How Stress Affects Your Immune System—Plus Ways to Keep Calm and Stay Healthy

How Stress Affects Your Immune System—Plus Ways to Keep Calm and Stay Healthy
How Stress Affects Your Immune System—Plus Ways to Keep Calm and Stay Healthy

Have you noticed that when you’re stressed, you often don’t feel your best? It’s no coincidence: Stress and the immune system are inextricably linked. Indeed, your mind and body are closely connected and in constant “conversation,” with your mental health able to influence your physical health.

In this article, we’ll explore the complex relationship between stress and immunity, as well as simple ways to keep calm and stay healthy.

But before we dive in, it’s important to know how the immune system works and to understand the stress response.

What Is the Immune System and How Does It Work?

Your immune system is a large network of organs, tissues, and cells that works to keep you healthy. It defends your body against potentially harmful substances known as antigens, which include germs such as bacteria and viruses, toxins, and even damaged cells.1

How? It mounts an immune response: Your immune system develops and deploys antibodies and cells to attack an antigen and keep it from causing harm. It also stores a memory of the antigen to recognize it in the future. That way when the antigen tries to invade your body again, if your immune system is working correctly, it can respond fast and efficiently, quickly sending out the right antibodies to protect you. This protection is called immunity.

There are three different types of immunity:

  • Innate immunity—protection you’re born with and your body’s first line of defense against antigens; this natural protection is provided by organs, tissues, and some cells
  • Active immunity (sometimes called adaptive or acquired immunity)—protection that develops after an infection or vaccine; you build up antibodies in response to the exposure, and the protection is typically long-lasting
  • Passive immunity—protection that occurs after you directly receive antibodies; in this case, your body does not make them itself, and this protection is usually short-lived

Unfortunately, the immune system doesn’t always function as it should. Certain conditions can impair immune function, as can some medications. Lack of sleep, poor diet, and other lifestyle choices as well as stress can all cause a weakened immune system, too. Much more on the latter in a minute.

Understanding the Stress Response

Stress Response Cycle

Although you may not immediately think of it as such, the stress response cycle is a good thing. Like the immune system, it is designed to protect you against outside threats.

Say you’re walking in the woods and have a chance meeting with a bear. You want the stress response—aka the fight-or-flight-response—to kick in!

Here’s how the cycle goes: When you encounter a stressor, your brain sounds the alarm throughout your body. This prompts your adrenal glands (part of your endocrine system) to release stress hormones, including adrenaline and cortisol, to help you flee to safety or fight back if needed. These hormones give you the boost of energy you need when threatened and alter bodily systems, including the immune system, in various ways to help you best survive or otherwise get through the stressful situation.2

Normally, once a threat has passed, these hormones return to their usual levels and your systems go back to their regular functioning. You stay well and the cycle is ready to begin again when called upon.

While you don’t likely regularly encounter bears in the woods, you do experience other stressful moments that can trigger fight-or-flight—from traffic to a difficult day at work, and the list goes on. Though our bodies don’t need to react to everyday, non-life-threatening situations in this way, they’re evolutionarily predisposed to.

That can be a problem. Let’s explore this more.

The Relationship Between Stress and the Immune System

Immune System

Though we now understand that stress and immunity are connected, this wasn’t always the case. In fact, for quite some time, it was commonly accepted that the brain and immune system were separate entities that never interacted, and that one’s psychological state couldn’t affect one’s physical well-being.

But pioneering research conducted in the 1980s and early 90s changed that way of thinking and provided concrete evidence of an intricate relationship between the two.

Noticing that animal studies had begun to link stress to infections, a psychologist and immunologist teamed up to study medical students over the course of a decade. They ultimately discovered that every year during their exam period, the students’ immunity decreased. Specifically, during this stressful time, they had fewer of the important immune cells that help fight infections, and the cells they did have weren’t in prime fighting shape.3

Since then, research into the relationship between stress and immune system function has exploded. Hundreds of studies have been conducted and confirmed stress’ ability to negatively impact the immune system. An entire field dedicated to investigating the link has been created: psychoneuroimmunology.4

The breadth of literature paints a picture of an incredibly complex relationship, describing multiple ways in which the brain and the immune system communicate. But if we go back to the overviews of the immune system and stress response cycle, we can begin to piece things together for a basic understanding. Their “conversation” is one of the main pathways that allows the stress in your mind to affect your body.

Stress’ impact on immunity has a lot to do with the hormones mentioned earlier, especially cortisol. Researchers have discovered that when the stress response is triggered, the burst of cortisol and other hormones initially mobilizes the immune system so that the body is prepared to handle injury or infection. This is beneficial when there really is a threat of physical harm and when the period of stress is short-lived; after the threat is gone, all bodily systems return to baseline.5

But when stress lasts for a significant period—from days to years—the body keeps pumping out stress hormones and the immune system stays in high gear. As time passes, the immune system becomes taxed rather than mobilized. The result is suppressed immune function and weakening of both innate and active immunity.

In today’s modern world, stressors are always present. When your immune system is continuously “switched on” from everyday stress, it can’t produce adequate amounts of or powerful enough immune cells that create antibodies and otherwise fight antigens, and thus it can’t protect you as it should.

Herbs and Tips for Mind–Body Wellness*

Holy Basil

Of course, when you don’t feel your best, it can add extra stress to your life. Not to mention, when you’re feeling off and stressed out, you may not get the rest you need—and lack of sleep can impact the immune system, too. In other words, there are many ways stress and immunity are connected, and it can be easy to get caught up in a vicious circle that leaves you depleted.

That’s why we recommend creating a mind–body wellness routine that includes herbal stress support and immune support—especially during challenging immune seasons.*

Add In Adaptogens & Other Stress-Supporting Herbs

When it comes to stress support, adaptogens deserve a place in the spotlight.* Adaptogenic herbs get their name from their ability to help you adapt to and find balance amidst life’s challenges.* They read your body’s needs in tense times and smooth out its stress response cycle so you can cope in a healthy way.*

For everyday support, our best-selling Adrenal Health® Daily Support formula in convenient capsules combines four superstar adaptogens—RhodiolaHoly Basil (pictured above), Ashwagandha, and Schisandra—to help stabilize the body and maintain well-being.*

When you need a little help finding a calm response to life’s trying moments, count on our award-winning Calm A.S.A.P.® formula, a blend of calming herbs including PassionflowerChamomile, and Vervain.*

Shop all our plant-powered stress-support supplements.*

Embrace Black Elderberry & Other Immune-Supporting Herbs

Black Elderberries have been used for centuries to support immune health.* These small, dark berries contain polyphenols, antioxidants that can support the immune system to help you stay healthy.*

Our Certified Organic Black Elderberry gummies are delicious and convenient—made from real fruit, without any added flavors, colors, or refined sugars. Adult Daily Gummies are designed for everyday, year-round immune support, while our Extra Strength Gummies offer extra support when you need it.*

We also offer Black Elderberry syrups, capsules, powders, and a tonic; browse all Elderberry products.  

When you need support at onset , turn to our Quick Defense® formula with Elderberry, Echinacea, and Andrographis.* These fact-acting capsules support your body’s natural defenses and can be used at home and on the go.*

Focus on Self-Care & Make Room for Relaxation

In addition to stress and immune supplements, it’s important to practice self-care in other ways as well. Stay active, get good rest, and enjoy a nutritious diet to stay feeling your best. Consider finding relaxation techniques that work for you and incorporate them into your routine—whether breathing exercises, visualization, or meditation.

For more ideas, check out these articles:



  1. “Immune System and Disorders,” MedlinePlus, accessed September 29, 2021,
  2. Mayo Clinic Staff, “Chronic Stress Puts Your Health at Risk,” Mayo Clinic,
  3. “Stress Weakens the Immune System,” American Psychological Association, February 23, 2006,
  4. Suzanne C. Segerstrom and Gregory E. Miller, “Psychological Stress and the Human Immune System: A Meta-Analytic Study of 30 Years of Inquiry,” Psychological Bulletin 130, no. 4 (2004): 601-630,
  5. Jennifer N. Morey et al. “Current Directions in Stress and Human Immune Function,” Current Opinion in Psychology 5 (October 2015): 13-17,