Everything starts in the gut. The infant microbiota plays an essential role for health and a diverse microbiota may contribute to better health later in life.

What is the microbiota and why is it important?

Microbes live on and within us, mostly in a mutually beneficial relationship. Approximately 90- 95% of these microbes are found in our gut. The intestinal flora, or microbiota, is like an ecosystem of different microorganisms and consists of trillions of bacteria belonging to thousands of different species. 

The microbiota helps us digest food, regulate the immune system, fight harmful bacteria, produce vitamins and other important substances and break down toxins from drugs or other sources. An unbalanced intestinal flora can lead to a wide range of problems. Everything from stomach issues to skin problems, difficulty sleeping, problems with our well-being and impaired resistance to infections.

The microbiota of infants and children

Infants establish their gut bacteria and intestinal microbiota at birth and through the first three years of life. Babies are almost completely sterile at birth, but immediately thereafter bacteria start to colonise their mouth, their skin, their gastrointestinal tract and every other part of their body. The amount and diversity of bacteria continue to increase until the age of three. After the age of three, the child’s microbiota is more stable and largely resembles the composition of an adult’s. So what affects what kind of microbiota a person establishes in those first, critical years of life?

Baby’s first gut flora - how the microbiota develops in infants

Bacteria acquired at birth

Already during pregnancy, the lifestyle, diet and the microbiota of the mother play a role for the unborn child. Different components are transferred across the placenta helping to prepare the baby for life after birth. However the first and most important factor affecting a baby’s microbiota is how they are born. Babies born vaginally acquire bacteria directly from their mothers as they pass through the birth canal. Whereas babies born via caesarian section primarily pick up bacteria from their mothers’ skin and the hospital environment, and they tend to have less beneficial bacteria overall in the first days and weeks of life. The use of medication such as antibiotics during and or directly after delivery also affects the composition of the infant microbiota.

Bacteria acquired via breastfeeding

After birth, breastfeeding, bottle-feeding with expressed breastmilk, and/or formula-feeding are the second major factor affecting the baby’s gut flora. Breastfed babies have an abundance of bifidobacteria which consume oligosaccharides - special sugars that are found in breast milk and that can only be digested with the help of bifodobacteria. Other beneficial bacteria such as lactobacillus are passed on from mother to the baby during breastfeeding. Baby formula is formulated to mimic breast milk as closely as possible.

Children’s gut flora - the first three years

Beyond the newborn stage, a small child’s microbiota is affected by factors such as sleep, exercise, food, medications and environment. 

First foods

When babies start to wean and experiment with solid foods at around six months of age, there is a window of time when they tend to be relatively open to new tastes and textures. A varied diet, with lots of fruits and veggies in every colour of the rainbow, is very beneficial to gut health. At around 12 months of age, children often become more hesitant to try new things. So it’s a good idea to make the most of this early window in order to lay the foundation for a gut-healthy diet throughout life.

Environment and excessive cleanliness

Environmental factors that affect a child’s microbiota include being raised in an urban or rural environment. Having pets and other animals around are known to be beneficial whereas excessive cleanliness actually negatively affects our microbiotas. A certain amount of dirt is actually of benefit for children.

Medication

Medications such as antibiotics used to treat bacterial infections have a huge effect on the microbiota. Antibiotics wipe out both bad and good bacteria, so if antibiotics are needed to treat an infection it’s a good idea to take a high-quality probiotic supplement in connection with the treatment. Just make sure not to take the probiotics and antibiotics at the same time (leave a few hours between them), or the antibiotics will kill off the probiotics before they have a chance to establish themselves in the gut. Small children can take probiotics in the form of tummy drops.

What can you do to support the development of a healthy microbiota in your child?

For the most part, a healthy microbiota in children is supported in the same way as we support our health in general. however for infants and children it is especially encourage to:

• Spend time outside everyday 
• Do what you can to make sure your child gets enough sleep
• Only use antibiotics when really needed
• Introduce your child to a varied diet with lots of fruits and vegetables after 6 months of age
• Support a healthy gut flora with a daily probiotic supplement