A long-term U.S. study, published online in the journal Gut, reveals that living in geographic locations with plenty of sunshine may ward off inflammatory bowel disease, especially in those over 30.
The research findings may eventually pave the way for new treatments and preventive measures for the disease, which includes Crohn’s disease and ulcerative colitis.
Study authors based their research on data culled from the Nurses’ Health Study in 1976 and the second subsequent study starting in 1989.
Participants place of birth and residence between ages 15 and 30 was documented from both studies along with any diagnosis of IBD recorded up to 2003.
The study revealed that women living in southern climates were 52 percent less likely to develop Crohn’s disease by age 20 and 38 percent less likely to get ulcerative colitis.
“A leading explanation for this north-south gradient in the risk of ulcerative colitis and Crohn’s disease may be differences in exposure to sunlight or UVB radiation, which is generally greater in southern latitudes,” the authors said.

“UV radiation is the greatest environmental determinant of plasma vitamin D, and there is substantial experimental data supporting a role for vitamin D in the innate immunity and regulation of inflammatory response.”