A recent Australian study explored a connection between sun exposure and risk of inflammatory bowel disease in children.
Inflammatory bowel disease (IBD) is a chronic intestinal condition that includes two main forms, namely ulcerative colitis and Crohn’s disease. The disease is uncommon in children, but research estimates that 15-25% of diagnoses occur in people under the age of 20 years. Despite the efforts of science, we still do not know much about what causes IBD. Although the exact causes of IBD are unknown, environmental factors, together with genetic, microbial, and immunological factors, play a role in the risk of disease. Previous research suggested a link between inflammatory bowel disease in children and exposure to UV radiation. Building on these previous findings, researchers from The Australian National University (ANU) set out to study the association between sun exposure and IBD further. Their results are published in the Journal of Pediatric Gastroenterology and Nutrition.
The new study evaluated sun exposure in relation to the risk of developing IBD
The scientists recruited a group of children between the age of 0 and 17 years diagnosed with IBD, and another group of children of the same age but with no prior IBD diagnosis. Both groups of participants were recruited from two hospitals in Melbourne, Australia. The parents (or guardians) of the children then completed a series of questionnaires. The questionnaires asked questions related to sun exposure habits and other factors such as physical activity, education, and parental smoking. These data allowed the researchers to perform a statistical analysis and evaluate the role of sunlight exposure in the risk of IBD.
Sun exposure reduced the risk of IBD in children
This approach led the team of researchers to find a clear association between sunlight exposure and IBD. They found that every additional 10 minutes of exposure to the sun during holidays or weekends reduced the risk of developing IBD by 6%. While the study reports that sun exposure may be beneficial in reducing the risk of IBD in children, the analyses were completed based on the parent’s recollection of sun exposure. Further research will be needed to confirm this association.
These results support the theory of a protective effect of sun exposure against IBD, but further research is required to unravel the mechanisms that lead to this outcome. If future studies will confirm these findings, sun exposure may become a tool for the prevention of IBD. While potentially beneficial, such an approach will need to take into account the risks that come with sun exposure, such as skin cancers.
Written by Raffaele Camasta, PhD
Holmes, E. A., Ponsonby, A.-L., Pezic, A., Ellis, J. A., Kirkwood, C. D., & Lucas, R. M. (2019). Higher Sun Exposure is Associated With Lower Risk of Pediatric Inflammatory Bowel Disease. Journal of Pediatric Gastroenterology and Nutrition.
Mulder, D. J., Noble, A. J., Justinich, C. J., & Duffin, J. M. (2014). A tale of two diseases: The history of inflammatory bowel disease. Journal of Crohn’s and Colitis. 8(5), 341-348.
Zhang, Y.-Z., & Li, Y.-Y. (2014). Inflammatory bowel disease: Pathogenesis. World Journal of Gastroenterology. 20(1), 91-99.
Sunshine may decrease risk of inflammatory bowel disease. https://www.eurekalert.org/pub_releases/2019-05/anu-smd052919.php