Stress and Anxiety: The Double Agents of the Immune System

Everyone loves a superhero story, and COVID-19 has supplied plenty of them. The nurse pressing on during her 10th straight 12-hour day. The chef who has to scramble and cook up a new plan to keep the restaurant open that he started years ago. The fast food worker barely able to make ends meet, who went from a minimum-wage political scapegoat to an essential-working icon of the times, mentioned in the same breath as doctors and scientists.

But the making of these heroes comes at a cost. The untold tale is the stark toll that COVID-19 has exacted on the world’s psychological makeup. The pandemic has created swaths of uncertainty and financial instability, and with them, an abiding sense of fear and loss. It has put on hold the ability to engage in physical expressions of love and care with others outside of home. A casualty of this upheaval is the emotional balance that many people had come to enjoy from a brimming economy and a stable (if polarized) political world. Now, citizens everywhere must contend with some of the real-world emotional effects of its fractured economic and health care environments: stress, anxiety, panic, loneliness and despair.

The constant barrage of emotions like fear, guilt, sadness and anger can be difficult to navigate even in the most normal of times, let alone during a once-in-a-century plague. It is a cruel irony that these feelings weaken the immune system responsible for mounting a defense against the disease that has caused them. Let’s take a detailed look at the potential impact of these powerful emotions on your immune system’s ability to protect your body.

Immune System Basics

Before understanding the consequences of stressful emotions, it’s important to understand the fundamental aspects of the immune system. The immune system is your body’s military, with roles for defense and for internal repair. It has its own command structure and even its own hierarchy that oversees its daily operations. The immune system has complex weaponry and all sorts of styles, tactics, special ops and intelligence gathering. But it ultimately takes its marching orders from the commander-in-chief: the brain.

The immune system has a team of rangers (called antigen presenting cells) whose job is to obtain reconnaissance on any foreign invaders — viruses, bacteria, toxins, cells that aren’t yours — and neutralize them when they can. Those rangers present the recon to their commanding officers, called B cells, who design specialized, targeted, anti-invader weapons called antibodies. If the commanding officers see a big enough threat, they communicate with central command using two-way radio signals called cytokines. That central command is made up of lieutenants and generals called T cells, who make sure there’s no “friendly fire” or “collateral damage.” If the threat is a big one, those T cells use the same two-way radio signaling with cytokines to oversee mass production of precision, high-caliber antibodies and to communicate with the commander-in-chief that the military will need more resources. Together, this process is called the inflammatory response:

inflammatory responseAnd you thought your work flow chart was complex (courtesy: Christian Jacob)

Governed by Emotion

Emotions like anxiety, panic and stress introduce a lot of radio noise into that cytokine signaling system, making the whole immune system less effective. But this is done for a good reason. These feelings are essential to the well-being of any animal by giving them healthy doses of fear, and they make their presence known to the body by increasing a hormone called cortisol in the brain and bloodstream. If the immune system is the military, then cortisol is like a military spending freeze order from Congress or Parliament. Why? Cortisol is a signal to the body to activate the sympathetic nervous system, known commonly as “fight-or-flight” mode. Fight-or-flight means do-or-die for an animal’s survival, so all possible resources are diverted toward what will keep an animal alive. And just like in a government, there are only so many resources to go around; immunity has to take a back seat to the perceived immediate danger signaled by fear and stress. You’re vulnerable to disease for a bit, yes, but right now, says your brain, you’re more vulnerable to becoming some other animal’s dinner.

Fight or flightCan I call you back? I’m in the middle of something. (Courtesy: BBC)

In the short term, this system usually works great. Once the immediate threat has subsided, the body’s “military spending” on the immune system resumes, and it functions normally. But if stress and anxiety last for a long time, the body is constantly in fight-or-flight mode. The body’s normal resource allotment for the immune system is never restored, and thus there are fewer troops to fight viruses, bacteria and other threats. You’re now more susceptible to infection, and to worse consequences once infection takes place.

In Sickness and in Health

It gets worse from there. For the immune system, health and disease are like peacetime and wartime, and its defense and repair roles change according to the state of the body. During non-invasion times, the immune system engages in a constant flow of infrastructure projects: replace this tissue, dam up that bleeding vessel, clear out these old cells, eliminate these tumor cells, and so on. During times of constant anxiety and stress, your immune system can’t perform these tasks, so you’re left to function with old, damaged or inefficient parts. Ever notice how much less productive you are when you’re anxious, or how easily run down you get when you’ve been stressed? This is one major reason why.

Starved for Attention

With that context, it’s hard to imagine a better time for a study on the effects of stress or loneliness. Today’s Serendipity AwardTM co-winner is a group of researchers at the Massachusetts Institute of Technology (MIT). On March 26, two weeks after COVID-19 was declared a pandemic by the World Health Organization and stay-at-home orders were largely underway, MIT scientists released a preliminary report which showed that loneliness caused many of the same neurological manifestations as physical hunger.

And what might be the body’s appetite suppressant while during its lonely search for emotional nourishment? You guessed it: the sympathetic nervous system, putting the immune system at further disadvantage the longer the fight-or-flight mechanism is active — and this time without adequate resources for either system.

The Cure for What Ails You

So how do you resolve such a dilemma? While there’s little specific data as of May 2020 on emotional healing during the COVID-19 pandemic, previous psychology research offers helpful suggestions.The benefits of sleep and regular exercise like walking and biking have been shown to counteract some of the destructive force of stress, and they support immunity. Getting sleep and exercise requires the establishment and the maintenance of healthy routines, which isn’t an easy task as you adjust to your new COVID-19 reality. Maintaining a positive outlook, which can be difficult in a time when bleak news is abundant, can reduce some of the immune system’s tendency to overreact.

Meditation is a staple of stress reduction, but when you’re anxious, meditation doesn’t come easily. The good news is that the more you try to meditate, the better you tend to get at it, and the better you get at it, the more health benefits it confers.

Some supplements have stress relieving properties. Valerian root has evidence for its ability to reduce anxiety and promote sleep. Lemon balm has been used as a natural sleep aid for centuries. Other supplements are potent immune boosters, including the familiar staples of vitamins C and D. And here’s today’s other Serendipity AwardTM co-winner: A preliminary study just released from Indonesia looked back at 780 COVID-19 patients, and controlled for age, male sex and the presence of other disease, which all tend to predict worse outcomes. But even with those factors accounted for, people with COVID-19 and normal vitamin D levels (above 30 ng/ml) died 4% of the time, those with vitamin D insufficiency (20-29 ng/ml) died 88% (!) of the time and those with vitamin D deficiency (below 20 ng/ml) died 99% (!!) of the time. Two words of caution do apply, in that “preliminary” means the study still needs to be reviewed by experts, and that correlation doesn’t mean causation. However, such results certainly support the use of vitamin D in an experimental trial as a potentially helpful treatment for COVID-19.

It took a few amino acids on one spike of a virus about a millionth of a meter long (plus one pangolin) to upend the world and create pain previously unknown to current generations. But by the same token, little changes on the human end may be able to create the internal structures and routines that forge a path back to emotional stability. The mundane behaviors of getting proper rest and meditation may be a saving grace from even worse consequences. The ability to tend to the world’s collective mental health is likely to have an outsized influence on the trajectory of the current situation.


Author: L. Joby Morrow, M.D.

Dr. Morrow is a medical writer, former addiction medicine physician (with 7 years of his own sobriety), psychiatrist, and primary care physician.


If you would like to naturally support your mood, you may be interested in our mood boosting supplement, Zen1.

Alternatively, if you would like something to promote relaxation and restful sleep, you may be interested in Lemon-Aid 714. It contains two of the ingredients mentioned in this article, among others.

In the coming weeks we will also be releasing a powerful immune support supplement called Invictimune. The first batch will likely sell out fast, so subscribe to our email list if you would like to be the first to know ahead of the launch date.


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    1 comment

    • I couldnt agree more.

      Shana Lucero

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