Role of Vitamin D in Children
- Benefits of vitamin D in children
- Which children are at risk of vitamin D insufficiency?
- At what age can you take vitamin D supplements?
The requirement for vitamin D begins from the foetal stage, continues during childhood and throughout life.
During pregnancy when foetal bones are developing, calcium is deposited into bones, making them strong. This is where vitamin D plays an essential role; vitamin D is needed for normal metabolism and utilisation of calcium and aids in the mineralisation of bone. During pregnancy, maternal vitamin D requirements can increase up to four-to five-fold to facilitate the availability of the extra calcium required for fetal skeletal growth.1
In children, adequate vitamin D levels are essential to normal development. In particular, vitamin D is crucial for normal growth and development of bones and teeth.2
In addition to bone health, vitamin D also has an effect on language development. In 2011 results became available from a large clinical trial investigating vitamin D levels in pregnancy and offspring development. A total of 743 offspring from mothers from Perth, Western Australia were investigated. This study found that vitamin D insufficiency among Caucasian women during pregnancy was associated with an increased rate of language impairment among offspring. It concluded that maternal vitamin D supplementation during pregnancy may reduce the risk of developmental language difficulties among their children.3
Vitamin D plays many additional roles in the body. In children as well as adults, it helps regulate heartbeat, protects against muscle weakness and is needed for normal blood clotting and healthy thyroid function. In addition, vitamin D supports immune function which keeps us strong and able to fight off colds and flues.2
Children who do not receive adequate sun exposure may be at risk of vitamin D insufficiency.5 This group includes children who cover up for sun protection or for religious or cultural reasons.
Geographical location may play a part in how much vitamin D a child receives from the sun e.g. a study found that 68% of 16-year old males in Tasmania are vitamin D insufficient (<50 nmol/L).4
Breastfed infants of dark-skinned or veiled women are another group at risk of vitamin D insufficiency. This is because an infant relies on the mother’s milk for much of their vitamin D however dark-skinned or veiled women are at a higher risk of being vitamin D insufficient.
Dark skinned children are also at risk of vitamin D insufficiency. Dark skins naturally contain more melanin and this impedes vitamin D synthesis.5
A diet low in vitamin D foods may also contribute to a insufficiency of vitamin D.5 However it should be noted that it is unlikely that diet alone provides sufficient vitamin D intake – most Australians only get around 10% of their vitamin D from dietary sources.6
Vitamin D is considered a suitable supplement for all ages providing the label dosage is adhered to. It is advised to discuss supplementation with your GP if your child is taking medications as vitamin D may interact with some medications.7
The National Health & Medical Research Council (NHMRC) vitamin guidelines advise the adequate intake for infants, children and adolescents is 5 mcg/day (200IU/day) assuming there is little to no exposure to sunlight.8 If your child is at risk of a vitamin D insufficiency it may be beneficial to provide them with daily vitamin D supplementation.