Most kids in U.S. have low levels of vitamin D

Aug 3, 2009 6:07 PM

Seven out of 10 U.S. children are reported to have low levels of vitamin D, according to a study of more than 6,000 children published online today by the journal Pediatrics. Recent studies have looked at the growing problem of vitamin D deficiency in adults. These findings suggest that millions of children may also be missing out on the "sunshine vitamin" and could very well be at increased risk for weak bones, certain cancers, and a host of other illnesses.

Researchers looked at data on more than 6,000 children, ages 1 to 21, collected by the National Health and Nutrition Examination Survey from 2001 to 2004. The researchers found that 9 percent of the study sample, equivalent to 7.6 million children across the U.S., was vitamin D deficient (defined as less than 15ng/mL of blood), while another 61 percent, or an estimated 50.8 million, was vitamin D "insufficient" or rather had a blood level of vitamin D that, while not deficient, was less than optimal (15 to 28 ng/mL of blood).

Low vitamin D levels were especially common in children who were older, female, African-American, Mexican-American, obese, or who drank milk less than once a week. Researchers also found that children’s sedentary lifestyles put them at risk for vitamin D deficiency. Children who spent more than four hours a day watching TV, playing video games, or using computers had low levels of the vitamin.

In November 2008, the American Academy of Pediatrics published its updated vitamin D guidelines, recommending that infants, children, and teens have a minimum intake of 400 international unitsper day. The previous recommendation, issued in 2003, called for 200 IUs per day, beginning in the first two months of life.

In light of a multitude of studies that have been published over the last several years, the Institute of Medicine’s Food and Nutrition Board this week is having an "information gathering" meeting to address the increasing evidence regarding vitamin D and health.

As researchers continue to evaluate and discuss the increasing evidence linking low levels of vitamin D to a variety of health issues, here are some immediate ways to help make sure your child gets enough vitamin D:

Drink milk. Milk, formula, and fortified soy milk are the biggest sources of vitamin D in most kids' diets, so make sure that your child drinks enough. If you're breast-feeding, talk to your doctor about supplements for your infant.

Get it from food. Take a look at the list of foods high in vitamin D, including orange juice, salmon, and eggs.

Turn off the TV and computer and encourage exercise and healthy eating habits. Excess body fat traps vitamin D, leading to lower levels of it in the blood.

Children who are consuming less than one quart per day of vitamin D-fortified formula or milk, or with an increased risk of vitamin D deficiency, such as those taking certain medications, may need higher doses of vitamin D. If you are concerned that your child may not be getting enough vitamin D, be sure to talk to your pediatrician about a supplement.

A word on sunscreen

Research suggests that the widespread use of sunscreen may be a factor in the rise of vitamin D deficiency. Sunscreen blocks out rays that help the skin make this vitamin, even though wearing sunscreen is important to protect against skin cancer. While experts say as little as 10 minutes in the sun without sunscreen three or four times a week provides the vitamin D most people need and is likely to be safe, this continues to be an area of some controversy. The American Academy of Pediatrics currently recommends that infants and young children not be in direct sunlight when they are outside, particularly infants younger than 6 months of age. And sunscreen should be used on all children when in sunlight.

—Ginger Skinner

See our tips on staying safe in the sun, and before you buy sunscreen, see our new Ratings (subscribers only).