Lower oral microbiome diversity linked to higher depression symptoms

A rich and varied mix of microbes in the mouth, in particular bacteria, is not only important for our oral health, but may contain instructions for other disorders. A new study led by researchers from NYU Rory Meyers College of Nursing shows that a lower diversity of microbes in the mouth is associated with depression.

The mouth is the home base between 500 billion and 1 trillion bacteria-de on the second largest community of microorganisms in our body, after the intestine. A growing number of studies points to the connection between the oral microbiome and our overall health, from diabetes to dementia, a relationship that is thought to be driven by inflammation and disruptions for the immune system.

A recent study in mice found a potential link between depression and the diversity of bacteria in the gut, but there is less known about the relationship between the oral microbiome and depression.

“Having a better understanding of the relationship between the oral microbiome and depression can not only help us learn about the mechanisms that underlie depression, but can contribute to the development of new biomarkers or treatments for mood disorders,” said Bei Wu, Vice -Decan for research at Nyu Rory in the Study in the Study, in the Study in the Study in the Study, in the Study in the Study, in the Study in the Study, in the Study, in the Study, in the Study, in the Study, in the Study, in the Study, in the Study, in the Study, in the Study of Nursior, in the Study or NURSIORSing, in the Study or Nursior, in the Nursior, and the Senior. Journal BMC Oral Health.

In order to investigate the connection between the oral microbiome and depression, the researchers investigated survey and biological data of the National Health and Nutrition Examination Survey (NHANES), carried out by the Centers for Disease Control and Prevention. The use of data from more than 15,000 American adults aged 18 and older collected between 2009 and 2012 compared the researchers that measure the symptoms of depression with saliva samples. Gensequencing was used to identify the microbes in the saliva and to measure the diversity of the oral microbiome.

The researchers discovered that people with less diversity in their oral microbiomas were more likely to have symptoms of depression. Additional analyzes showed that smoking, drinking and dental care can all change the composition of bacteria in the mouth, can influence the relationship between the oral microbiome and depression.

These findings suggest that, with more research, the oral microbiome can be used to diagnose or treat depression. Based on this study, however, it is not clear whether the diversity of microbes in the oral depression influences or whether depression leads to changes in the oral microbiome or if there is a bidirectional relationship between the two.

It is possible that the oral microbiome influences depressive symptoms due to inflammation or changes in the immune system. Conversely, depression can cause changes, including the intake of diet, poor oral hygiene, more smoking and drinking, or the use of medicines of which can all change oral microbiome. We need more research to understand the direction and underlying paths of this relationship. “

Bei wu, vice -dean for research at the NYU Rory Meyers College of Nursing

“This work is part of a broader effort to understand how oral microbiome not only influences mental health, but also cognitive decline and the beginning of dementia,” she added.

Additional study authors are Xichenhui Qiu, Ting Xu, Yiqing Huang, Changning Wei and Lina Wang.