Study: Lifestyle, demographic factors account for some of the variations in skin, oral microbiomes

In a study published earlier this month in the journal mBio​, scientists from Amway and Microbiome Insights, which is associated with the University of British Columbia, delved into the factors that affect the diversity of oral and skin microbiomes. Titled “New Insights into the Intrinsic and Extrinsic Factors That Shape the Human Skin Microbiome,” ​​​the  study aimed to find out what demographic, physiologic and lifestyle factors shape the oral and skin microbiomes.

Data from thousands of swabs analyzed

The epidemiological study enrolled 495 subjects who ranged in age from 9 to 78. The researchers  collected more than 2,500 swab samples from four skin sites and from the mouths of the subjects.

“While this study was a tremendous challenge to design, execute, and analyze, it takes studies with a large base like this to tease out the important factors that impact the skin microbiome and its critical role in skin health and beauty,”​ said Greg Hillebrand, PhD, Senior Principal Research Scientist at Amway, who led the study.

The researchers used 16S rRNA gene amplicon sequencing to analyze the samples.  They also collected physiological data from the hosts through standardized questionnaires and noninvasive biophysical methods.

“Using a combination of statistical modeling tools, we found that demographic, lifestyle, and physiological factors collectively explained 12 to 20% of the variability in microbiome composition. The influence of health factors was strongest on the oral microbiome,”​ they wrote.

Linking one organism to skin aging

One of the goals of the study was to try to understand how the microbiome of aging skin differs from that of younger subjects.  In this case, the organism Corynebacterium kroppenstedtii​ seems to be particularly relevant.  The relationship of this organism to skin aging parameters had been discovered earlier by Amway research and is the subject of a patent application, the company has said.

“What drives the dominance of ​C. kroppenstedtii after middle age? One possibility is that ​C. kroppenstedtii specifically metabolizes fatty acids typically found on skin at old age. Although considered a skin commensal, there is evidence that this species can act as an opportunistic pathogen,” ​the authors wrote. 

But the authors stressed that their study is just a first look at the many factors affecting the makeup of the skin and oral microbiomes, and what these differences might mean.  How might diet, for example, affect this picture?

“While skin aging is partly dictated by lifestyle, the lifestyle factors we measured did not affect taxa associated with skin aging, suggesting that certain species are selected by the host independently of external perturbations. Further studies that collect relevant lifestyle data (for example, a detailed record of skin care practices and diet) are needed to determine whether certain host habits affect skin aging directly or via the involvement of microbial components. With this information, we will be able to assess whether skin aging can be modulated by manipulating the microbiome,”​ they wrote.

Source:​ mBio​
Published online 2019 Jul 2. doi: 10.1128/mBio.00839-19
New Insights into the Intrinsic and Extrinsic Factors That Shape the Human Skin Microbiome​​​
Authors: Dimitriu PA, Iker B, Malik K, Leung H, Mohn MW, Hillebrand  GG