Dr Phil Kieran: What can I do to boost my child’s immune system?

The immune system is an incredible and complex system.

My four-year-old seems to have picked up every bug in the crèche since September. He’s a great little fighter and has recovered quickly from each. What can I do to boost his immune system, so he doesn’t get sick so easily?

Children and crèches are a perfect storm for bugs.

Pre-schoolers or young, school-age children will get between eight and 12 viral infections per year. I inform parents of this fact in my surgery on an almost daily basis.

However, knowing this and experiencing it are two separate things. I can still vividly remember when my children seemed to spend as much time not going to go to the crèche due to illness as they did actually being there.

The immune system is a collection of interlocking processes that evolve throughout our lives. It is an incredible and complex system.

In the first months of life, a baby’s immune system is ramping up in almost every area. Significant protection is provided by antibodies that cross the placenta before the baby is born, protecting them from illnesses to which the mother is immune. During this period, we vaccinate against a number of significant childhood illnesses, many of which used to contribute heavily to infant mortality.

Helping your child’s immune system by vaccinating them is one of the most important things you can do. As the child grows, their immune system becomes increasingly robust and better able to deal with threats.

This progression also coincides with the time when they are more likely to be in close contact with more people.

However, the frequency of coughs, colds, and high temperatures increases when they begin spending time in environments with many other children.

As you have noted, your son tends to recover pretty quickly from each illness. This shows that he likely doesn’t have any underlying conditions, such as asthma, that would put his immune system under pressure.

There isn’t any guaranteed way to prevent children from getting so many infections per year.

Still, it can help to remember that these infections are helping their immune system build a ‘catalogue’ of responses that will improve its ability to fight similar infections in the future.

Joining a group environment will nearly always lead to more infections in the immediate, but it tends to mean fewer infections in the future.

For example, children who don’t go to pre-school get more illnesses in junior infants, and those who have older siblings in crèche or school tend to get fewer when they start.

Here are steps you can take to help your child’s immune system:

1. Make sure they get enough sleep: A four-year-old needs about 12 hours of sleep per night and possibly a nap in the day. Prioritising sleep is essential for the immune system and every other aspect of health.

2. Try to eat a varied diet: I know we all sometimes struggle to get children to eat healthy foods, but make sure they drink enough water and eat fruit and veg.

3. Supplement with vitamin D from Halloween to St Patrick’s Day: This is the only vitamin I tell people to make sure they take.

4. Start to teach your child good respiratory etiquette: Covering their mouth and nose when they sneeze or cough, and washing their hands before meals, can help. This won’t be reliable in a four-year-old, but it’s never too early to start good habits.

This period of frequent infections can feel overwhelming. Just remember that this is his immune system learning how to protect him, so keep telling yourself, ‘This too shall pass’.

• If you have a question for Dr Phil Kieran, please send it to [e-mail]