Cesarean birth, formula feeding, and exposition to antibiotics might impact the baby’s growth, according to researchers from New York University (NYU). Those factors have been linked to a slowdown of development and a decrement of the baby’s diverse microbes within their first year of life.
Researchers focused on the microbiome, which is the combination of different bacteria living on human skin and guts. These microorganisms have co-evolved and are now part of digestion, metabolism, and immunity, said researchers in a press release issued Monday.
During the last decades, the presence of C-sections, antibiotic use and formula feeding has increased worldwide. At the same time, autoimmune diseases, asthma, and obesity have become a major public health problem.
Prior investigations had proposed there was a relationship between those factors. New findings have found a direct link between microbial differences and disease risk. Detailed results of the study were published on Tuesday, June 15, in Science Translational Medicine.
Results from the study determined that “modern practices” alter the way microbial communities are developed among babies during the first year of life, according to Martin Blaser, Professor of Translational Medicine at NYU School of Medicine.
“The big, remaining question is whether or not changes in this timeframe, even if resolved later on, affect the founding of microbiomes with lifetime consequences for a child’s immune function and metabolism,” added Blaser.
The reasons for links seen between microbial changes and many diseases remain unclear
A team of researchers has analyzed the impact of modern practices such as C-sections, and formula feeding, on intestinal microbiota development of 43 children from New York. Results demonstrate that changes in the gut microbiomes and feeding methods can be related.
A new theory proposed that “altered microbiota assembly” may be linked to the development of diseases, said Blaser, who is also a professor at NYU Langone. Researchers collected more than 1,000 stool samples per month, from 19 babies born by cesarean and 24 by vaginal delivery.
Bacterial DNA obtained from the samples was analyzed, to identify the microbiome of each participant baby. The effect of antibiotic use and formula feeding was studied for the first two years.
The whole population of microorganisms of the skin and other body parts is termed as the human microbiome. #HumanAnatomy
— Easy Anatomy (@EasyAnatomy) June 15, 2016
The use of antibiotics right after birth alters diversity of bacterial species
Researchers concluded that babies born by C-section “displayed significantly greater species diversity” during the first weeks of life, in comparison to those born by vaginal delivery. However, results changed during the following two years, when the first group showed lower diversity.
Antibiotic use was also studied among newborns. Results demonstrated that antibiotic treatment may be linked to a decline of bacterial species right after birth. During the following two years, diversity continuously recovered to resemble the one shown by infants who were not exposed to the drugs.
Children exposed to antibiotics and formula-feeding instead of breast milk showed “delayed microbiota maturation”.
“The change in birth mode interrupted the natural interplay between diversity and dominance,” said Blasser in a press release.
Just started reading the book for my human microbiome class & I already want to live in a plastic bubble
— Amanda Little (@amanda__little) June 5, 2016
Source: NYU Langone Medical Center