Lately, there has been some concern about whether using sunscreen might have a negative influence on children's mental development. At issue is whether blocking the UV rays from the sun interferes with vitamin D synthesis to the point that it may affect children's brainpower.

Because previous studies found an association between higher levels of vitamin D and improved cognitive function in adults, researchers in England set out to determine if this was also true in children, and what bearing different forms of the vitamin may have. Vitamin D3 is made in the body from exposure to sunlight. Vitamin D2 is derived from plant foods.

Researchers found higher levels of vitamin D3 were more common in children from affluent backgrounds. Children from disadvantaged backgrounds had higher levels of vitamin D2.

Just over 3,000 children in England had their levels of vitamin D2 and D3 measured at 9 years of age. Their performance in English, math, and science were assessed when they were between the ages of 13 and 14 and again between the ages of 15 and 16.

Researchers found higher levels of vitamin D3 were more common in children from affluent backgrounds. Children from disadvantaged backgrounds had higher levels of vitamin D2. The study results found that children with higher vitamin D3 levels did not have better academic achievement. Children with higher D2 levels showed worse academic performance; however, the researchers believe this could be a chance finding

The findings from this study are comparable to two other studies using data collected from the Third US National Health and Nutrition Examination Survey (NHANES III), which found no link between vitamin D levels and academic performance in children.

Perhaps the benefits of vitamin D on adults' cognitive function don't emerge until later in life. Perhaps the vitamin has more impact on the aging brain, or perhaps the effect is due to a cumulative lifelong effect of the vitamin. Whatever the reason, changes to public health guidance regarding protection against UV exposure have been suggested.

The study's authors say that protecting children from sunlight exposure protects against skin damage and skin cancer and is unlikely to have an harmful effect on academic performance.

The research was published online in the Journal of Epidemiology and Community Health.