Antibiotics, Formula Feeding Might Change Baby’s ‘Microbiome’

When babies are born, the birth process covers their bodies with countless microbes that play crucial roles in their future health. But a new study suggests that these “microbiomes” are altered by cesarean births, antibiotics and formula feeding.

“The microbiome is really important in how a baby develops normally. We are doing things that are disrupting them,” said Dr. Martin Blaser, director of Human Microbiome Program at New York University Langone Medical Center.

Microbiomes evolved with humans and are mostly helpful, explained Annie Gatewood Hoen. She’s an assistant professor of epidemiology and biomedical data science at the Geisel School of Medicine at Dartmouth, in New Hampshire.

“These organisms help digest our food, train our immune system and out-compete disease-causing microbes,” she said. But, there’s still a lot of mystery about how they work.

“They’re very complex and everyone’s is slightly different,” Hoen said, and it’s not entirely clear what healthy ones should look like.

“There is a lot left to discover about how subtle variations in the makeup of these communities might be more or less optimal for health and, importantly, how we can manipulate them so they’re most beneficial to us,” she added.

The new study examined the microbiomes of newborns after they left the sterile environment of the womb.



Blaser and his colleagues used stool samples to tract the intestinal germ makeup of 43 U.S. infants during the first two years of life. The researchers also analyzed the microbiomes of their mothers.

The investigators found that antibiotic use, cesarean birth and formula feeding all threw off the makeup of the microbiomes form levels considered normal. In essence, their make-up became less diverse, Blaser said.

“We didn’t measure health effects, so we can’t say whether that’s good or bad,” he added.

However, previous research has linked C-sections and antibiotics to higher rates of digestive illness, obesity and asthma, Blaser noted. And doctors recommend breast-feeding over the use of formula for similar reasons.

What’s next for research? In the future, it may be possible to counteract things that disrupt the microbiome, Blaser said. For now, “we’re continuing to follow these children”.

The studies were published June 15 in the journal Science Translational Medicine.

My Take:
We’ve known for a while that the microbiome is dependent on our genetics, where we are raised geographically, and our diet. Add to the list our birth process, breast-feeding versus formula, and antibiotic use in infancy.

We can already counteract things that disrupt the microbiome. The use of prebiotics in the form of soluble fiber is the most effective tool currently. You can support your microbiome with a diet rich in plant food as all plants contain soluble fiber.

Unfortunately, the indiscriminate use of probiotics, like antibiotics is also having a negative effect on the microbiome. As Professor Hoen noted the microbiome is “very complex and everyone’s is slightly different.” So picking is probiotic is guess work and best and an assault on the immune system at worse.

The Bottom Line:
Give your child the best start by providing a natural childbirth and breastfeeding. Avoid antibiotic use whenever possible (which is most of the time) and introduce them to a plant-food based diet as their digestive tracts mature.

June 15, 2016 National Institutes of Health