Stress, Your Immune System, and Cancer: When chronic, high stress becomes a liability to your health.

Stress and Breast Cancer October_ Breast Cancer Awareness Month

There is never "just" one thing that causes cancer. It's a sum of many contributing parts: DNA, toxic load, microbes, cellular health, oxidative stress, the immune system, and...chronic, unregulated "stress". ( this list is not all inclusive)

When we talk about stress, most of us think of cortisol, tiredness, sleepless nights, or burnout. But the real cost of chronic stress runs much deeper.

The National Cancer Institute wrote an article, “Stress-Induced Immune Changes May Help Cancer Spread,” that sheds light on a possible mechanism: stress-driven immune dysregulation could facilitate disease progression in distant tissues. Cancer.gov

While the original focus of the study was on metastatic cancer, the underlying biology is relevant to all of us—especially high-achievers juggling performance, expectations, and perpetual responsibilities.

I've summarized the key pathways discussed in this study, why they matter, and what you can do to slow the damaging impacts that stress can have on our bodies.

Key Findings from the NCI Article (He et al. / NCI summary)

1. Glucocorticoids modulate neutrophils → increased NET formation

Naturally occurring glucocorticoids are cortisol, epinephrine, and norepinephrine which are made in the adrenal glands. They get secreted during times of perceived stress and when we wake up in the morning.

In the study, chronic exposure to stress hormones (glucocorticoids) caused neutrophils—an immune cell subtype—to produce excessive neutrophil extracellular traps (NETs), which are web-like structures composed of DNA and enzymes. In mice models, these NETs helped create a microenvironment in distant organs (e.g. lung) that favored metastatic cancer cell growth. Cancer.gov

1. Microenvironment remodeling, reduced immune surveillance

   Stress-exposed lungs, for example, showed fewer cancer-attacking T cells, and more fibronectin deposition (a scaffolding protein) that helped “anchor” metastatic cells. Cancer.gov

   
   

   In other words: stress doesn’t just act locally—it reshapes distant tissues to become more permissive for dysregulated cells.

   
   

2. Reversibility via NET inhibition

   Using a compound (DNase I) to block NET formation in the mice led to significantly fewer lung metastases in stressed animals. Cancer.gov

   
   

   This suggests that the stress → immune remodeling → disease progression pathway is not fixed—there is potential for interventions to reverse or mitigate the damage.

   
   

3. Human tumor gene expression parallels

When researchers looked at tumor samples from people with hormone receptor–positive breast cancer, they found gene expression patterns similar to those triggered by chronic stress in the mouse models.

Further, patients whose tumors exhibited those patterns had lower survival rates. Cancer.gov Note: this is associative, not causative.

Biological Threads That Bind: From Stress to Hormones, Inflammation, and Immune Disruption

To appreciate how stress becomes a systemic risk factor, let’s zoom out and connect the dots:

Biological Level	What Happens Under Chronic Stress	Why It Matters
Hormonal / Endocrine	Elevated glucocorticoids (e.g. cortisol), chronic HPA/HPG axis dysregulation	Hormonal imbalance, interference with estrogen/progesterone signaling, adrenal fatigue
Immune / Inflammatory	Overactivation of neutrophils, excessive NETs, lowered T cell surveillance, pro-inflammatory cytokines	Creates “sterile inflammation,” tissue remodeling, hindered immune vigilance
Tissue / Cellular Microenvironment	Increased fibronectin, extracellular matrix changes, oxidative stress, DNA damage	Alters cellular niches, makes tissues more vulnerable to aberrant cell growth
Systemic & Epigenetic	Altered gene expression patterns (mirroring stress signatures), mitochondrial dysfunction, epigenetic shifts	Increases susceptibility, weakens resilience over time

In essence: chronic stress damps your immune system, shifts your internal ecology toward inflammation, and subtly undermines cellular health—all of which set the stage for disease progression.

Why This Is Particularly Relevant for High-Achieving Women

• Constant “on” mode

  Many high performers thrive in high-pressure environments. Over time, the persistent rhythm of urgency, deadlines, and multitasking can bypass your body’s built-in checks and balances.

• Invisible load

  The emotional, neurological, and hormonal burden of sustained high expectations often goes overlooked until downstream symptoms (fatigue, brain fog, hormonal irregularities) emerge.

• Hormonal sensitivity

  Women are especially susceptible to disruptions in the HPA (stress) – HPG (reproductive) axis.

  Chronic stress can ripple into PMS, menstrual irregularities, fertility challenges, and challenging menopausal transitions.

• Hidden inflammation

  Symptoms like stubborn weight gain, joint pain, mood dysregulation, or recurring infections often mask underlying inflammatory dysregulation—something chronic stress fosters.

  
  

Actionable Strategies to Interrupt the Cascade

You don’t have to wait until symptoms appear. Here are evidence-informed strategies to interrupt or reverse this stress-inflammation cascade:

1. Cultivate deep recovery practices

   • Intentional breathwork, HRV (heart rate variability) biofeedback, meditation

   • Cold exposure, sauna, parasympathetic activation.

     These support autonomic balance and blunt overactivation of stress hormone signaling.

2. Optimize sleep and circadian alignment

   Deep, restorative sleep is when immune surveillance and cellular repair happen at scale. Improving sleep quality is non-negotiable.

3. Nourish anti-inflammatory terrain

   • Emphasize omega-3s, polyphenols, micronutrients

   • Minimize ultra-processed foods, sugar spiking, inflammatory fats

   • Support antioxidant systems (glutathione, NAD+, CoQ10, etc.)

4. Support immune regulation

   • Probiotic / microbiome support

   • Low-dose botanical modulators (e.g. adaptogens) under professional guidance

   • Nutrients that modulate neutrophil overactivation (under supervision)

5. Stress awareness & cognitive reframing

   • Journaling, boundary setting, therapy or coaching

   • Psychological resilience techniques to detect stress before it becomes chronic

6. Periodic detox & system resets

   • Gentle fasting, detox modalities, targeted movement protocols

   • Strategic rest periods, mini “digital sabbaths,” off-grid time

     
     

A Note of Caution, Context, & Disclaimer

• The NCI article’s findings arise from animal models, and though promising, have not yet been conclusively validated in human interventional trials. Cancer.gov

• Human tumor correlations are associative, not definitive proof of cause-and-effect. Cancer.gov

• Synthetic glucocorticoids (e.g. dexamethasone) used during cancer treatment are not the same as long-term exposures modeled in the research; dosage, timing, and duration matter.

• Also- synthetic "stress hormones" were being used. That means that not all stress is created equal and the amount of "cortisol" your body makes during a high stress moment may not be near the same as the dosage these mice were getting.

  
  

Bottom line: This article does not "prove" or definitively state that all stress or stress in general causes cancer or metastatic cancer.

That being said, it does highlight that stress biology matters. The micro-changes may be silent, but over years they accumulate.

Final Thoughts

Stress isn’t merely a mental or emotional challenge—it is a systemic biological load. When unchecked, that load reshapes your hormones, rewires your immune system, and sets the stage for low-grade inflammation and cellular vulnerability. The NCI article underscores that what we often discount as “just stress” can ripple into deeper territories.

For women who push hard, do more, and expect greatness of themselves: what if your greatest act of leadership is mastering your stress—not just in moments of crisis, but as an ongoing stewardship of your body’s terrain?

If you want a personalized guide rooted in both clinical science and holistic wisdom—one that helps you interrupt the cascade of stress before symptoms emerge—my Get Your Spark Back program is built for exactly that.

Happy to help when you're ready. Schedule your free Strategy Call today to learn more about how Dr. Lexi can help.

In good health,

Dr. Lexi

Get Your Spark Back