Debbie Nicholson

The two most important factors in determining vitamin D levels in a child’s body

A new study reveals vitamin D supplements and consuming cow’s milk are the two most important ingredients that determine how much vitamin D is in a child’s body.

Dr. Jonathon Maguire, MD, FRCPC, MSc, pediatrician and researcher at St. Michael's Hospital, assistant professor, Departments of Pediatrics and Health Policy, Management and Evaluation, University of Toronto and author of the study said those ingredients play a bigger part than skin color and sun exposure.

Vitamin D deficiency is a risk factor for a number of illnesses, including asthma, allergies, Rickets and increased incidence of risk factors for cardiovascular problems such as heart attack and stroke.

Dietary records of Canadian infants show that at 12 months they are receiving only 11 percent of their recommended daily allowance of vitamin D through food such as oily fish, fortified dairy products and cereals. In the US, around 70% of kids have low levels of vitamin D.

For the study, Dr. Maguire examined vitamin D tests of 1, 898 healthy children ages one to five years from December 2008 to June 2011, who participated in TARGet Kids (The Applied Research Group for Kids!), a unique collaboration between children's doctors and researchers from St. Michael's Hospital and The Hospital for Sick Children. The program follows children from birth with the aim of preventing common nutrition problems in the early years and understanding their impact on health and disease later in life.

The results revealed that two factors were significantly linked with higher vitamin D stores (Vitamin D is a fat-soluble vitamin, meaning the body can store it in the liver and fatty tissue) in children under the age of six. The two factors were taking a daily vitamin D supplement and drinking two cups of cow’s milk a day. Both of those factors were better at foretelling vitamin D stores in children instead of skin color or sunlight exposure assessment.

According to Dr. Maguire in order to keep adequate vitamin D stores in children it is done through dietary intake of vitamin D by the use of supplements and cow’s milk. Dr. Maguire notes he was surprised that 57% of the children were taking regular vitamin D supplements. He believes this could be due to parent’s hearing evidence about supplements through the media.

In the conclusion, Dr. Maguire writes: “Two modifiable dietary intake variables (vitamin D supplementation and cow's milk intake) are the most important determinants of 25-hydroxyvitamin D status in early childhood.”

Dr. Maguire further states: “Early childhood is a critical stage in human development, so achieving and maintaining optimal vitamin D levels in early childhood may be important to health outcomes in later childhood and adulthood.”

In case you’re wondering how much milk you should give your children, Dr. Maguire and his research team have the answer:

"We saw that two cups of cow's milk per day was enough to maintain adequate vitamin D levels for most children, while also maintaining iron stores. With additional cow's milk, there was a further reduction in iron stores without greater benefit from vitamin D," said Dr. Maguire.

This new research is published in the Archives of Pediatrics and Adolescent Medicine.

Vitamin D can also be obtained by direct sunlight. Sensible sun exposure (usually 5-10 min of exposure of the arms and legs or the hands, arms, and face, 2 or 3 times per week).


Slideshow; Sources of abundant vitamin D

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