Catch Some Rays to Boost Gut Health

Fresh evidence is emerging of a skin-gut axis that links type B ultraviolet (UVB) exposure to the microbiome, a finding that has implications for those suffering from autoimmune and inflammatory diseases. University of British Columbia researchers divided 21 healthy young women into two groups: nine took vitamin D supplements during Vancouver’s long, dark winter, and 12 didn’t. After three months, only the non-supplement-takers tested as being deficient in vitamin D. Both groups were exposed to three, one-minute, full-body UVB light sessions; within a week, vitamin D levels increased 10 percent on average and the gut microbiota diversity of the low-D group rose to match that of the sufficient-D group. Along with other probiotic bacteria, there were increases in Lachnospiraceae species, typically low in the guts of people with inflammatory diseases, increased with the UVB exposure.