The immune system is a marvel of evolution.
At its simplest, the system — which includes various organs, proteins, chemicals, and white blood cells — recognizes foreign invaders like bacteria, viruses, fungi, and parasites, and tries to destroy them.
Those invaders — collectively called pathogens — can cause disease, infection, and other potentially dangerous changes in our bodies. The immune system will also target abnormal tissue and cells such as cancer that originate from within.
In order to keep us healthy and functioning properly, it must identify those pathogens and irregular cells quickly, then mobilize an attack to eliminate them. Overall, it’s an effective defense protocol.
The Immune System: A Crash Course
You could study the immune system for years and still not understand it all. In fact, it’s so complex and nuanced that it has an entire branch of biology called immunology devoted to it.
The brain, skin, lymph nodes, spleen, thymus, tonsils, adenoids, stomach, bowel, mucous membranes, bone marrow, and more all play a part in protecting us.
And white blood cells? Think of them as your infantry. They are your army ready to march into battle on your behalf. Some white blood cells circulate in your bloodstream while others reside in various tissues until needed.
There are several types of white blood cells, including:
- Phagocytes: attack, envelop, and “eat” foreign invaders; includes neutrophils (destroy bacteria and fungi), eosinophils (attack parasites and cancer cells), and macrophages (scavenger cells circulating in the body)
- Lymphocytes: help to both destroy and remember foreign invaders; includes B-cells (identify targets and call in reinforcements), T-cells (the foot soldiers), and “natural killer” (NK) cells
When the body identifies something foreign, the immune system jumps into action.
The Innate Immune System
This system works to protect us from all pathogens and invaders.
The skin is the first line of defense, providing a physical barrier. Mucous membranes, saliva, tears, and other secretions provide additional protection in any opening.
If something makes it past that first line, and the body detects an invader, the innate immune system will attempt to destroy it with phagocytes, NK cells, and possibly a fever.
This is a nonspecific response.
The Adaptive (or Acquired) Immune System
Any pathogen that survives the nonspecific response will grab the attention of the adaptive immune system.
Pathogens carry a unique antigen found on its surface. B-cells will identify the antigen and produce a special protein called an antibody that locks onto it. The antibody acts as a spotlight and alarm that summons T-cells to destroy the antigen.
Antibodies can also activate complement — a group of proteins that help kill bacteria, viruses, or infected cells — and neutralize toxins. They can remain in the body, allowing the adaptive immune system to “remember” specific pathogens for a faster and more efficient attack next time.
This is a specific response.
And that’s the immune system in a nutshell, your body’s defense against invaders.
But to limit it to “just” a defense system is to do it a disservice. Recent studies are revealing just how interconnected it is with the rest of the body.
Nurosene CIO and founder Dan Gallucci prefers to define it as such:
“The immune system is a highly evolved communication system that dynamically processes information from both its internal and external environments and then mediates its function accordingly.”
A communication system instead of just a self-defense one. Our understanding is changing.
Keeping Your Immune System Strong
A healthy lifestyle is key, and that includes:
- Regular exercise
- A healthy diet
- Quality sleep
- Alcohol in moderation, if at all
- No smoking
- A healthy weight
- Doctor-recommended vaccines and booster shots
You’ve probably also heard how detrimental stress can be to your immune system. And while that is generally true, our understanding of the relationship between the two is also changing.
Stress and Immunity
Stress can lead to a long list of conditions like depression, diabetes, high blood pressure, heart disease, and more.
That’s true. For chronic stress. Long-term and unchecked.
That said, we are starting to realize that some stress — acute stress — can actually be beneficial to us.
The Difference Between Acute and Chronic Stress
Simply put, most of us are stressed.
Stressed about money, work, our health, the future, the pandemic, climate change, family, and much, much more.
It’s relatively low-key, but long-term. It’s so broad that it doesn’t have one specific thing that we’re worried about, so there’s no end to it. No “thing” to get passed which allows us to relax.
That’s chronic stress, and it puts a massive strain on our physical and mental health, including our immune system. We are less ready and able to deal with whatever life throws at us. We all need to take steps to reduce our chronic stress levels.
The Nuro app, for example, has several activities tailor-made for that purpose, including gaze stabilization, brain adaptability, journaling, the 2-minute reset, and music mornings.
Acute stress, on the other hand, is short-lived and specific. It’s a direct response to a dangerous threat or situation. It’s our “fight-or-flight” reaction, and our immune responsiveness is actually heightened by it according to recent research. This mobilization of resources can last anywhere from a few minutes to a few hours, and it stimulates — rather than suppresses — immune activity.
Our brain registers a threat — perceived or real — and tells the immune system to get ready. Our bodies are then primed to fight or flee, and deal with any potential injuries resulting from either action. It’s preparation rather than response, and just one example of our immune system communicating in a way we never knew existed until recently.
When experiencing the fight-or-flight response, the body releases stress hormones such as norepinephrine, cortisol, and epinephrine. They help improve focus and concentration, stimulate blood flow to our muscles, and increase blood sugar levels to provide us with the required energy.
But we now know that’s not all they’re doing. Those three stress hormones mobilize the immune cells — both phagocytes and lymphocytes — the same way a foreign pathogen would do. It’s a call to battle before the battle takes place.
Acute stress can improve our immunity. It can enhance our protective response before we need it. Our immune system is not simply a reaction. Or just defense. It’s part of the chain-of-command.
And that’s an incredible revelation with amazing potential going forward.