The impact of being breast or bottle-fed for babies is an age-old debate, but a new study by the Technical University of Munich has looked at the gut health of 200 babies over two years.
The study looked at the gut health of different groups of babies – breastfed, formula-fed, and those with different things added into formula.
The research found the bacteria in a baby's gut develops in a similar way whether they're breast or formula fed – but with important differences too.
University of Auckland Paediatric Endocrinology Professor Wayne Cutfield told AM about 15 years ago it was found humans had lots of bacteria in our gut.
"There are more bacteria in our gut than cells in our body," Prof Cutfield said.
"We realised these bacteria are actually helpful to us. Unlike most bacteria that cause infections, make us sick and kill us. These bacteria help our health, our wellbeing and can even influence our behaviour."
He said gut health was "one of the hottest areas in medical research" at the moment.
The German study on 200 babies looked at their gut bacteria over the first two years. By those two years, researchers found no differences in how the gut bacteria looked.
However, while the bacteria looked the same, it was behaving differently, Prof Cutfield said.
"Really it's how the bacteria behave, how we behave, that matters - not how we look. So, there clearly are differences," he said.
Prof Cutfield explained that one important component in breast milk was the sugars - more common than protein in the milk - which feed the good gut bacteria.
"That's their principle role, to nourish the best bacteria to get babies off to the best start… they are really helping to set our gut bacteria up.
"We know for example that those milk sugars in our gut bacteria, healthy gut bacteria, early on reduce the risk of obesity in childhood, reduce the risk of allergic diseases – asthma, eczema – and other immune conditions."
Prof Cutfield said there were also bigger studies in this space which look at things, including the gut microbiome.
"There's just so much more for us to learn about our gut microbiome," he said.
"The field's in its infancy and once we start doing trials where we give people a healthy gut microbiome who have certain conditions do we really understand what difference is it truly going to make to us."
