What Most People Don't Know About Their Immune System

Understanding the difference between short-term defense and chronic activation.

Most people think about their immune system only when they get sick. A cold, an infection, a fever — and then it fades into the background again, doing its invisible work. But what if I told you that for millions of people, the immune system never truly goes back to rest? That it is quietly running in the background every single day, burning through your energy, aging your cells, and contributing to nearly every chronic disease we face today?

Your immune system does far more than protect you from illness — it influences your energy, mood, sleep, inflammation levels, healing, and even how you age over time. Most of us have unknowingly kept it stuck in a state it was never designed to sustain.

Before we dive in, if you missed last week’s issue about visceral fat and how it impacts your immune system you can find it here.

A healthy immune response is designed to act like a short-term emergency response team. When you get a cut, a bacterial infection, or a virus, your immune system quickly switches into attack mode. The process is rapid, coordinated, and — this is the important part — temporary.

Neutrophils — the fighter jets of white blood cells — are among the first responders. They rush to the site of injury or infection to destroy invaders and clean up damaged tissue before anything can take hold. They are aggressive, efficient, and fast.

At the same time, cytokines like IL-6 and TNF-alpha — inflammatory chemical messengers — are released to signal for backup and coordinate the full immune response. Think of them as the communication system for your immune army. Their job is to call in reinforcements, direct traffic, and accelerate the cleanup.

Deep inside your gut, your GALT — gut-associated lymphoid tissue — is quietly doing some of the most sophisticated immune work in your entire body. The GALT makes up nearly 70–80% of your entire immune system. It continuously scans for harmful pathogens, helps produce protective immune cells, and manufactures antibodies that protect your mucosal surfaces — your gut lining, lungs, and airways.

Once the threat is eliminated, something equally important happens: the off switch activates. Anti-inflammatory pathways engage, cortisol and immune signaling normalize, damaged tissue repairs, and your body returns to a balanced rest-and-repair state.

Inflammation was meant to be intense — but temporary. A brief, powerful burst of biological force that resolves and returns the body to balance.

Chronic low-grade inflammation is something entirely different — and far more dangerous in the long run.

In this state, the immune system never fully receives the signal that the danger has passed. It remains in a constant, simmering state of activation running below the surface every day.

Several modern lifestyle factors keep this alarm system perpetually switched on:

Chronic stress elevates cortisol continuously, which over time dysregulates immune signaling rather than resolving it. Poor sleep prevents the overnight immune reset your body requires to quiet inflammatory pathways. Ultra-processed foods deliver refined carbohydrates, seed oils, and chemical additives that trigger inflammatory cytokine production at every meal. Blood sugar spikes from high-glycemic foods activate the same inflammatory messengers — IL-6 and TNF-alpha — that are supposed to be reserved for genuine threats. Gut dysbiosis — an imbalance in the gut microbiome — disrupts the GALT's ability to distinguish friend from foe, keeping it in a state of low-level alert.

And then there is visceral fat — the fat stored around your organs. Unlike subcutaneous fat, visceral fat is metabolically active. It functions almost like its own organ, continuously releasing inflammatory cytokines like IL-6 and TNF-alpha directly into your bloodstream around the clock. There is no infection driving this signal. Just a relentless drip of inflammatory messengers with nowhere to go.

The gut makes this worse. Under chronic stress and inflammation, the gut lining can become more permeable — what researchers call increased intestinal permeability — allowing bacterial particles called LPS (lipopolysaccharides) to cross from the gut into the bloodstream. LPS is one of the most potent activators of the GALT and the broader immune system. When it leaks into circulation, it keeps your immune system on high alert even when no real threat is present.

Instead of neutrophils being deployed briefly and then standing down, your immune system remains in a slow, constant state of activation. The emergency response team never gets to go home.

Over time, this unrelenting immune signaling contributes to:

Your body was beautifully and intentionally designed to handle short bursts of inflammation. It was not designed to run an internal alarm system that never fully shuts off.

Your immune system does not need to be boosted — it needs to be balanced. The goal is not a hyperactive immune response, but a regulated one that activates when needed and quiets when the threat has passed. These six strategies work with your biology to help make that possible.

1. Eat an Anti-Inflammatory Diet

Every meal is either sending a pro-inflammatory or anti-inflammatory signal to your immune system. Removing ultra-processed foods, refined carbohydrates, and seed oils eliminates some of the loudest triggers. Adding in what your immune cells actually need — colorful vegetables, leafy greens, wild-caught fatty fish, grass-fed meat, fermented foods, and healthy fats like olive oil and avocado — gives your GALT and your gut microbiome the raw materials to regulate immune function properly. Fiber alone feeds the beneficial bacteria that produce short-chain fatty acids, which directly calm inflammatory signaling at the gut wall. Food is not just fuel — it is information your immune system reads at every single meal.

2. Walk Daily

Movement is one of the most underrated immune regulators available to you. Moderate, consistent movement like daily walking increases the circulation of immune cells throughout the body, reduces inflammatory cytokines over time, lowers cortisol, and improves lymphatic drainage, which is how your body clears out cellular waste and immune debris. Research shows that people who walk regularly have lower levels of systemic inflammation than sedentary individuals. The post-meal walk is one of the simplest and most impactful habits you can build.

3. Zinc

Zinc is one of the most critical minerals for immune function, and deficiency is far more common than most people realize — particularly in individuals with gut issues, since zinc requires a healthy gut lining for proper absorption. Zinc is essential for the development and activation of T-cells and natural killer cells, for regulating the inflammatory response, and for supporting the integrity of the gut barrier. Without adequate zinc, the immune system cannot mount an effective response — and cannot regulate inflammation properly once the response begins. Food sources include grass-fed beef, oysters, pumpkin seeds, and pasture-raised eggs. If supplementing, zinc picolinate or zinc bisglycinate are among the most bioavailable forms. Zinc should always be taken with food and balanced with copper if used long-term.

4. Vitamin C

Vitamin C is foundational to immune defense, and unlike most animals, humans cannot produce it on their own — we must get it consistently from food and supplementation. It supports the function of neutrophils (those first-responder white blood cells), stimulates the production and activity of lymphocytes, acts as a powerful antioxidant that protects immune cells from damage during an active response, and shortens the duration and severity of illness when levels are sufficient. Whole food sources like bell peppers, kiwi (eat the skin), citrus, and broccoli are excellent. For supplementation, buffered vitamin C or liposomal vitamin C are gentler on the digestive system and better absorbed than standard ascorbic acid.

5. Vitamin D3 with K2

Vitamin D is less a vitamin and more a hormone — and nearly every immune cell has a receptor for it. It plays a direct role in regulating both the innate and adaptive immune response, reducing the risk of overactivation (autoimmunity) while supporting the body's ability to fight infection. Low vitamin D is one of the most consistent findings in people with chronic inflammation, autoimmune conditions, and increased infection susceptibility. The K2 pairing matters: vitamin D drives calcium absorption, and K2 directs that calcium to bones and teeth rather than soft tissue and arteries. Always take D3 with K2, with a fatty meal for best absorption. Most adults benefit from 2,000 to 5,000 IU of D3 daily, but testing your levels is the best way to know your personal target.

6. Elderberry

Elderberry — Sambucus nigra — has been used medicinally for centuries and now has meaningful clinical research behind it. It is rich in anthocyanins, which are potent antioxidants with direct antiviral and anti-inflammatory properties. Research suggests elderberry can reduce the duration and severity of upper respiratory infections by inhibiting viral replication and supporting the immune response in the early stages of illness. It is best used at the onset of symptoms or as a seasonal support tool during higher-exposure months. Syrup, lozenges, and standardized extracts are all effective forms. Choose products with no added refined sugar, as sugar directly suppresses neutrophil function.

If you are looking for one supplement that does the heavy lifting for your immune system — this is it. CORE Immunity is one of the most comprehensive immune support formulas I have come across, and it is the one I recommend when someone wants a single, well-designed product that covers multiple bases simultaneously. It combines Vitamin C, Vitamin D3, Zinc, and Magnesium — the foundational immune nutrients — with powerful plant-based compounds including Quercetin, Bromelain, Black Cumin Seed (Nigella sativa), Resveratrol, and CoQ10. What I love about this formula is how intentionally these ingredients work together. Quercetin paired with Bromelain and Vitamin C significantly improves absorption. Quercetin combined with Zinc has documented antiviral properties. Nigella sativa alongside Vitamin D3 supports balanced immune response and healthy inflammation levels. And CoQ10 supports the cellular energy production that immune cells depend on to function at full capacity. It is not just an immune supplement — it also supports respiratory health, cardiovascular function, antioxidant protection, and cellular energy. One formula, covering ground that most people would need four or five separate supplements to address

Bonus: Prioritize Sleep and Manage Stress

No supplement stack will outperform consistent, quality sleep and a regulated nervous system. During deep sleep your body produces cytokines that fight infection and inflammation, consolidates immune memory from past exposures, and resets the HPA axis for the next day. Chronic poor sleep measurably suppresses immune function within days. Likewise, unmanaged chronic stress keeps cortisol elevated in ways that dysregulate immune signaling long-term. Sleep and stress management are immune interventions. Everything else on this list works better when these two foundations are in place.

The ancient writers understood something about the body that modern science is only beginning to quantify. Chronic emotional stress does not stay in the mind. It moves into the body. It alters cortisol, activates inflammation, and weakens the immune system's ability to return to rest.

We were not designed to carry anxiety as a permanent state. God knows the physical toll that chronic fear and stress place on a body He designed for peace. Philippians 4:7 promises "a peace that surpasses all understanding" that "will guard your hearts and your minds." That guarding is not just spiritual. It is physiological.

The healing journey is not just about what you eat or how you sleep. It includes learning to release what was never yours to carry — and trusting the God who designed your immune system to also be capable of quieting it.

"A cheerful heart is good medicine, but a crushed spirit dries up the bones." — Proverbs 17:22

Chronic inflammation is not your body working against you — it is your body responding to the inputs it has been given. The encouraging news is that small changes to those inputs can create powerful change over time. Start simple: add one anti-inflammatory food to your day and aim for at least seven hours of sleep each night. Then continue building from there. Small daily choices compound over time, and those little changes truly make all the difference.

Your body was designed to thrive. Sometimes it just needs the right building blocks to remember how.

With faith, science, and wellness,
Liz, The Wellness Nurse

Registered Nurse | Certified Mental Wellness Coach

P.S. — If you found this helpful, share it with someone who always seems to be getting sick, feeling run-down, or dealing with inflammation they can't explain.

P.P.S. — One of the questions I receive most often from this community is about supplements — which ones are actually worth it, which forms matter, what to take together, what to avoid, and how to know what your body specifically needs. I hear you, and I have been working on something for you. Keep an eye on your inbox — my Supplement Suggestion Guide is arriving soon, and it is going to answer a lot of questions. You are not going to want to miss it.

⚕️ Medical Disclaimer The content in The Wellness Nurse is for educational purposes only and is not intended as medical advice. Always consult your healthcare provider before making changes to your diet, supplement routine, or health practices. 

A note on transparency: some links in this newsletter are affiliate links, meaning I may receive a small commission if you choose to purchase through them — at no added cost to you. I share what I personally use, believe in, and would recommend to someone I care about. My goal is always your health and wellbeing.