How much Vitamin D do children need?

Many people believe that because we live in Australia we do not need to be concerned about our children getting enough Vitamin D. It is often thought that our sunny climate in Australia usually takes care of our Vitamin D requirements because Vitamin D is produced in our body by the action of sun on the skin. Several studies have assessed Vitamin D status in Australia. Although the prevalence of deficiency does vary, it is acknowledged to be much higher than previously thought.

Children need adequate Vitamin D as it is required to maintain calcium and phosphorus levels for healthy and strong bones, teeth and muscles. It is also essential for a healthy nervous and immune system. The amount of Vitamin D required by your child depends on certain risk factors for Vitamin D deficiency, which include:

  • Sun exposure – children may have limited sun exposure due to sunscreen, clothing that covers most of their skin, minimal outdoor playtime or illness. It is difficult to provide general guidelines on adequate sun exposure to maintain adequate Vitamin D levels, due to the various factors that influence Vitamin D. It has been suggested by some researchers that to obtain enough Vitamin D from sunlight alone during the months of October to March, 10-15 minutes of unprotected sunlight exposure outside of the hours of 10am to 3pm was enough. However, during other seasons, such as winter, up to 1 hour of exposure was needed.1 It is not recommended however that children spend time in the sun without protection due to the risk factors associated with long term sun exposure.
  • Dietary exposure – some children may have inadequate dietary intake of calcium and Vitamin D due to fussy eating, allergies or dietary limitations. It is also difficult to obtain enough Vitamin D from food alone as there are a limited number of foods with an adequate amount.
  • Skin pigmentation – naturally darker skin tones absorb less sunlight and therefore create less vitamin D than those with lighter skin tones.
  • Maternal deficiency and breastfeeding – inadequate levels of Vitamin D in the mother during pregnancy may have long term effects on the child’s bone and skeletal health. The most important factor for the development of Vitamin D deficiency in infants is the mother’s Vitamin D status. Unfortunately, breast milk is a poor source of Vitamin D and exclusively breast fed infants may be at risk of deficiency, particularly if they are dark skinned.
  • Recommendations to consider

    The National Health and Medical Research Council (NHMRC) released guidelines recommending an Adequate Daily Intake (ADI) of 200IU (5mcg) for children. The adequate intake is based on the amount of Vitamin D required for those who receive little sun exposure.2

    For the prevention and treatment of children at risk of Vitamin D deficiency, supplementation of 400IU (10mcg) may be required, or as directed by your healthcare professional. General supplementation guidelines are 200IU (5mcg) per day, or as directed by your healthcare practitioner.

    Supplements are available for children in chewable capsules and liquids for easier administration. Liquids can be administered straight in the mouth or to a favourite drink for those fussier eaters.

    If you believe that your child may be at risk of Vitamin D deficiency, a simple measurement of Vitamin D levels can be conducted by your healthcare practitioner.

    1. Braun L., Cohen M; Herbs & Natural Supplements: An evidence based guide, 3rd Edition; Elsevier; Australia; 2010
    2. National Health and Medical Research Council (NHMRC); Nutrient Reference Values for Australia and New Zealand including Recommended Dietary Intakes; Canberra; 2006