# Pilot study assessing gut microbial diversity among sexual and gender minority young adults

## TL;DR

This study found that sexual and gender minority young adults have less gut microbial diversity, which may contribute to their higher health risks.

## Contribution

The study is among the first to explore gut microbiome differences in sexual and gender minority young adults.

## Key findings

- SGM individuals showed significantly lower gut microbiome alpha diversity compared to cisgender-heterosexuals.
- SGM group had higher Bacteroidetes and lower Firmicutes, Actinobacteria, and Proteobacteria phyla abundance.
- These differences remained even after adjusting for mental health outcomes.

## Abstract

Evidence supports that people identifying as a sexual or gender minority (SGMs) experience minority-related stress resulting from discrimination or expectations of prejudice, and that this is associated with increased mental and physical health problems compared to cisgender heterosexuals. However, the biological mechanisms driving minority-related stress impacts remain unknown, including the role of the gut microbiome. Thus, the aim of this study was to determine the relationship between SGM status and gut microbiome health among young adults attending a 4-year university. To this end, a prospective pilot study was completed in the fall and spring semesters of 2021–22. Self-identified SGMs (N = 22) and cisgender-heterosexuals (CIS-HET, N = 43) completed in-person interviews to provide mental health data and demographic information. Nail and saliva samples were collected at the time of interview to quantify chronic and acute cortisol. Stool samples were collected within 48 hours of interview for microbiome analysis. Assessment of the gut microbiota identified a significant reduction in alpha diversity among the SGM group, even when adjusting for mental health outcome. SGM group showed trends for higher abundance of microbes in phylum Bacteroidetes and lower abundance of microbes in phyla Firmicutes, Actinobacteria, and Proteobacteria compared to the CIS-HET group. These findings support that the gut microbiome could be contributing to negative health effects among the SGM community.