Study Reveals Impact of Urbanization on Skin Microbiome in China

Research Overview

A recent research study conducted in China and published in the journal *Science Advances* explored the variations in skin microbiomes across different levels of urbanization. The findings indicate that individuals living in urban poverty exhibit less healthy skin microbes compared to their wealthier urban neighbors and rural counterparts.

The Importance of the Skin Microbiome

The skin, being the body’s largest organ, serves as a primary defense against diseases. It is populated by various microorganisms, including bacteria, fungi, and viruses, which are essential for maintaining host defense. Factors such as genetics and environmental conditions significantly influence the composition of the skin microbiome. Previous studies have shown that skin diseases are more common in urbanized areas and that the microbiome becomes notably disrupted in individuals with skin conditions.

Study Details

Researchers aimed to examine how an individual’s residential environment, specifically the level of urbanization, affects bacterial colonization. The study involved 231 women from five cities: the large cities of Kunming, Xi’an, and Hohhot, alongside the megacities of Beijing and Guangzhou. To ensure consistency, all participants were of the same ethnicity and aged between 25 and 35 years, having resided in their respective cities for at least five years. Skin microbiome samples were collected via cheek swabs in April 2015 and again in April 2016.

Findings on Urbanization and Skin Microbiome Composition

The findings revealed significant differences in bacterial colonization patterns between residents of megacities and non-megacities. The skin microbiomes of individuals in non-megacities displayed a broader diversity of species and a denser microbial network, suggesting greater resilience and support among microbes.

Additionally, the study highlighted socioeconomic influences on skin microbiome composition. Participants from higher socioeconomic backgrounds exhibited microbiomes more akin to those in non-megacities, indicating a less fragile state. Conversely, individuals in megacities had microbiomes that were more niche-based and susceptible to competition among bacterial species.

Role of Environmental Factors

The study’s results underscore the distinct variances in skin microbiome characteristics correlated with urbanization levels. The researchers suggested that pollution could be a contributing factor to these differences. Notably, the disparities in skin microbiomes may account for the higher prevalence of skin diseases in urbanized areas. This finding has led to a surge of interest in probiotic skin care products within the cosmetics industry.

Reference

Kim, HJ., Kim, H., Kim, JJ., Myeong, NR., Kim, T., Park, T., … Sul, W. J. (2018). Fragile skin microbiomes in megacities are assembled by a predominantly niche-based process, *Science Advances*, 4:3. doi:10.1126/sciadv.1701581