How does your immune system protect you?



Qualified Nutritionist (BSc, MSc, RNutr)
@emmatalkshealth
@EmmaThornton
Ask Emma


29 April 2021

How does your immune system protect you?

Your immune system helps protect you via the 'innate' branch which you acquire even before you are born and the 'adaptive' part which you build up throughout your life. Plus, there is also the addition of vaccine-acquired immunity, which protects us by producing the necessary antibodies to help fend of invading pathogens which can make you sick.

The ultimate aim is for the immune system to differentiate between ourselves and foreign invaders, protecting us from harmful pathogens, but also to understand which foreign substances can be considered harmless and therefore preventing unnecessary inflammation.

 

What are the different parts of the immune system?

The immune system can broadly be split into two main parts, or sub-systems which work hard in a unified approach to help protect us from falling ill. These are as follows:

1. The innate immune system

From as soon as we born (actually, technically even before this) we possess some innate (natural) immune defences which are in place to help protect us. Our skin, for one, acts as an initial line of defence in the form of a barrier, as does our stomach acid which can be classed as a secretion. Then, from this point onwards, the cells of our immune system also start developing and advancing so they can start to recognise and fight foreign particles which may pose a threat to us.

Interestingly, the innate arm of the immune response is considered the much older, ancient and evolutionary preserved arm of the immune response. Many of the constituent components are actually conserved across a number of different species, with us even sharing some similar immune properties to fruit flies, in some respects! But this just proves that these complex mechanisms really work, helping to protect us all.

2. The adaptive immune system

The adaptive (acquired) immune system is a highly complex system that continues to change and adapt over the course of our lives.

Over time your immune system acquires special memory cells which mean we can help build immunity to bugs we've already come into contact with, so we might not be so sick if we were to come into contact with them again. Cleverly, this could also potentially stretch to include even very similar bugs or strains, to the original infection.

Inflammation is an important part of our immune response too. Inflammation at the sight of injury by a bug or virus, signals to your immune system that help is required. Then, special immune signalling cells, such as chemokines for example, direct white blood cells into the area (this is why redness and swelling can occur) where different immune cells such as macrophages can then engulf the invading pathogens and kill them off. This is a simplistic view of course, a number of immune cells are involved in making this process effective such as cytokines, B cells, T cells and dendritic cells.

Following clearance of the pathogen, the adaptive immune system then plays two important final roles. Firstly, all going well, it switches off the global immune response to help prevent ongoing unwanted inflammation, but secondly it forms a memory of the pathogen, in a bid to prevent any repeat infections in the future.

It's also important to note how well the innate and adaptive arms of our immune system work so well in seamless harmony. Our innate immune response is extremely quick-acting and is elicited within seconds of detecting a pathogen. It has the main role of curtailing the early disease dissemination and damage, whilst working away nicely in the background, we also mature the more tailored adaptive arm of the immune response which then mops up the remaining infection and provides protection in an ongoing manner.

Immunisation – how does it play a part?

Interestingly, documented evidence of vaccine approaches date back over three thousand years to the time of Ramses V, where scarification, a crude form of vaccination was first explored.

The vaccine is a clever way of manipulating adaptive immunity to provide us long term protection in the absence of initial disease. Scientists can use their knowledge of our adaptive immune response in order to help protect us from infections that we, as individuals, have often not yet even come into contact with.

Immunisation programmes use vaccines to encourage your immune system to generate a collection of specific cells and antibodies to protect you from future infections such as coronaviruses, giving you a better chance of fighting off these very bugs, if you were ever to then come into contact with them.

Vaccines also work by introducing parts of pathogens (antigens) to you in such a way that you don't become too sick, but crucially still produce antibodies. These antibodies can then help to protect you if the same threat should reappear.

How can you help your immune system protect you?

Whilst immunity is to some degree in-built and then adapts and changes as we go through life, there are also dietary and environmental factors which can influence how well your immune system operates.
Therefore, in order for your immune system to be able to protect you, we need to look after it so it can work to the best of it's potential. Some of the best ways to do this are as follows:

1. Follow a good diet

Research suggests that certain nutrients can encourage your immune system to work optimally such as vitamin C, zinc and vitamin D. Vitamin C is an antioxidant which can help to protect your immune cells from damage by free radicals (1), zinc is crucial for the normal function and development of immune cells (2) and vitamin D is very good at modulation functions. (3)
However, there are also some aspects of our diet which could risk hindering our immune responses. Alcohol, especially in excess, may deplete functions of the immune system making it less able to protect you, (4) whilst refined sugar may compete with some of the more positive effects of vitamin C.

A small note on food hygiene

There are some steps we can take when handling and preparing food in order to help your immune system out; as there are just some instances when no matter how good our immunity is, some types of bacteria for example, could still make us ill before your immune system was able to get them under control.

Basic principles of food hygiene such as separating raw and cooked food, reheating food properly and storing food in the correct conditions can all help ensure your immune system has a better chance of keeping you well.

2. Get enough sleep

Sleep is arguably one of the most important steps you can take to help ensure your immune system is able to function optimally. When you are sleeping and in a relaxed state your 'rest and digest' functions are able to operate more fully, including many aspects of the immune system. (5)
Symptoms of stress often go hand in hand with poor sleep and can also ultimately affect how your immune system operates. Short-term or eustress isn't so worrisome but if stress become long-term or chronic, your immunity may suffer as a result. (6)

3. Look after your digestion

Your immune system is an intricate system which patrols almost every inch of our body and comprises various immune cells such as dendritic cells in order to carry out its work. Up to 80% of these clever immune cells are thought to reside in your gut, which is why looking after your digestion is also top priority when it comes to achieving optimal immune health.

Chewing your food properly and using digestive bitters are just some of the ways you can help support our digestion, which in turn, can help limit any negative impacts on your immune system.

4 - Herbal helps

Whilst diet and lifestyle factors are key for supporting your immune systems, additional herbal remedies can also be an excellent option if you feel you need a little helping hand.

Echinaforce echinacea can help to reduce the symptoms and duration of your symptoms if you have a current cold or flu infection, but it may also help to strengthen your immune system by supporting your resistance to infection.

Echinaforce® Echinacea Drops

15ml

£ 4.99

Buy now

For relieving the symptoms of colds and flu. Also in 50ml & 100ml drops.
More info

A.Vogel Echinaforce Echinacea Tablets relieves cold & flu symptoms by supporting the immune system

42 tablets

£ 5.49

Buy now

For relieving the symptoms of colds and flu. Also in 120 tabs.
More info

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