Scientists at the University of Hawaiʻi at Mānoa found interesting correlations between gut health and mental health.
Samples were collected from more than 500 Native Hawaiians and Pacific Islanders with and without diabetes who participated in the Hawaiʻi Social Epigenomics of Early Diabetes Cohort.
The gastrointestinal tract is connected to the brain through bacteria that can regulate hormones and influence metabolism, which change brain activity.
Thousands of species of bacteria live in the gut and influence how the brain receives signals relating to appetite suppression that can ultimately affect the person's mood.
The UH team found that people with an abundance of Veillonellaceae bacteria in their gut had higher self-esteem. Individuals with low self-esteem showed abnormally low levels of this bacteria.
Eating leafy greens and fiber-rich foods can increase the production of bacteria that supports better mental health. It promotes higher levels of butyrate-producing bacteria. Butyrate is a fatty acid with anti-inflammatory effects and contributes to appetite suppression.
Pre-diabetic and diabetic cohorts in the study had low levels of butyrate-producing bacteria. It can be an early indicator of a potential diabetes diagnosis.
Diabetic cohorts also showed increased levels of Cyanobacteria. It's a bacteria that steals oxygen and nutrients from other organisms and can cause cancer in humans.
They also found Native Hawaiians and Pacific Islanders with diabetes or obesity had significantly higher microbial diversity — contrary to results from other ethnic groups.
"In other ethnic groups, it's been observed that there tends to be this increased microbial diversity in the gut in healthier people and depletion of that diversity in individuals with conditions such as diabetes and obesity. We found the opposite in our population," said Alika Maunakea, associate professor at the John A. Burns School of Medicine.
"We were struck by understanding what that might mean. One of the potential explanations could be diversity of our population, which really highlights the fact that biological findings from other race and ethnic groups might not necessarily be generalizable to the Native Hawaiian and Pacific Islander population," Maunakea explained.
