What is immunity and how does it work?

What is the immune system

Your immune system is the complex set of cells and functions that help to keep your body healthy1. It’s nothing short of incredible and without it, anything that might be harmful to your body could negatively impact your health, no matter how small or minor. 

Most of the time, you’re probably not even aware of the incredible job your immune system is doing to protect you around the clock - no complaints, no drama. Here we’re exploring exactly how your immune system works and how you can support it. 

How does the immune system work?

Your immune system is always on. When working effectively, it’s constantly on the lookout for anything that doesn’t belong to your body that might negatively affect your health. 

The immune system has two main parts; the innate and the adaptive. Both work closely together to provide our bodies with the protection they need2.   

The innate immune system - a fast and effective responder

The innate immune system comprises your skin, mucous membranes, proteins and special immune ‘defence’ cells. In addition, tears, sweat and stomach acids are also good examples of chemical barriers within the innate immune system. These act as a barrier to anything that might be harmful to your body. If anything does manage to get through, sensing that something is not entirely as it should be, your body’s defence cells immediately get to work protecting your health.   

The adaptive immune system - a direct and targeted response

Sometimes, things get past the innate immune system, leaving the adaptive immune system to take over. While its response is slower, it’s also very clever! It uses antibodies produced by memory immune cells to identify and remember any harmful intruders so that should they return at any point, your immune system can respond faster.   

How to support your immune system

There are lots of things you can do to proactively support your immune system in its job of keeping you healthy.  

Sleep and diet are two great examples.   

Sleep and the immune system

 On average, adults need between 7 - 9 hours of sleep per night, whilst children require between 9 - 133. When you’re asleep, your immune system is still at work producing the antibodies and proteins that form part of your body’s immune response4. That’s why  a good night’s sleep is crucial.  

Diet and the immune system

A varied and well-balanced diet is also essential for supporting your immune system.  This is because it provides the energy and nutrients your body requires daily to keep you healthy. These include vitamins B6 and D and zinc, selenium, and iron5.   

  Wholegrain and starchy foods, fish, meat and pulses and plenty of delicious fresh vegetables and fruits form part of a healthy, well-balanced diet. You’ll also need to consume some milk and dairy products or dairy alternatives such as soya6. You could try Actimel yogurt shots containing vitamins D and B6, which are known to support the immune system's normal function. 

What weakens the immune system?

Because your immune system is such a superstar, it’s only natural to try and find the best ways to protect it.  

Lack of sleep, a poor diet and an unhealthy lifestyle are all factors that can negatively affect your immune system. Your body simply can’t function at its best when you're tired, inactive and not getting the immune-supporting nutrients that you need.  

There are a number of things you can do to support your immune system and keep it healthy. You could try:  

  • Setting yourself a sleep schedule to get at least 7 hours a night.  

  • Eating a healthy balanced diet and planning your meals to include immune-support foods.  

  • Incorporating exercise, such as a daily walk, into your routine to get your body moving.  


*Actimel Core, Plus, Dairy Free & 00 range contain Vitamins D and B6 to help support the normal function of the immune system. Actimel kids contains vitamin D to support the normal function of the immune system in children. **Actimel 0% Fat 0% Added Sugars : No added sugars, contains naturally occurring sugars. ***Except for Actimel Kids range. ****Vitamin B6 contributes to normal energy-yielding metabolism. △RI: Reference intake of an average adult (8400 KJ/2000 Kcal) (as per Food Information Regulations). Enjoy as part of a balanced diet and healthy lifestyle.