"Happy baby in a striped onesie crawling on a soft carpet in a brightly lit room, with toys and furniture in the background.

How does a child's immune system work?

The development of a child's immunes system takes time. The first years are crucial for its development.

Smiling mother holding her happy baby, who is looking at the camera, both enjoying a tender moment

The immune system matures with the baby

When children come into the world, their new immune systems are not yet fully mature.

While their non-specific immune system is already in place, the specific immune system will continue to mature throughout childhood. The first 1000 days of life (from conception) are crucial in this process, as the gut microbiota develops and lays the foundation for immune function and health in later life.

Illustration of a pregnant woman wearing a yellow dress and orange shoes, smiling and holding her belly

From conception onwards

Of course, babies require a little help with this at the start, and the mother does so by giving her child some of her own immune defence, also known as passive immunity.

This begins while the baby is still in the mother’s womb, where she passes antibodies on to her unborn child via the placenta. Then, during vaginal birth, the newborn receives a dose of bacteria from the mother’s birth canal. Breast milk also provides an initial supply of antibodies present in the mother's environment. This passive immunity offers a foundation for the child’s own highly effective defence network, which will accompany them for a lifetime.

Baby playing with a colorful bead maze toy while sitting on a carpeted floor in a brightly lit room.

Every beginning is hard

During these first 1000 days and beyond, children’s bodies and their developing immune systems constantly encounter new microbes – be it through contact with siblings or other children at playgroup, day care, or later at school.

This constant exposure can result in more frequent infections in the early years, with the average child experiencing 6-12 of them with cold-like symptoms a year. However, these continuous encounters help build up their immunological memories as their bodies’ immune cells learn from each case. While this process lasts a lifetime, their bodies are soon able to recognise the most frequently encountered microbes. This gradual adaptation means that children’s immune systems usually become stronger as they move towards adulthood.

Illustration of a shield with probiotic bacteria inside, symbolizing protection, set against a yellow circular background

The role of the gut system

The gut microbiota trains the immune system and plays a key role in creating normal functioning immune defence mechanisms.

The intestinal flora, including bacteria such as lactobacilli and bifidobacteria, begins to develop during birth and shortly after. The microbial transfer that takes place during vaginal birth means that bacteria start to colonise the newborn right away, giving their gut flora something of a jump-start. As such, children born by Caesarean section often show differences in their intestinal flora. Here, supplementation with probiotic bacteria as found in BioGaia drops could help keep an appropriate concentration of their natural gut microbiota.

Baby in a striped onesie taking assisted steps while being held by an adult's hands, in a brightly lit room with toys in the background

How can I support my child’s immune system?

The childhood years are crucial in the development of the entire immune system. Here are some tips on how to support it.

A balanced diet with a mixture of seasonal fruit and vegetables provides a lot of the nutrients a child’s immune system needs. Whole grains contain fibre – helpful for the normal function of the gut.
 

  • Time outside! Fresh air and plenty of movement are great for our immune systems and also encounter stress
  • Exposure isn’t always bad. Children need some exposure to external agents to build up their immunological memory. So, don’t disinfect everything.
  • Sufficient sleep and breaks during the day are crucial for reducing stress, allowing the immune system to do its job.
The role of Vitamin D

The role of Vitamin D

Unlike other vitamins, the body can produce vitamin D itself. For this reason, it doesn’t act like most vitamins in our bodies, but instead more like a hormone – a messenger substance that regulates essential physiological processes.

Infection Protection

Infection Protection

During this time of their lives, children are constantly experiencing new things and embarking on new adventures. New surroundings, new friends, new experiences - every day, children see and learn something new. As they make their way through school, their bodies are continuously confronted with new microbes.