The immune system can broadly be split into two main parts, or sub-systems which work hard to help protect us from falling ill.
The immune system has 3 key lines of defence which work hard to help protect you from falling ill:
1 – The innate immune system
From as soon as we born (arguably 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 an effective barrier, just like stomach acid secretion. Already in the first days of life, the cells of our immune system also start developing and advancing. They can already start to recognise and fight foreign particles which may pose a threat to us.
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. The aim is for the immune system to differentiate between ourselves and foreign invaders, but also to try and understand which invaders may be harmful and which instead can be considered harmless.
Also, over time your immune system has special memory cells which mean we can help build immunity to bugs we've already come into contact with. This has the effect, that we do not get so badly ill when we come into contact with them again.
Inflammation is an important part of our immune response too. When there is an attack by a bug or virus, an inflammation signals to your immune system that help is required. Then, special immune signalling cells, such as cytokines for example, direct white blood cells into the affected area (this is why redness and swelling can occur). There different immune cells such as macrophages can then engulf the invading pathogens and kill them.
This is a simplistic view of course, a number of immune cells are involved in making this process effective such as e.g. cytokines, B cells, T cells and dendritic cells.
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 our immune system to be able to effectively protect us, 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 – 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). Refined sugar, e.g. consumed in excess with sweet drinks, may compete with some of the more positive effects of vitamin C.
A small note on food hygiene
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 that the foods we consume give our immune systems the right boost to keep us healthy.
2 – Enough sleep
A sufficient amount of sleep is arguably one of the most important steps you can take to help ensure your immune system is able to function optimally. When we are sleeping and in a relaxed state our 'rest and digest' functions are able to operate more fully – and this in turn affects 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 – Good digestion
Your immune system is an intricate system which patrols almost every inch of our body and compiles various immune cells such as dendrites in order to carry out its work. It is assumed that 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 (alcohol-free) digestive bitters are just some of the ways that get our digestion going and thus indirectly support our immune system.
4 – Targeted support from medicinal plants
Whilst diet and lifestyle factors are key for supporting your immune systems, additional herbal remedies can also additionally support. Echinacea purpurea, for example, has an excellent immunomodulating effect.