“A U.S. study found a link between oral microbiome diversity and depression, with lower alpha diversity linked to higher depression risk and significant differences in beta diversity between depression-infected and non-depressed individuals, indicating potential role of oral microbiota.”
Depression was recognized as a global mental health concern, especially among adolescents and young adults. While the gut microbiota had been widely studied in depression, the role of the oral microbiome remained less understood. Emerging evidence suggests the oral microbiome could influence systemic and brain health through the oral-brain axis.
A study published in the Journal of Affective Disorders examined the link between oral microbiome diversity and depression using data from 6,212 participants in the National Health and Nutrition Examination Survey (NHANES) 2009–2012. The study reported that 10.03% of participants had been diagnosed with depression.
Results showed that higher alpha diversity in the oral microbiome was negatively associated with depression. Specifically, measures such as observed amplicon sequence variants (ASVs) and Faith’s phylogenetic diversity were inversely correlated with depressive symptoms. Linear regression analysis indicated that greater alpha diversity was linked to lower PHQ-9 scores, suggesting fewer symptoms of depression. Additionally, beta diversity analysis revealed significant differences in microbiome composition between individuals with and without depression.
The findings emphasized the significance of the oral-brain axis and pointed to the need for further studies to understand the underlying mechanisms and investigate potential therapeutic strategies involving the oral microbiome.
(Source:https://www.sciencedirect.com/science/article/abs/pii/S0165032725003568)