Did you know that our microbiomes—the population of microbes living in and on each of us—are mostly formed by age 3? Before the Museum’s upcoming exhibition The Secret World Inside You opens November 7, we’re offering weekly primers on the microbiome and the research surrounding it from Curators Rob DeSalle and Susan Perkins, as well as from other scientists who are working in this exciting field.

Our latest post comes from Dr. Maria Gloria Dominguez-Bello, an associate professor in the Department of Medicine at New York University. Dr. Dominguez-Bello’s lab explores how the human microbiome takes shape and the impact modern lifestyles have on its development.

Dr. Maria Gloria Dominguez-Bello

© G. Dominguez-Bello

What’s Behind the Modern Microbiome?

Our lab at NYU is focused on determining how babies develop their microbiome from birth, and how the practices of everyday life impact the population of beneficial microbes in our bodies. Recent work in the field suggests a relationship between a modern Western lifestyle and low intestinal microbiome diversity. This lack of diversity could account for increased risks of diseases including asthma, type 1 diabetes, and obesity.

To study this fascinating subject, we are conducting several studies. Most basically, we’re following babies born by caesarean section and those delivered vaginally. We swab different parts of the babies’ bodies, including skin and mouth, and sample their feces to study how they develop the complex microbiome that they have by the age of 3, which resembles that found in adults.

Since caesarean section babies don’t acquire the acidic vaginal microbiome of their mothers during birth and instead acquire skin bacteria first, we are also exposing infants born by caesarean section to the vaginal microbiome of their mothers, and determining how much of this microbiome we can restore after the fact.

Babies receive their first microbiomes from their mothers.

© AMNH/B. Pedersen

In a second phase, we plan to study if the restoration or vaginal “seeding” protects infants from increased risks that may be associated with caesarean-section birthing, such as asthma, obesity, and allergies. Experiments in mice also help us to understand the physiological effects of different microbial cocktails.

Other projects in our lab explore how modern-life practices influence our microbiomes and the microbe populations found in our homes.

We know that our Westernized culture is very anti-microbial—not surprisingly, considering our history of terrible epidemics and lethal infections. However, it seems that now that we’ve controlled for infectious diseases, thanks to antibiotics and vaccines, diseases related to abnormal immune and metabolic responses are on the rise.

A diverse population of microbes, like the Bifidobactruium illustrated here, is key to good health.

© AMNH/B. Pedersen

That’s why we are studying healthy individuals who live traditional lifestyles to learn more about their physiology, their microbes, and their homes’ microbes. This effort to understand a more traditional microbiome could help us understand why are we losing microbiome diversity, how we are changing environmental microbes in our built environment, and what the consequences of those changes may be.