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Children Not Getting Enough Vitamin D, Study Concludes

August 3, 2009 at 12:00 AM EDT
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More than 60 percent of children have "insufficient" levels of Vitamin D, a study published by the journal Pediatrics concluded on Monday. Gwen Ifill reports.

GWEN IFILL: Finally tonight, new concerns about whether children are getting enough Vitamin D. Two studies in the journal Pediatrics found that 70 percent of those under the age of 21 fall short and linked low levels of Vitamin D to high blood pressure, low blood sugar, and other complications.

Dr. Michal Melamed of the Albert Einstein College of Medicine is the lead author for one of the studies, and she joins us now.

Welcome, Dr. Melamed.

DR. MICHAL MELAMED, Albert Einstein College of Medicine: Thank you. Good evening.

GWEN IFILL: So, tell us, what is the value of Vitamin D?

DR. MICHAL MELAMED: So, Vitamin D — it’s important to know that Vitamin D is actually not a vitamin. It’s a hormone. And so it actually plays a very important role in the body.

Vitamin D is known classically for making strong bones, so people who have Vitamin D deficiency — and kind of the ultimate Vitamin D deficiency is rickets — have very weak bones, and that can lead to deformity. The kids with rickets have bowed legs, and that can lead to easy fractures.

GWEN IFILL: Rickets is a very — pardon me — Rickets is a very old-fashioned disease. We haven’t heard of that in years. Why now are we hearing about Vitamin D deficiency? And how is it manifesting itself?

DR. MICHAL MELAMED: So, it’s very interesting. The reason why we did this study was because there’s actually been many case reports recently in the medical literature showing that there are some kids in the United States that are developing rickets, which, like you said, we thought had gone away.

We think that there are several things that have been causing this resurgence of rickets. The big things are that I think kids are probably drinking less milk, kids are spending less time outdoors, and the time outdoors that they’re spending, they have sunscreen on, and so they don’t get the UVB radiation that you need to make Vitamin D, and kids are not actually taking as many supplements as they did years ago.

Not enough time outside

GWEN IFILL: You make an interesting point. Vitamin D was known as the sunshine vitamin. Why isn't it just found in sunshine? How could there be a deficiency if you're getting outdoors?

DR. MICHAL MELAMED: So we actually -- one of the things that we looked at in our study were kids who spent more than four hours a day either watching TV or playing on their computer or watching or playing video games. And actually about 25 percent of the kids in the study spent more than four hours a day.

And so if you think they go to school for eight hours and then spend four hours a day watching TV, there's really not that much time to go outdoors.

GWEN IFILL: OK, so there is a dilemma here, which is that we say that children have to be covered in sunscreen. We all have to be covered in sunscreen before we go outdoors, and now you're telling us, however, we're not getting enough sun. How do you balance that out?

DR. MICHAL MELAMED: Right. So, the recommendations for sunscreen are very good recommendations, but 10 to 15 minutes a day is really all a person needs in order to make enough Vitamin D to last for the next 24 hours, and that's more so in light-skinned people. Darker-skinned people need a little more time in the sun.

So one, you know, easy thing to do is to -- when you go with your kids out to the store, you don't necessarily need to put the sunscreen on them if they're only going to be outside for 10 to 15 to 20 minutes. But if they're going to go to the beach, you know, for two to three hours of direct sunlight, that may be the time to put the sunscreen on.

Deficiency causes complications

GWEN IFILL: So what happens if adults or children don't take these supplements or for some reason remain deficient? Are there other diseases which can arise from this?

DR. MICHAL MELAMED: Yes. So, the diseases that have been linked to low Vitamin D levels are actually many. Low Vitamin D levels have been linked to diabetes, to high blood pressure, to all different types of cancer, including colon cancer, and breast cancer, and to cardiovascular disease.

So most of these studies were done in adults. And our two studies that came out today actually looked at it in kids in adolescence. And what the two studies showed was that the kids with the low Vitamin D levels actually had higher blood pressures, higher blood sugars, which, you know, is a precursor to diabetes, and had lower HDL cholesterol levels, which is the good cholesterol.

GWEN IFILL: Is there...

DR. MICHAL MELAMED: And all of these...

GWEN IFILL: I'm sorry. Pardon me. Is there a diet -- is there a solution to be found in diet?

DR. MICHAL MELAMED: So it's actually very hard to get enough Vitamin D from diet. The natural sources of Vitamin D in diet are fatty fish. And as we probably know, a lot of kids don't like to eat sardines.

Milk is fortified with Vitamin D, but to get the current 400 international units that's recommended by the American Academy of Pediatrics, a child would actually have to drink a quart of milk every day, which, you know, is a lot for kids. And then there are other sources in the diet, but they don't provide very much.

GWEN IFILL: Well, I'm with them on the sardines. Dr. Michal Melamed, thank you so much.