Imbalances in Gut Bacteria Linked to Low Self-Esteem

A growing body of research connects gut health to mental well-being. The ecosystem within our digestive tract, also known as the gut microbiome, is home to many species of tiny organisms, such as bacteria, fungi, and viruses. When the ecosystem is balanced, these organisms help keep the body functioning. But when an infection or stress disrupts the microbiome, the imbalance can affect not only our gut, but our entire body, and possibly even our mental health.

Compared to other racial and ethnic groups in Hawaii, Native Hawaiian and Pacific Islander (NHPI) people are disproportionately affected by mental health conditions and are at higher risk for many other chronic diseases—including those related to the gut and immune system, such as diabetes and obesity. Self-esteem is a key indicator of mental well-being. Prior research has found a connection between low self-esteem (LSE), mental health conditions, the gut microbiome, and the immune system. Scientists believe that an imbalance in the gut can cause inflammation, which in turn can affect mental health. But few studies have examined a possible link between self-esteem, the gut microbiome, and mental well-being among NHPI people.

Researchers recruited 68 participants living in Oahu, most of whom were NHPI individuals. The participants gave blood and stool samples and filled out a previously validated survey about their mental health, particularly their self-esteem. The survey has been shown in previous studies to be reliable in many different ethnic groups. The study team also collected basic health information: height, weight, blood pressure, heart rate, and blood sugar level. The researchers used the blood and stool samples to look at the health of participants’ immune systems, their blood sugar levels, and the species living in their microbiomes. Based on survey responses, they divided participants into two groups: those with normal self-esteem (NSE), and those with LSE.

Analysis of the data showed that participants with LSE had a lower concentration of the hormone that helps immune function compared to participants with NSE. Among those with LSE, the researchers also found an association between inflammation and the abundance of certain species of gut bacteria that may be related to LSE. This association remained even after the researchers accounted for weight, sex, and age. The evidence supports the idea that gut health and mental well-being may be connected in NHPI people, as with other groups, which suggests that treatments targeting the microbiome might help support their mental health.

The researchers noted that the study’s sample size was small, and that surveys may not be the most accurate measure of a person’s mental state. They also noted that it is not clear from these results whether a microbiome imbalance is the cause of LSE or a result of it. It is also possible that both conditions are triggered by some other factor.

The researchers suggested that more studies are needed to examine whether these findings can be generalized to other aspects of mental health, and to continue to explore the link between gut bacteria, the immune system, and mental well-being.

Citation
Becerra, C. Y., Wells, R., Kunihiro, B. P., Lee, R. H., Umeda, L., Allan, N., Rubas, N., McCracken, T. A., Chandler, Lee M.-H., Gerard, F., Phankitnirondorn, K., Dye, C. K, Yamamoto, B. Y., Peres, R., Juarez, R., & Maunakea, A. K. (2023). Examining the immunoepigenetic-gut microbiome axis in the context of self-esteem among Native Hawaiians and other Pacific Islanders. Frontiers in Genetics, 14. https://doi.org/10.3389/fgene.2023.1125217

Page updated Sept. 17, 2024  |  published Aug. 30, 2024