Skip to content

Sunlight affects the gut microbiota and vitamin D levels.

A worldwide rise in immune and inflammatory diseases such as multiple sclerosis and inflammatory bowel diseases has been linked to Western society-based changes in lifestyle and environment. These include decreased exposure to sunlight and the resultant impairment in the production of vitamin D, as well as dysbiotic changes in the makeup of the gut microbiome. However, it is still unclear if there are any direct links between sunlight/UVB light and the gut microbiome. Now, a study from researchers at the University of British Columbia shows how exposure to sunlight can change the human gut microbiome, specifically in people who are vitamin D-deficient. The team states their findings in healthy human participants could help to explain the protective effect of UVB against inflammatory diseases such as multiple sclerosis or inflammatory bowel disease. The opensource study is published in the journal Frontiers in Microbiology.

Previous studies show there are high rates of vitamin D deficiency in people who live in locations with long winter seasons, where the lack of UVB from sunlight means they don’t produce enough of the vitamin. Limited UVB exposure is one of the most important environmental factors linked to the onset of immune-mediated chronic inflammatory diseases such as multiple sclerosis and inflammatory bowel diseases. Vitamin D is also known to promote intestinal health, with vitamin D deficiency shown to promote dysbiosis of the gut microbiota, even in healthy individuals. However, it’s still unclear if there is a direct association between UVB light and human intestinal microbiota. The current study investigates whether exposing the skin to UVB light to increase vitamin D levels would also affect the makeup of the human intestinal microbiota.

The current study exposes the skin of 21 healthy female human volunteers to UVB light to see whether increasing vitamin D levels changes the makeup of intestinal microbiota. Nine of the participants took vitamin D supplements during the three months before the start of the trial, whilst the rest of the participants did not. Results show the majority of the participants who took supplements were vitamin D-sufficient at the start of the trial, whereas most of the group who did not take supplements were vitamin D-insufficient before the trial started.

Data findings show skin UVB ray exposure only significantly increases gut microbial diversity in the 12 subjects who were Vitamin D deficient at the start of the study. The lab states that prior to UVB exposure, these women had a less diverse and balanced gut microbiome than those taking regular vitamin D supplements. They go on to add UVB exposure boosted the vitamin D deficient participant’s microbiome to levels indistinguishable from the supplemented group whose microbiome was not significantly changed; microbiota species boosted in the study included Lachnospiracheae, Rikenellaceae, Desulfobacteraceae, and one group of Clostridiales.

The team surmises they have proven the effect on the microbiota composition after repeated UVB/sunlight exposure, specifically for subjects suffering from Vitamin D insufficiency. For the future, the researchers state proving the existence of this novel skin-gut axis could be used to promote intestinal homeostasis and health.

Source: News-Medical.Net

Get Healthinnovations delivered to your inbox:

Healthinnovations View All

Michelle Petersen is the founder of Healthinnovations, having worked in the health and science industry for over 21 years, which includes tenure within the NHS and Oxford University. Healthinnovations is a publication that has reported on, influenced, and researched current and future innovations in health for the past decade.

Michelle has been picked up as an expert writer for Informa publisher’s Clinical Trials community, as well as being listed as a blog source by the world’s leading medical journals, including the acclaimed Nature-Springer journal series.

Healthinnovations is currently indexed by the trusted Altmetric and PlumX metrics systems, respectively, as a blog source for published research globally. Healthinnovations is also featured in the world-renowned BioPortfolio,, the life science, pharmaceutical and healthcare portal.

Most recently the Texas A&M University covered The Top 10 Healthinnovations series on their site with distinguished Professor Stephen Maren calling the inclusion of himself and his team on the list a reflection of “the hard work and dedication of my students and trainees”.

Michelle Petersen’s copy was used in the highly successful marketing campaign for the mega-hit film ‘Jumanji: The Next Level, starring Jack Black, Karen Gilian, Kevin Hart and Dwayne ‘The Rock’ Johnson. Michelle Petersen’s copywriting was part of the film’s coverage by the Republic TV network. Republic TV is the most-watched English language TV channel in India since its inception in 2017.

An avid campaigner in the fight against child sex abuse and trafficking, Michelle is a passionate humanist striving for a better quality of life for all humans by helping to provide traction for new technologies and techniques within healthcare.

2 thoughts on “Sunlight affects the gut microbiota and vitamin D levels. Leave a comment

  1. This has been my philosophy all along that the gut microbiota powers the Immune System and Sunlight activates the conversion of Cholesterol into Vitamin D. Hence on the use of LLLT with some UV, my therapy units mimics the Nature’s way of enhancing the gut microbiota functions in supplying energy to the immune system. The healthy immune system determines the overall health of our bodies.

Leave a Reply

Translate »