Related Experiment Video

Updated: Mar 31, 2026

Probiotic Studies in Neonatal Mice Using Gavage
10:36

Probiotic Studies in Neonatal Mice Using Gavage

Published on: January 27, 2019

21.2K

Associations between the infant gut microbiota and the living environment

Brandon Hickman1, Anne Salonen1, Kaija-Leena Kolho1,2

  • 1Human Microbiome Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland.

Gut Microbes Reports
|March 30, 2026
PubMed

Insights

The early-life gut microbiota is minimally impacted by the natural environment. Air quality showed the strongest association, suggesting pollution may indirectly influence infant gut bacteria and immune system development.

Area of Science:

  • Environmental Science
  • Microbiology
  • Pediatrics

Background:

  • The human gut microbiota plays a crucial role in host health and development.
  • Early-life microbial colonization is critical and can have long-term effects.
  • The influence of the natural environment on infant gut microbiota remains poorly understood.

Purpose of the Study:

  • To investigate the association between the postnatal home environment and the infant gut microbiota.
  • To determine the extent to which environmental factors shape gut microbial composition in the first two years of life.

Main Methods:

  • Analysis of 16S rRNA gene sequencing data from 893 infant fecal samples.
  • Utilized data from the longitudinal HELMi birth cohort study.
  • Examined environmental factors surrounding participants' homes.

Main Results:

  • The overall association between the environment and microbiota development was minimal (R² < 1%).
  • Air quality was the most significant environmental factor influencing microbiota composition.
  • Proximity to forests, agriculture, and inland wetlands showed minor associations with specific bacterial genera.

Conclusions:

  • The infant gut microbiota is not strongly dependent on the external natural environment.
  • Air pollution exposure appears to be the primary environmental driver, potentially impacting the host immune system and indirectly the gut microbiota.

Keywords:
Infant gut microbiotaair pollutionenvironmentland use

More Related Videos

Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing11:22

Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing

Published on: October 15, 2019

31.6K
An Intestinal Gut Organ Culture System for Analyzing Host-Microbiota Interactions05:27

An Intestinal Gut Organ Culture System for Analyzing Host-Microbiota Interactions

Published on: June 30, 2021

5.2K

Related Concept Videos

Development of Human Microbiota01:30

Development of Human Microbiota

The human microbiota begins developing at birth and undergoes continual change as we age. Infancy marks a critical period of microbial sensitivity, offering a “window of opportunity” during which beneficial microbes help mature the immune system. By age three, children typically develop a more stable and diverse microbial community. Newborns acquire microbes from their immediate environment; vaginal delivery favors maternal vaginal microbes, while cesarean births favor microbes from...
34
Anatomy of the Intestines01:23

Anatomy of the Intestines

Although digestion of proteins, carbohydrates, and lipids may begin in the stomach, it is completed in the intestine. The absorption of nutrients, water, and electrolytes from food and drink also occurs in the intestine. The intestines can be divided into two structurally distinct organs—the small and large intestines.
Small Intestines
The small intestine is an ~7 meter-long tube with an inner diameter of just 2.5 cm. Since most nutrients are absorbed here, the inner lining of the...
91.5K
Development of the Oral Microbiota01:28

Development of the Oral Microbiota

The establishment of the oral microbiome begins before birth, challenging the long-held belief that the fetal oral cavity is sterile. The presence of oral microbes such as Streptococcus and Fusobacterium in amniotic fluid suggests that microbial exposure may occur in utero, potentially through translocation from the maternal oral or gastrointestinal tract. This early colonization primes the neonatal immune system and sets the stage for subsequent microbial succession. Maternal health,...
37
Gut-Brain Axis01:22

Gut-Brain Axis

The gut–brain axis is a bidirectional communication system that connects the gastrointestinal tract and the brain. This interaction is mediated through multiple pathways, including the vagus nerve, hormonal signals, immune responses, and chemical messengers produced by gut microbes.Microbial Contributions to Brain FunctionGut microbiota contributes significantly to brain function by producing neuroactive compounds. These include neuroactive compounds that influence neurotransmitters such...
54
Introduction to the Human Microbiota01:22

Introduction to the Human Microbiota

Microorganisms colonize various regions of the human body, including the mouth, nasal passages, throat, stomach, intestines, urogenital tract, and skin. The total number of microbial cells is estimated to range from 10¹³ to 10¹⁴—comparable to, or exceeding, the number of human somatic cells. This host–microbiome relationship has led to the conceptualization of humans as supraorganisms, wherein microbial communities perform vital roles in development, immunity,...
68
Microbiota of the Stomach and Small Intestine01:27

Microbiota of the Stomach and Small Intestine

The human gastrointestinal (GI) tract is characterized by distinct physicochemical conditions that shape its microbial communities. Among these, the stomach presents a particularly challenging environment for microbial colonization due to its highly acidic pH, ranging from 1 to 3. This extreme acidity effectively limits microbial density. However, certain acid-tolerant microorganisms are capable of surviving in this niche. Notably, Helicobacter pylori can colonize the gastric mucosa,...
43