Researchers from the Stanford University School of Medicine collected more than 500 stool samples from 14 healthy, full-term babies during their first year of life.
Before birth, a baby’s gut is sterile and completely free from microbes. Within days, helpful microbes establish a thriving community that soon outnumbers the baby’s own cells 10-fold – a ratio that persists throughout life.
By the end of their first year, each baby had a unique intestinal ecology that harbored societies of microbes similar to that found in adults’ intestines.
These microbes play critical roles in health, including processing nutrients, defining host body-fat content and providing protection against infection.
This study helps uncover the range of what occurs in the guts of healthy babies born to healthy mothers. Future studies could explore the roles genetics and environment play in the development of these microbes, such as how the microbial environments of breast-fed babies compare to formula-fed babies.