Increased Sun Exposure Decreased Folate Levels In Women of Childbearing Age Interview with
Michael Kimlin Professor of Cancer Prevention Research Institute of Health and Biomedical Innovation Queensland University of Technology AustraliaMichael Kimlin
Professor of Cancer Prevention Research
Institute of Health and Biomedical Innovation
Queensland University of Technology
Australia What are the main findings of the study?

Answer: The main findings of this study were that women who where classified as having the highest level of sun exposure in our sample had a significantly larger drop in blood folate levels compared to women with lower sun exposures. This was quite a powerful finding, as all women were supplemented with folate and tested so that so that we knew that each sun exposure group had similar average levels of blood folate at the start of the study. We then measured their sun exposure over a week and took a sample of blood at the end of this week to see how the degree of sun exposure affected folate levels. Were any of the findings unexpected?

Answer: We knew from previous research that ultraviolet radiation degrades folate in blood, but this was for blood contained in test tubes in a laboratory. There has also been some previous research  conducted in Japan and Norway looking at this association and reporting that folate in humans can be affected by sun exposure, but these were not conducted in an environment were there was high natural solar radiation or in childbearing age women, where folate is particularly important for reducing risk of neural tube defects such as Spina Bifida. So while we thought there may be a definite association, we were surprised at the strength of this association between sun exposure and blood folate degradation. What should clinicians and patients take away from your report?

Answer: This research reinforces the importance of sun protection public health messages that have long been used for reducing the risk of skin cancer, especially in high sun exposure environments such as Australia. Protecting yourself from the sun during peak periods (9am to 3pm) for instance, is  is recommended to the general population in Australia and in many other countries. It is important that pregnant women minimise sun exposures at these times  to reduce risk of skin cancer and possibly folate degradation.

An important point I also want to make is that Vitamin D is also essential to health and we get most of this from sun exposure- this has caused some confusion among many people into how much sun exposure that you need. Researchers continue to enhance the evidence base that will let us improve health messages for balancing sun protection and ensuring adequate vitamin D. However, as many factors such as geography, skin colour and season can effect the adequacy of vitamin D produced in the skin from sun exposure, it is best if women talk to their doctor about how to ensure that they have adequate vitamin D, while reducing the risks of excessive solar ultraviolet radiation exposure. What recommendations do you have for future research as a result of this study?

Answer: This is preliminary research in this population and we are planning much larger population studies that will assess the association between sun exposure and folate degradation in childbearing age women and seeing how this differs by season and geographical region. To confirm a casual link, a controlled trial will also be needed.


Exposure to solar ultraviolet radiation is associated with a decreased folate status in women of childbearing age.  D. Borradalea, E. Isenringb, E. Hackera, M.G. Kimlina

Journal of Photochemistry and Photobiology B: Biology

Volume 131, 5 February 2014, Pages 90–95



Last Updated on December 21, 2014 by Marie Benz MD FAAD