We all have bacteria living in our guts. They help us break down foods and fight off bad microbes. We’re not born with these microbes, but acquire them from our mothers during the first year of our lives. A recent study by David Relman and colleagues has found that baby’s first microbes play a lasting impact throughout their lives. The study focused on fourteen babies for one year. During this time researchers took fecal samples (poop) from the babies. They also took fecal, breast milk and vaginal samples from the mothers. They extracted the microbial DNA and compared genetic sequences. The results showed that babies acquire their first microbes as they first enter the world. Some microbes resembled the mother’s vaginal sample or breast milk and one baby’s microbes resembled the mother’s feces (Ewww!).
All the babies had different intestinal microbes in the beginning, but by the end of year one the populations were very similar and started to resemble those of adults. Each baby still retained their own signature microbes which were probably started by their first exposures to germs along with diet. This shows how early events mould adult microbe populations. Two babies in the study were given antibiotics which dramatically changed their intestinal microbe population. Researches for the study said that these babies never returned to the populations they had before the antibiotics.
This study says a lot about how we handle certain foods as adults. The researchers want to continue this study and add babies born by cesarean to the mix. Who knows? It may turn out that babies born by cesarean are more likely to be lactose intolerant because of the microbes they were exposed to at birth.