Hormones and Immunity, Part 2: Controlling the Curve
This is the second of a three-part post on hormones and immunity, and is part of our Superpower Series on defending ourselves in the COVID-19 era.
In Part 1 we talked about how getting a late night text is akin to being chased by a lion. Or rather, we talked about the adrenals and how Ancestral Us and Modern Us are often at odds when reacting to daily stressors. Let’s stay in that lane a bit longer.
Health Consequences of Stress Management
Cortisol Curve
Back to cortisol. In an emergency (actual or perceived), cortisol gives us energy, shunts blood and oxygen to our muscles for strength, raises blood sugar to feed our brain and muscles, sharpens mental focus, and performs an exhaustive list of other adaptive functions, which are about as long as we might imagine a congressional emergency preparedness plan to be. That all sounds great, so then why are people always talking about how bad cortisol is? Well, excessive cortisol can also contribute to high blood pressure, diabetes, heart disease, obesity, and, you guessed it: infection. So is cortisol good or bad? Well, in truth, it is neither. Like stress, there is a “Goldilocks” range of cortisol which promotes good health, and an extreme in either direction — too high or too low — causes imbalance.
Optimally, cortisol secretion follows a daily pattern which regulates our sleep/wake cycle, spiking in the morning when we wake up and declining throughout the day until we go to sleep. The curve should look like the green line in the graph below.
When we experience prolonged episodes of intense and repetitive life-threatening stress — especially when it’s unpredictable and interrupted by periods of listless inactivity and boredom — our cortisol secretion goes haywire. Sometimes there’s a heightened response, like the red line in the graph, with hyper-vigilance, anxiety, and tension — this usually occurs in the first few weeks or months of living in a high stress environment. At other times — typically after months or years — our bodies experience a sort of “boy who cried wolf” response.
But the adrenals get tired of the boy and his constant alarm bells and end up scaling back the usual cortisol secretion to only a minimal amount, almost as if they were saving it for the “real” emergency. This often looks like the yellow line in the graph above. Symptomatically, this flattened cortisol curve feels like difficulty getting out of bed in the morning, a midday doldrum followed by an evening rebound, and difficulty falling asleep at night. It's an extremely common pattern in patients I see (and most people I know, for that matter, at some point in their lives).
As mentioned earlier, when the endocrine system pushes the baseline pattern (or “laws”) to an extreme (either the red or the yellow line), it drags the immune and neurological systems with it. Immunologically, this causes a shift in the immune system’s Th1/ Th2 balance.
The Enforcers: Collaborating with Immune / Judicial Branch
The Immune System (“Judicial” Branch) is tasked with identifying anything that is not following the rules, usually involving cells or invaders that are intruding where they don’t belong. It is sometimes helpful to divide immune system activity into “Th1” or “Th2” dominance. Both these systems are required for optimal immune system function, and although they sometimes overlap in function, for simplification it is easiest to think of them as opposite ends of a see-saw.
The Th1 arm of the immune system fights bad guys that are inside our cells: viruses, certain bacteria, junked up and malfunctioning equipment (like cancer cells). It primarily uses cells like macrophages (literally, “big eaters”) which are like the Abrams tanks of the immune system and natural killer (NK) cells. These are some of the first responses to any infection, and they attack all foreign agents. Problems with Th1 immunity often lead to infections (low Th1) or systemic inflammation (high Th1). High cortisol, especially at night, suppresses Th1, which may leave you more susceptible to various infections, including viral ones.
Meanwhile, the Th2 arm of the immune system fights bad guys that are outside cells: certain bacteria, parasites, and toxic substances. It uses antibodies, mast cells (histamine-releasing cells), and eosinophils (a type of white blood cells). The Th2 response is a more targeted response, directed towards specific invaders, like a series of snipers. It's also often responsible for allergies and anaphylaxis. Both arms can be associated with autoimmune conditions.
One reason for the numerous immunologic problems on the rise in America may be a lack of balance and flexibility in the Th1/Th2 systems. This is of almost unimaginable significance, considering that immunologic (or “inflammatory”) disorders that have been increasing in the United States include:
allergies
Alzheimer’s and other forms of dementia
arthritis
autoimmune conditions, like Hashimoto’s Thyroiditis and Multiple Sclerosis
cancer (now estimated to affect nearly 40% of all Americans at some point in their lifetime)
diabetes
heart disease
inflammatory bowel disease
obesity
almost all psychiatric disorders (including ADD, autism, bipolar disorder, depression, and schizophrenia)
Given that a flattened diurnal cortisol curve is one of many factors that can contribute to rigidity (or fixed “dominance”) in the immune system, it is well worth addressing. The good news is that restoring your adrenal function to health is entirely under your control and does not require medications or expensive treatments. It does require some time, effort, and attention, and now that most of us have extra time on our hands during this COVID-19 disruption, it's the perfect time to improve adrenal health (and health in general)!
Self-Talk and the Ancestral Ledge
So how do we keep our adrenal glands from over- or under-reacting? This brings us back to stress and the mismatch between our Ancestral World, physiologic adaptations with our current, Modern World stresses.
In the previous case of our sweaty shirt board room debacle, our bodies have no model for the stress of power point presentations. Instead, our Ancestral stress response systems search the repertoire of common stresses and liken the situation to, let’s say, a long distance hunt with our tribesmen through the Savannah, responding in kind by keeping our adrenaline-pumped brain and muscles from overheating and dying. Our customary Modern response to the situation (artificial antiperspirants) may solve the obvious “problem,” but it ignores the other unseen effects of cortisol (eg, immune system imbalance) that are part of the response.
If we can recognize what our bodies are “thinking,” we could instead resolve the whole issue with a simple change of mindset. A few moments of meditation to “ground” ourselves in the present reality (we will probably score a few points and make a few mistakes — both of which no one will remember in a week: ie, no life-or-death consequences) may be all that is necessary to avert the unwanted outcome. The advantage to this is not that we have just saved a trip to the dry cleaner’s, but that we have used a simple but conscious technique to modulate our adrenal response, keeping ourselves on the green curve. We have redirected our ancestral adaptation to more appropriately match a modern stress.
Modulating adrenal function is one of the most important steps we can take to improve our immune system and our overall health. There are a million and one ways to rehabilitate our adrenal glands and numerous freely available resources online for more information. The most important factor to restore and preserve our adrenals is balance. If we strive for a pathway of moderate stress — somewhere between air traffic control and “finishing” Netflix — and learn to recognize and redirect (and not simply stifle) our bodies’ Ancestral reactions, the prize of health is ours for the taking. …
In Part 3 we’ll go yet further and talk about the affects that our good friend oxytocin has on immunity.
