The two main sources of vitamin D are sun exposure and oral intake. Compared to those with two hours or less of daily screen time, children and adolescents who spend five or more hours daily watching television or videos face more than double the risk of vitamin D deficiency, according to a research letter published in Pediatric Research.
The Vanderbilt University Medical Center study, from resident physician Rishub Das, MD, and Eman Bahrani, MD, assistant professor of Dermatology, analyzed data from more than 2,700 U.S. children ages 2-17 years. The researchers found that average vitamin D levels decreased as screen time increased, with the lowest levels seen in children watching five or more hours of TV daily.
The association was particularly strong among adolescents, Black children, and those reporting less physical activity. About 15% of children in the study had vitamin D deficiency, defined as blood levels below 50 nanomoles per liter.
The findings suggest that excessive recreational screen time may reduce outdoor activities and sunlight exposure, potentially contributing to vitamin D deficiency. This deficiency can affect bone health and is linked to conditions like psoriasis, eczema and depression.
The researchers recommend that health care providers screen pediatric patients for electronic device use to identify those who might need vitamin D supplementation or increased outdoor activity with proper sun protection.
