This study found that shining near infrared light on the digestive system had a significant positive effect on the health and diversity of the microbiome in mice.  The study found, “There was a significant (p < 0.05) difference in microbial diversity between PBM- and sham-treated mice. One genus of bacterium (Allobaculum) significantly increased (p < 0.001) after infrared (but not red light) PBM by day 14. Despite being a preliminary trial with small experimental numbers, we have demonstrated for the first time that PBM can alter microbiome diversity in healthy mice and increase numbers of Allobaculum, a bacterium associated with a healthy microbiome. This change is most probably a result of PBMt affecting the host, which in turn influenced the microbiome. If this is confirmed in humans, the possibility exists for PBMt to be used as an adjunct therapy in treatment of obesity and other lifestyle-related disorders, as well as cardiovascular and neurodegenerative diseases. The clinical implications of altering the microbiome using PBM warrants further investigation.”

Since the “human microbiome is intimately associated with human health, with a role in obesity, metabolic diseases such as type 2 diabetes, and divergent diseases such as cardiovascular and neurodegenerative diseases.”  This is another great reason to explore shining with light.

https://www.ncbi.nlm.nih.gov/pubmed/30074108