I've written more than a few stories on how Americans are by and large lacking in Vitamin D, but wow, was I unprepared for what I heard when I asked Frank Greer how many babies get enough Vitamin D: "If it's 30 percent, I'd be surprised."
Greer should know; he leads the American Academy of Pediatrics' committee on nutrition, which just doubled its recommendation for daily Vitamin D intake in children from 200 to 400 IU a day. The docs were concerned that many children, particularly young babies, aren't getting enough Vitamin D, which is essential for absorbing calcium from food and building bones. New evidence suggests that D also plays a vital role in the immune system, and might help protect against cancer and diabetes.
But how could so many American babies be missing out on this vital nutrient? Here's the deal: Many new mothers are Vitamin D deficient themselves, and can't deliver enough D to their babies while breastfeeding. Formula has enough Vitamin D to meet the pediatricians' goals. But moms who think they are doing the right thing nutritionally be breastfeeding need to give their babies supplemental vitamins, starting right after birth.
I always thought that parents were supposed to try to get vitamins into their kids by emphasizing healthy food, but that gambit doesn't work as well with Vitamin D. Oily fish contain D; hence the old-time winter remedy of cod liver oil. So does fortified milk. But a child would have to drink a liter of milk a day to get 400 IU—something that lots of kids, including my own, aren't about to do. Human skin synthesizes D, but people who live north of Chicago aren't exposed to enough sunshine from fall through spring to make their quota. People with darker skin, or those who cover themselves up to avoid sun exposure, also can't make enough D. Then there are the kids who spend almost all day either inside at school or inside watching TV. They could live on the Equator, and they still wouldn't get enough sun.
"There's no harm in giving a multivitamin," says Greer, who's a professor of pediatrics at the University of Wisconsin. In fact, he says, that's the only way that many children are going to get enough D. "All moms who are breastfeeding should be doing vitamin supplementation."
Here's Greer's advice, in summary:
• Give breastfed babies vitamin supplements that deliver 400 units of Vitamin D, starting shortly after birth.
• Older children and teenagers should get a multivitamin that includes 400 IU of Vitamin D; almost all do.
• Grandma was right; a teaspoon of cod liver oil contains 400 IU of Vitamin D.
• Encourage children to drink milk as a good source of bone-building calcium. But realize that unless a child drinks a liter of milk a day, she or he can't get enough Vitamin D in milk.
Greer is skeptical of the fad of claiming that Vitamin D is a miracle drug, capable of preventing cancer, multiple sclerosis, and diabetes. "Vitamin D has become the Vitamin E of the 21st century," he says, explaining that a decade ago E was touted as the miracle vitamin/cancer cure. It took a decade of research to figure out that not only was Vitamin E not a magic bullet, it actually increased the risk of lung cancer. "I don't think we're there" as far as being able to say that higher doses of D are safe, or effective. But for many children, Greer says, just getting up to 400 IU a day would be a big step forward.