The Human Immune System – Your Ultimate Guide

Updated on November 4, 2020

Right now, the need for a strong and healthy immune system has never been greater. 

We find ourselves in the grips of a deadly pandemic, the likes of which we’ve never witnessed before in our lifetime, and with any luck, the likes of which we’ll never see again when things do finally return to how they were at the start of the year. 

The Coronavirus sweeping the globe has brought the world to a standstill and left devastation in its wake, though if there are any positives to be taken from it, it’s the fact that it has highlighted the importance of a strong and healthy immune system. 

Though experts see the only real solution to this pandemic coming in the form of a vaccine, health experts are highlighting the importance of keeping your immune system strong, healthy, and functional. 

In truth, we should do what we can to strengthen the immune system anyway, simply because it can protect against so many ailments and health issues, which is why we’ve compiled this useful guide today. 

Below you’ll find everything you need to know about the human immune system. 

What is the immune system?

Put in very basic terms, the immune system is your body’s first and last line of defence against illness and disease. It is responsible for keeping you fit and healthy, and the stronger it is, the healthier you will likely be, and vice versa. 

That was the basic explanation, to get more technical, your immune system is comprised of a series of cells, tissues, organs, and molecules that stretch throughout the entirety of your whole body. Every single component from cell to major organ, has a role to play in keeping your body functional and ticking over as it should. 

The immune system’s primary role is to help protect us against invading pathogens such as germs, bacteria, fungi, toxins, and viruses which would attack us from the inside out and leave us unwell and potentially at risk of death. 

The innate and adaptive immune systems

If you speak to an expert about the immune system, you’ll find that the immune system is split into two sections: 

  • Innate immune system 
  • Adaptive immune system 

The innate immune system is designed to help protect the body against microorganisms which attempt to infect us, like the awful Coronavirus doing the rounds at the moment. The innate immune system is basically the equivalent of an army inside your body, as it is designed to seek and destroy invading pathogens and anything which doesn’t belong inside us. 

The adaptive immune system is slightly different, in that it functions almost like a memory card in a computer. If you’ve been keeping up with the latest on the pandemic, you’ll have heard experts talking about the importance of immunity and building up antibodies. This is where the adaptive immune system comes into play. 

The adaptive immune system helps to identify and recognize germs, bacteria, and pathogens and to raise the alarm to the adaptive immune system to signal that something isn’t right and to dispatch the troops, I.E your white blood cells and antibodies. Basically, the adaptive immune system remembers specific viruses and pathogens so that, if it encounters them again, it is better prepared to deal with them and eradicate them quickly. 

One of the main reasons why Covid-19 has caused so much chaos is due to the fact that it is a completely new virus, meaning that none of us have any immunity or antibodies. This makes it much easier for the virus to be spread, as it can jump from person to person, rather than jumping from one person and being wiped out by the immune system before it has chance to affect anybody else. 

So, how exactly does the immune system work?

To truly understand the ins and outs of the immune system, you’d need to be very informed when it comes to biology, physiology, anatomy, microbiology, and a whole lot more besides. As most of us don’t hold a PHD in these subjects, we’ll try to keep things as simple, yet informative, as we possibly can. 

Basically, a virus, or pathogen will sneakily make its way into the body, either through something we eat, something we touch, or even something we breathe in. Depending on what it is, it will attack us from within. 

The Coronavirus for example, has a series of protein ‘spikes’ on its exterior, which it uses to hook onto the proteins found on the surface of our human cells. Once the virus has attached itself to it, it begins to alter the membrane of the healthy human cell, allowing it to enter and get inside the cell. 

Now the virus uses its RNA (Ribose Nucleic Acid) to hijack the cell’s ability to produce proteins, and basically reprograms the cell to produce copies of itself. Now your cells are producing copies of the Covid-19 virus so it is replicating. Now these too infect other healthy cells in the human body and the process repeats itself over and over again. 

Now, here’s where things get interesting/worrying because with known viruses, once the healthy cells were under attack, the adaptive immune system would recognise the virus and would recognise that something was wrong and would sound the alarm. White blood cells which are known as B lymphocytes, which are basically the equivalent of soldiers, would be dispatched and would attack the pathogens with tiny proteins which are known as antibodies. Ordinarily, these antibodies would mark the invading pathogens, almost like fitting a tracking device, they would help protect healthy cells, they would neutralize toxins, and with extreme cases, they would alert the big boys of the immune system, which are T-cells, or T lymphocytes. This would be the equivalent of the National Guard alerting the Navy Seals and having them deal with the threat. 

The T-cells basically spear the invading pathogens with a substance known as perforin, which pierces the cellular wall of the bacteria, causing them to die. 

There is another immune cell known as a Phagocyte, which actually envelops invading bacteria and pathogens, utilizing enzymes to break them down and dissolve them. 

The problem with Covid is that, as yet, the virus prevents the cell serving as host from sounding the alarm and calling for help, so basically the immune system has no idea that your cells are being attacked. 

How to boost the immune system

As you can see, it’s vital that we make our immune system as strong and as healthy as we possibly can. The good news is that, even if your immune system is naturally weakened or not as strong as it could be, there are ways of strengthening and boosting it. 

Here are some handy tips for boosting the immune system naturally. 


According to, One of the best ways of boosting the immune system is to exercise on a regular basis. 

Exercise helps to reduce your risk of long-term illness and can increase your longevity, though it turns out that it can also improve your immune system as well. 

Experts have found that exercise helps to strengthen immunity, though they’re not quite sure how it does so as yet, but generally speaking the healthier your lifestyle, the healthier you will be and the stronger your immune system will be as a result. 

Get enough sleep 

One of the main reasons why people that are tired and run down often find themselves becoming ill is because a lack of sleep weakens the immune system. 

Sleep deprivation can cause a loss of muscle mass, it can lead to hormonal imbalances, it can lead to mental health issues, and it can weaken the immune system. 

Whereas there is no optimal sleep duration as each person is different, the general consensus is that we should aim for 7 – 9 hours of sleep each night to function at our healthiest. 

If you’re looking to boost your immune system, or even keep it healthy and functional, be sure to get enough sleep each night. 

Consume healthy produce 

The immune system thrives upon nutrients such as vitamins, minerals, and antioxidants, which is why it’s so important to consume healthy produce. 

Experts encourage us to consume vegetables and fruits because they’re packed full of vitamins, minerals, and antioxidants that help to strengthen the immune system and keep it functional. 

Limit your fast food intake, cut way back on processed junk food and instead eat fresh, healthy, and wholesome food containing plenty of vitamins and minerals. 

You may also consider supplementing with vitamins such as vitamin C and multivitamins, though these are no substitute for whole foods and should be consumed alongside healthy produce for best results. 

Try to manage your stress levels 

Right now, telling somebody to manage their stress levels during a pandemic is far from ideal, but whenever possible, stress should be managed or avoided as it can weaken the immune system hugely. 

Studies have found that stress can weaken the immune system, leaving you more susceptible to illness and disease. 

Find the time to do things you enjoy, remove yourself from stressful situations whenever possible, and find the time to relax and do things that make you feel good. 

Cut out alcohol 

Right now, thanks to the pandemic, the closing of bars, clubs, and pubs, along with lockdowns and stress and worry, more and more people are drinking excessively at home, and experts are worried about what this could mean long-term. 

Not only could excessive drinking lead to potential addiction issues, but it could also weaken the immune system. 

Excessive drinking can hinder immune function and increase your risk of illness and disease, so try to cut way back. 

We aren’t saying you should stop entirely because in moderation, an alcoholic beverage can be quite relaxing and enjoyable. In excess, though, it could leave your immune system compromised. 

So, what’s the bottom line on immunity?

As you can see, your immune system is hugely important for a variety of different reasons, though now it is more so than ever. 

The good news is that there are things you can do to enhance immunity, and those, combined with healthy living and preventative measures such as the wearing of face coverings, and frequent washing of hands can actually go a long way in ending this pandemic quicker, or at least keeping it under control under a vaccine becomes readily available. 

The Editorial Team at Healthcare Business Today is made up of skilled healthcare writers and experts, led by our managing editor, Daniel Casciato, who has over 25 years of experience in healthcare writing. Since 1998, we have produced compelling and informative content for numerous publications, establishing ourselves as a trusted resource for health and wellness information. We offer readers access to fresh health, medicine, science, and technology developments and the latest in patient news, emphasizing how these developments affect our lives.