Shining some light on Vitamin D and kids

At least once a week, a parent of one of my patients will ask me a question about Vitamin D.  And it's a good thing they ask.

In the Second National Report on Biochemical Indicators of Diet and Nutrition, released this month by the Centers for Disease Control and Prevention, Vitamin D levels remain a concern in some people – including kids.  The CDC reports that among children ages 1-11, close to 1 in 4 had levels that were considered "insufficient."

Why is D so important?  This vitamin plays a vital role in increasing the absorption of calcium and phosphorus, important for healthy bones and teeth in children.  New research published in the Archives of Pediatric and Adolescent Medicine finds that higher vitamin D levels helped decrease the incidence of stress fractures in adolescents. But vitamin D affects much more than just bones. Recent studies indicate that adequate D also aids the immune system, and decreases risk for chronic conditions like diabetes, high blood pressure and cancer.

To save you from banging down the door of your child's pediatrician to demand that his or her vitamin D level get checked, I asked Andrew Calabria, M.D., pediatric endocrinologist at the Children's Hospital of Philadelphia, for some tips on screening for Vitamin D deficiency.

Does every child need to have a Vitamin D level checked?

 I personally don't think every child needs a vitamin D level checked. I think it should be reserved for those at risk individuals.

Who is at highest risk for deficiency or insufficiency?

Dark-skinned children, children who are obese, and those with limited sun exposure may all require additional supplementation. Kids with medical conditions that cause chronic fat malabsorption like cystic fibrosis and those taking medications that may affect Vitamin D metabolism (seizure medications or long courses of steroids) also fall into this category. Exclusively breastfed infants require supplementation with 400 units of Vitamin D per day and are at risk if not supplemented.

What about the confusing information on the sun being the best source of vitamin D versus the risk of sun exposure?  What do you recommend?

This is a tough question. I think there must be a balance between protecting your skin and also receiving an adequate supply of vitamin D from what remains the principal source—the sun. I tell my patients it's okay to spend 15 minutes midday outside before applying sunscreen. And I definitely want children to spend much more time outside than 15 minutes!

So, that leaves the big question: How much D do kids need – and can they get it without taking a supplement? Follow these steps:

#1: Start with food – though that may not be enough. Calabria recommends that all children over 12 months should receive 600 to 1000 units per day of vitamin D (the Institute of Medicine recommends 600 units). D-rich foods and drinks will give them a good start toward that goal. Good dietary sources of vitamin D:

#2: Add at least 15 minutes of sunshine a day. (Follow the advice above for safe exposure!) Your skin produces D in the presence of the sun's ultraviolet rays.

#3. Discuss D supplements with your child's health care provider. Review his or her diet and outdoor time and ask which type and dose is best. One important note: Calabria discourages giving your child higher-than-recommended doses of supplementary D without consulting your health care provider first.

Beth Wallace, a registered dietitian at the Children's Hospital of Philadelphia, has more than six years of experience in providing nutrition care for children and adolescents.