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Kids' Bones at Risk From Low Vitamin D

Hours of playing video games and drinking sodas instead of
milk may be putting children's bones at risk from low vitamin D levels.

A new study shows more than half of otherwise healthy children have low
vitamin D levels in their blood, which may put them at risk for bone diseases,
like rickets.

Vitamin D-fortified milk is the main source of vitamin D in the diet, but
the vitamin is also produced within the body as a result of sunlight

That's why researchers say those low vitamin D levels may reflect current
trends of children spending less time outdoors and drinking less milk than in
the past.

Severely low levels of vitamin D can lead to muscle weakness, bone weakness,
and rickets. Earlier studies -- cited by the researchers -- show that vitamin D
also plays an important role in immune system function.

Vitamin D and Kids

In the study, published in the American Journal of Clinical
, researchers analyzed blood levels of vitamin D in 382 healthy
children from ages 6 to 21.

They found 55% of the children had lower than recommended vitamin D

African-American children, children over age 9, and those who didn't get
much vitamin D in their diet were the most likely to have low levels of the
vitamin in their blood.

Vitamin D levels also dropped during winter. Overall, 68% of children had
inadequate stores of the vitamin in their blood during the colder months when
they spent more time indoors.

"Vitamin D deficiency remains an under-recognized problem overall, and
is not well studied in children," says researcher Babette Zemel, PhD, a
nutritional anthropologist at Children's Hospital of Philadelphia, in a news

Zemel says more study is needed to determine appropriate blood levels of
vitamin D in children, and a review of current recommendations for vitamin D
intake may be needed.

By Jennifer Warner
Reviewed by Louise Chang
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