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Healthy Children

with Steven Parker, MD

This blog is now retired. Dr. P passed away on Monday, April 13, 2009. The WebMD Community will dearly miss his kind, caring, and often humorous manner.

Monday, October 13, 2008

Got Vitamin D?

Vitamin D is the new vitamin du jour. This week, the American Academy of Pediatrics Committee on Nutrition doubled its recommended intake of vitamin D from 200 to 400 IUs (international units)/day.

Why the change? I wrote about this 2 years ago (Vitamin D, Infants and Teenagers) and, as far as I can tell, it’s not because there have been any new important studies.

Rather, it has just gotten clearer that vitamin D is good stuff; that when taken in infancy and childhood it promotes strong bones lasting into adulthood; that it may play a role in preventing such nasty adult diseases as diabetes and cancer; that it may bolster the immune system; and that it can lower the rate of hip fractures in the elderly (yes, Lord willing, some day your little one will be an old coot). Not bad for a long ignored vitamin!


At the same time, low vitamin D levels have been documented in about 40% of infants, children, and teenagers. Why?

  • It’s well established that breast milk often doesn’t contain enough vitamin D to meet these requirements. This can be especially problematic in the dark winter months and with dark skinned infants (whose skin pigment repels the sunlight needed to make vitamin D in the body).
  • To ingest the new recommended amount of vitamin D, a child would have to drink about a quart of vitamin D-enriched milk a day (or, to reprise an old childhood nightmare, a teaspoon of cod liver oil). Lots of luck!
  • Most teenagers aren’t getting nearly enough vitamin D and there is reasonable evidence that adult bone hardness is related to vitamin D and calcium intake during the growth spurt of puberty.
  • People with darker skin or those who take their doctor’s advice and avoid direct sun exposure, also can’t make enough vitamin D (it’s estimated you need 10-15 minutes of direct exposure without sunscreen a few days per week to do so – much more if your skin is dark).

In fact, many argue that 400 IUs is still too low a dose for older kids. I think they are right: it really doesn’t make sense that the recommendation is 400 IUs / day for everybody, whether you are a 6 pound baby or a 160 pound teenager. My guess is that in a few years they will bump up the recommendations for bigger kids, so stay tuned.


FAQs: What to make of these new guidelines?

Should I give my child vitamin D supplements?
Consult your pediatric provider about this, but I vote yes to 400 IUs /day, unless it’s clear your child is getting enough through his/her diet and/or sun exposure (or unless s/he needs more due to a chronic disease or medication).

What if my infant is breast fed?
Then it’s all the more important to add a daily supplement of vitamin D to avoid the problems associated with inadequate intake and poor sunlight exposure.

What if my baby is formula fed?
In that case there is no need to supplement since all formulas sold in the United States contain extra vitamin D.

How will I know if my baby might have rickets?
Rickets – due to inadequate vitamin D over a long time – causes soft bones. Mostly it is seen in dark-skinned, breast-fed babies with little direct sun exposure who are not taking supplemental vitamins. Rickets is diagnosed by an X-ray, at which time there may be excessive bowing of the legs and/or swelling of the wrists and ankles.

Should I give more than the recommended 400 IUs?
Vitamin D is great stuff, but there is an important catch: Too much can be harmful. Unlike vitamin C which is just peed out if taken in excess, vitamin D is stored in our fat tissues. Too much can lead to an overdose and serious medical problems, so it’s important to strike the right balance. 400 IUs may still be too little in older kids and teenagers but, until we know more, I’d err on the side of too little, rather than too much.


Dr. P’s Bottom Line
I think vitamin D supplementation is a good idea for infants, children, and teenagers. 400 IUs extra/day appears safe and may have important short-term and long-term benefits for your child. I say, go for it!

Related Topics:

Posted by: Steven Parker MD at 12:41 pm


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