stored in their body.

Vitamin D is essential for the growth of strong healthy bones.  There is also evidence that vitamin D supports a leaner body.

Health Canada recommends that all infants receive 400 IU of vitamin D each day. More vitamin D may be needed to improve levels in infants born with low vitamin D.


What will happen in this research study?

In this study, infants with low vitamin D at birth will be given either the regular amount of supplementation (400 IU) or a higher amount (1000 IU) to more quickly build up the vitamin D stores in the body.  Infants with adequate vitamin D levels will be provided with the regular amount of supplementation (400 IU).  All supplements have been approved by Health Canada.

Infants will be measured for growth, as well as, muscle and fat mass during the first year of life and into the toddler years.

At each visit (1 week, 3, 6, 12, 24 and 36 months of age) we will:
  • Measure your infant’s weight, length and head size (5 min);
  • Perform a bone mineral density scan on your infant’s whole body, spine and arm bone. This scan uses a very low dose of x-rays and will allow us to measure your infant’s bones, lean mass and fat mass.  The scan is best done if the infant is asleep on their back.  Rest assured you can stay with your infant the entire time (10 min);
  • Collect 1 ml (1/5 of a teaspoon) of blood by venipuncture and a urine sample.  The blood and urine tests will allow us to measure vitamin D levels, calcium concentrations and other tests that tell us how the bones are developing (5 min);
  • Ask questionnaires (15 min);
  • At the first visit only we will collect a 5 ml fasting venous blood sample from both the mother and father, if possible, to test your vitamin D concentrations (10 min);
  • At the first visit only we will measure mother’s weight, height and body fat % (5 min).


For how long will you participate in this study?

The study will begin when your baby is approximately 1 week old and continue until he/she is 3 years of age.  There is a total of 6 study visits.