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Home » Boosting the immune system – that’s what vaccines do

Boosting the immune system – that’s what vaccines do

Last updated on August 24th, 2019 at 04:38 pm

Immune system myths are one of the common claims of the junk medicine crowd, especially the anti-vaccine activists. The pseudoscience of the immune system is pernicious and possibly dangerous.

It’s frustrating that the pseudoscience from the junk medicine crowd claims that this supplement or that food is critical to boosting the immune system – hang out for a day on Facebook, and you’ll probably see way too many memes saying that all you have to do to boost your immune system is eat a blueberry kale smoothie. I still see that dumb banana claim that it cures cancer.

The problem with these immune system myths is that they overlook or ignore a basic physiological fact – the immune system is a complex interconnected network of organs, cells, and molecules that prevent invasion of the body by hundreds of thousands, if not millions of pathogens and other antigens every single day.

And no matter how much individuals try to trivialize the complexity of the immune system, it does not make it so. One can claim all day long that downing a few tablets of echinacea will boost the immune system to prevent colds (it doesn’t), it doesn’t make it scientifically accurate. Nor does it create an accurate description of the immune system.

The science of the immune system

Now comes the science part of the article. I, and others, always complain that the junk science world massively oversimplifies the mechanisms of the immune system. Simplifying complex science makes it easy to consume – but it is a fundamental aspect of pseudoscience.

The junk medicine pushers attempt to characterize the immune system as a one pathetic, weak, hardly functional little organ – which it is not.

In fact, the immune system is a huge, complex, interrelated bunch of biomolecules, cells, tissues, and organs, usually all working in harmony. And it’s pretty resilient. If the immune system was such a weakling, we would all be dead from pathogens before we made it to our 5th year of life. And there is a reason, why we make it past your 5th year of life, but I’ll get to that.

So, if someone says “this boosts your immune system,” your first question must be “which of the thousands of different parts of our immune system is boosted?”

Your second question should probably be “do you have a peer-reviewed extraordinary evidence that supports that extraordinary claim?”

Let’s get all science-y and describe the immune system. Admittedly, I’m writing this not only to be informative but also to overwhelm the notion that the immune system is some simplistic entity within the body.

Here we go:

Parts of the Immune System

Part 1. The innate immune system – This part of the immune system includes its ability to prevent or detect foreign material, then eliminate it without an antigen- or pathogen-specific physiological response of the body. It is the body’s quick and initial general response to disease-causing organisms (pathogens) which invade our body.

The innate response works in one of two ways: first, it directly prevents an infection, such as the skin blocking bacteria from entering the bloodstream. And second, it delays the invasion sufficiently for the slower but more effective and selective adaptive Immune system to activate its response to the pathogens.

But the innate immune system isn’t a simple thing, it is extremely complex, consisting of:

  • Anatomical barriers–These consist of physical barriers. One of the best examples is the skin itself, which is impermeable to pathogens providing defenses like a solid wall. There are many other examples that are very apparent like hairs in the nose, or mucous.
  • Inflammation–This response includes the symptoms we associate with inflammation – fever, swelling, increased blood flow, repair of damaged tissue, and removal of foreign and dead tissue.
  • Complement SystemThis system is a group of biochemicals, produced by the liver, that helps or “complements” the ability of antibodies and phagocytic cells to clear pathogens from an organism. It is part of the immune system that is not adaptable and does not change over the course of an individual’s lifetime. However, it can be recruited and brought into action by the adaptive immune system.
  • CellsMostly white blood cells (WBC) are involved in the innate immune system:
    • Mast Cells – A group of cells that mediate the inflammatory response. Although they are often associated with allergies, they are a critical part of the immune response.
    • Phagocytes – Large cells that move like an amoeba. They “eat” other cells by surrounding them with their plasma membranes producing “bubbles” in which they can release enzymes safely without damaging other cells. They also have a “clean-up” role to remove the body’s dead and dying cells.
    • Macrophages – Large phagocytic cells that efficiently consume multiple pathogens. Heavily motile and actively cross from the bloodstream into tissues to hunt down pathogens. They kill by manufacturing and releasing free-radical oxygen in a local area.
    • Neutrophils/Eosinophils/Basophils  A group of similar cells that are the “first responders” to migrate to an inflammation site. They appear at the site of a wound within a few minutes of trauma.
    • Natural Killer Cells – These cells recognize the body’s own cells that are infected by viruses or are cancerous. They then induce controlled cell death to halt the spread of the infected or cancerous cells. Recent research shows that Natural Killer Cells also play a role in the adaptive immune response.
    • Dendritic Cells and Gamma/Delta T Cells – These are the bridge between the innate and adaptive systems and their main role is antigen presentation. They harvest antigenic proteins from damaged pathogens and present them to T-cells, which allows them to find and attack the pathogens.
Immune system myths
Visual depiction of the innate immune system. Notice the complexity? There is no way to boost all of the individual parts.

Part 2. The adaptive immune systemThe dendritic cells, from the innate immune system, activate the body’s adaptive (or acquired) immune system. The adaptive immune system is composed of highly specialized, systemic cells and processes that eliminate or prevent pathogen growth.

In acquired immunity, pathogen-specific receptors are “acquired” during the lifetime of the organism (whereas in innate immunity, pathogen-specific receptors are already encoded in the germline). The acquired response is said to be “adaptive” because it prepares the body’s immune system for future pathogenic attacks. In some cases, the acquired immune response can be maladaptive when it results in autoimmunity.

Antibodies, produced by B-lymphocyte cells, are the main weapon of the body’s immune system to battle pathogens. It is a larger response than innate immunity and once sensitized to an antigen, the adaptive immune system often fights off diseases even before we can present with symptoms of a disease.

Immunizations introduce the pathogen’s antigen to the adaptive immune system so that it can form those pathogen-specific receptors and, thereby, are able to quickly and efficiently respond to an attack by a pathogen, before it harms the host.

There are three types of cells involved in the adaptive immune response:

  • T – Lymphocytes (also known as T-cell) – The main role of the cell is to recognize cells infected by viruses and trigger the apoptotic pathway that destroys the cell and its viral contamination. Since viruses only replicate inside cells by hijacking the cell’s manufacturing process, this apoptosis kills the virus (and the host cell) and phagocytes swoop in to consume the destroyed cell debris and digest the contents. The antigen of the viral cell is recognized by surface antibodies on the T-Lymphocyte, which activate it. There are also helper T-Cells whose role is control and organization of the apoptosis response to the infected cells.
  • B – Lymphocytes  The main role of these cells is to produce humoral (free floating) antibodies that recognize pathogens and mark them for destruction by other cells. This process occurs by activating the complement system and by causing the pathogen to become “sticky” but only with other pathogens. This causes them to clump together and make them easier to kill by T-cells.
  • Memory Cells – After an infection has passed (and most of the T-cells and B-cells have died), a few do remain in circulation to remember the antigens of the pathogens who attacked. In future infections, these are rapidly activated to produce a humoral response which quickly destroys any new infections even before they produce any symptoms. There are two types of these cells: Memory B cells, which, produce the antibodies that recognize the pathogens, and Memory T cells, which remember the viral antigens that infect cells.
There's no way to make this simple. It's complicated.
There’s no way to make this simple. It’s complicated.

And there’s actually more. In Infants, there is a version of the immune system called passive immunity. Certain classes of antibodies can cross the placental barrier and can be absorbed through milk particularly the colostrum (first milk). These give the newborn baby the same range of protection as the mother.

However, the baby’s immune system does not develop its own adaptive immune response from these antibodies, and eventually must be presented with one of the millions of antigens it inhales every day to form its own adaptive immune system.

So take a deep breath. That was a boatload of science.

The innate and adaptive immune systems are pretty freaking awesome, but it’s not perfect. Pathogens have evolved over a billion years or so in response to other organisms’ immune systems, so they have developed all kinds of tricks to avoid being massacred by the human immune system.

The influenza virus is one of the experts of quickly evolving to change itself almost annually to avoid the immune system. HPV (human papillomavirus) avoids the immune system by actually integrating itself into the human DNA.

So, we have an effective and highly aggressive immune system already. So obviously there are ways to boost this system. Right?

Immune system myths – any science?

I just described the awesome complexity of the immune system. There is a multitude of immune system related cells, each produced in different areas of the body, each with a different responsibility. Some of these cells produce literally millions of different antibodies, each with a separate responsibility to attack diseases.

The description I wrote above is difficult for anyone, even a trained immunologist, to understand completely. When someone talks about the immune system, I wonder if they understand that it’s so complicated that it could take years to understand just one component.

And is there any physiologically plausible method to boost or enhance all of this system or even a small part of it? In general, the immune system is an on/off type of network. It’s either working perfectly well, or it isn’t, and we know the precise conditions that might cause the immune system to start working less perfectly.

According to the Harvard Medical School; the University of Rochester Medical Centre; and Science-Based Medicine, we can conclude that:

  1. There are some chronic conditions, such as stress and malnutrition (I’m not talking about not enough oranges, but large, long-term calorie and micronutrient deficits), that can reduce the performance of your immune system.
  2. There are a few chronic diseases that can have an impact on the quality of the immune response, diabetes being one of the more prevalent, but there are many others.
  3. Some people are born with impaired immune systems. Some may acquire an immune deficiency as a result of certain diseases (HIV/AIDS being the most famous). Even some medical treatments, like chemotherapy or immunosuppressive therapies, can weaken or even destroy the immune system. One of the tropes of the immune system pseudoscience is that an infection weakens the immune system; in fact, the sick feeling you have during a cold or other diseases, can be a part of the immune response.
  4. Almost everyone has a perfect and highly effective immune system–there is no way to make it better.
  5. There is little evidence that a normally functioning immune system can be “boosted.” And by evidence, I mean high quality randomized clinical or epidemiological studies published in high-quality peer-reviewed journals.
  6. “Boosting” the immune system is probably not a good idea – see the next section.
  7. There are ways to prevent diseases like cancer. But it has nothing to do with boosting the immune system.

Too much boosting

On the other hand, if you really could boost your immune system, is that even a good idea? How can you even fine-tune a “boost” without figuring out the exact amount necessary to get the effect you want?

In fact, there are reasons why we shouldn’t have a too powerful immune system. For example, overactive immune systems are responsible for allergic conditions such as asthma and eczema. And there’s a type of runaway immune response known as a “cytokine storm” which may be responsible for the high mortality in severe flu pandemics.

Inflammation is normally a healthy response to injury or pathogen invasion, but in some autoimmune diseases, such as rheumatoid arthritis, it can be painful and debilitating.

In addition, an overactive immune system can become misdirected and start attacking the cells of the host body. This immune system error can cause autoimmune diseases such as arthritis and Type 1 diabetes.

So, no, it really is not a good idea to boost your immune system, even if you could (and you really can’t).

Vaccines boost the immune system

So what we need is a way of beating diseases at their own game. A way of acquiring immunity to diseases without the pathogen causing a disease. Let me think of a way, it’ll come to me.

That way is vaccination. Despite the complexity of the innate and adaptive immune systems, vaccinations are among the simplest medical procedures ever – we take known antigens and inject them into the body, but in a way that they cannot become infectious.

The body’s adaptive immune system recognizes these antigenic particles of the pathogen, and produce an immune response as if there were a real threat. Then the memory cells stick around to attack subsequent infections from that same pathogen. Every future infection your immune system stops actually increases the quality and speed of your immune response.

As long as we have been vaccinated, the adaptive immune system can respond quickly to a pathogen, prior to the pathogen having a long-lasting deleterious effect on the body or becoming infectious and spreading to others. No one makes the claim that vaccines are 100% effective, but as long as the vast majority of individuals are immune to a disease, it has a lower chance of spreading.

So there. That’s the one way, with strong scientific support, and we call it a vaccination.

TL;DR version

  • The immune system is an extremely complex interaction of organs, cells, proteins, other biochemicals, and tissues.
  • The immune system basically works well as a result of hundreds of millions of years of evolution. Only a chronic disease or malnutrition can make it work less than ideal.
  • No, we can’t boost the immune system with a handful of supplements or eating organic foods.
  • If you really could boost the immune system, it’s probably a bad idea to do so.
  • The one way we make the immune system work better is through the vaccination, based on evidence that vaccines make our immune systems think that it has fought off a disease when in reality it has not. Then it is ready to fight the disease when it does actually show up.
  • Just relax. Your immune system is so powerful, you really don’t have to worry about it. In almost every healthy individual, the immune system is running nearly perfect levels without you worrying about it.

Editor’s note: This article was originally published in September 2013. I have copyedited the article for clarity. Also, broken links were fixed, formatting was improved, and splines were reticulated. Yes, describing the immune system is difficult, and I have probably insulted real immunologists, who have 8-10 years of education and another 10-20 years of clinical experience. I have two years of graduate level classwork in immunology, and I am an amateur in the field. You will not become an expert on the immune system by spending an hour Googling stuff or reading this article. 

Note: I have, without any conscience, liberally stolen the idea for this article, and some of the supporting information from fellow blogger and Australian Graham Coghill of the most excellent blog, Science or Not.

Key citations:


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