Teens May Need a Vitamin D Boost

Healthnotes Newswire (July 3, 2008)—It’s well known that vitamin D is needed for proper bone growth in children and general bone health in children and adults, but it appears that adolescents worldwide are vitamin D deficient, and that current recommendations for daily D may not be enough for health and disease prevention. The good news: a recent study finds that giving teens higher amounts of vitamin D can raise them to healthy levels after one year of treatment.

The value of the “sunshine vitamin”

Vitamin D deficiency may lead to abnormal bone growth and development and to the development of chronic diseases in adulthood such as osteoporosis, cancer, and multiple sclerosis, and research suggests that the recommended daily intake of 200 IU of vitamin D may not be enough to prevent deficiency. The authors of this new long-term study suggest that a vitamin D blood level of 30 ng/ml (measured as 25-hydroxyvitamin D) is desirable based on expert recommendations, but many people have much lower levels. They tested a higher dose of vitamin D to see if it was safe for teens and effective in raising vitamin D levels.

In the study, 340 students, ages 10 to 17, were randomly assigned to take low-dose vitamin D3 (1,400 IU per week), high-dose vitamin D3 (14,000 IU per week), or placebo. After one year of treatment, adolescents who received the high-dose vitamin D had significantly higher blood levels (average, 38 ng/ml of 25-hydroxyvitamin D) compared with the levels in the low-dose vitamin D (17 ng/ml) and placebo groups (16 ng/ml).

The authors claim that vitamin D deficiency “is prevalent in children and adolescents worldwide.” They add that the high worldwide prevalence of vitamin D deficiency, the fact that many adult diseases begin in childhood because of vitamin deficiencies, and increasing evidence for the safety of higher doses of vitamin D should prompt a change in the current recommendations for an adequate daily amount. More research is needed to determine the safety of taking higher daily doses of vitamin D and to determine optimal levels for health and disease prevention.

Get your daily D

A person gets vitamin D several ways:

• Modest sun exposure (approximately 20 minutes per day)—people who get very little sun exposure, such as those who live in cloudy climates and at northern latitudes, may need to rely on diet and supplements to achieve adequate vitamin D levels

• Supplements such as vitamin D3 and cod liver oil—1 teaspoon of some brands provides 400 IU of natural vitamin D

• Some foods and beverages—fortified milk and cereal, fatty fish such as salmon and mackerel, and, to a lesser extent, eggs, beef, some cheeses, and other foods

According to the American Academy of Dermatology, most people get the current recommended amounts of vitamin D through incidental sun exposure. They recommend using sunscreen when outdoors in the sun and obtaining needed amounts of vitamin D through foods and supplementation. However, for those not likely to take supplements or deliberately get enough D in the diet, it is important to weigh the risks and benefits of sun exposure against your risks for bone disease and other health issues. Talk to your doctor about your vitamin D needs and what combination of sources might be best for you.

(J Clin Endocrin Metab 2008:doi:10.1210/jc.2007-2530)