Stress is so pervasive that you might have a hard time finding an adult who doesn’t admit to feeling stressed. In 2017, Gallup reported that 79% of Americans sometimes or frequently felt stressed during their day.1 The global pandemic of 2020 and widespread demonstrations about racial and policing issues in the U.S. have no doubt contributed to even higher levels of stress among people around the world.
Our worldwide stress epidemic has dire health consequences, particularly because stress wreaks havoc on the human immune system. In the midst of the Covid-19 outbreak, a properly functioning immune system is more important than ever. How exactly does stress decrease immune response, and what can we do about it?
Three Types of Stressors and Their Different Effects
Hundreds of scientific research studies have identified a wide range of immune system responses to stressors. Compiling these and studying their findings, researchers learned that different kinds of stressors provoke different reactions in the body.2 Those types are acute stressors, stressful event sequences, and chronic stress.
An acute stressor is an incident of short duration that causes increased anxiety. If you’ve ever taken a test, given a speech, or found yourself stuck in traffic on the way to an important meeting, you’ve probably noticed physical signs of stress such as increased heart rate and jitters. These are signs of your body preparing for flight or fight because of a perceived danger. Acute stress causes your immune system to fire up “natural immunity” by marshalling natural killer cells and lymphocytes to fight off infection and speed wound healing in case you’re injured.
Thankfully, the modern-day acute stressors most of us face don’t result in physical injuries. As the situation passes, the immune system should quickly back down from high alert. A problem can occur when, for various reasons, your body gets “stuck” in this fight or flight state even after the immediate threat subsides. Inflammation is part of this immune response, and if the response doesn’t shut down, it can produce chronic inflammation.
Stressful life sequences include bereavement and trauma. These events produce different immune responses than acute stressors do. Losing a loved one causes a drop in natural killer cells’ ability to fight off the “bad guys” that find their way into the body, which could cause bereaved spouses to come down with whatever’s going around. People who live through natural disasters seem to experience a drop in immune response related to lymphocyte function.
Chronic stressors include caring for an aging spouse or parent, having a disability, and losing a home or job. Any change in one’s identity that makes the person feel less in control of or less hopeful about the future can cause this type of chronic stress. During the first three months of the Covid-19 outbreak in the U.S., unemployment rates rose more than they did over the entire Great Recession of 2007 – 2009, rivaling levels of unemployment during the Great Depression.3 Those who found themselves without work or worried about losing their jobs experienced this type of chronic stress, which seriously impacts the immune system. In fact, chronic stress has negative effects on nearly all the different ways that researchers measure immune system function.
Some People Are More Susceptible to Stress
Obviously, not everyone reacts to stress the same way. Some people seem to have much more resilience, and their immune systems don’t necessarily take a major hit even when faced with long-term stressors. One of the most important factors that influences whether stress reduces immune function is exposure to early life stress such as maltreatment, poverty, and even bullying.4 One study showed that five-year-olds living in families with high levels of psychological stress showed immune responses that are associated with autoimmune diseases such as Type 1 diabetes.5 In another study, younger adults who were victims of repeated childhood sexual abuse or physical abuse that began in their preschool years had greater levels of Epstein-Barr Virus antibodies, showing that their immune systems were unable to keep the latent virus in check.6 Stressful early life experiences can result in long-term suppression of healthy immune responses.
As people age, their immune systems become less reliable because their bodies become less successful at shutting down cortisol when they’re faced with stressful situations. Through a chain reaction, chronically high levels of cortisol increase inflammation and compromise normal immune responses. Often older people find themselves in the role of caregiver for a relative or spouse, and the caregiving role is associated with various markers of reduced immune function. Chronic stress results in shortened telomeres, a measure of biological age. So taking steps to minimize the effects of stress can help keep you younger than your years.
Optimize Immune Function by Managing Stress
Although most of us can’t eliminate stress or even avoid most of the stressors in our lives, studies have shown that optimism and coping with stress moderates the negative immunological responses. On the other hand, stewing over a stressful situation has its own ill effects. People who acknowledged having intrusive thoughts about the stressors in their lives showed reduced function of natural killer cells.
Here are some tools you can use to dismantle stressors and construct a healthier immune response to difficult situations.
- Develop healthy sleep habits. Although this may be easier said than done since 42% of people report that stress keeps them up at night,7 it can reap big rewards. Sleep loss itself may be responsible for some reduced immune system function. Create and follow a routine for getting to bed earlier and in a calmer state.
- Expect the best. An optimistic outlook has been associated with decreased immune responses despite chronic stress.
- Don’t stuff your feelings. Repressing emotions as a way to cope with the tough things in your life can actually make the negative effects of stress on your immune system worse.
- If possible, get a pet. Most pet owners report that their pets reduce their anxiety, and just ten minutes of petting a dog or cat has been shown to reduce levels of cortisol, a stress-related hormone, in the blood.8
- Engage in moderate exercise regularly. While intense workouts can cause immune system markers to drop, moderate exercise has positive immune system effects. And moderate exercise reduces the impact of aging on the immune system.
- Choose healthful foods. Although it’s tempting to load up on sugar or other “comfort foods” when you feel stressed, eating well makes you feel better so you can respond to life’s challenges.
- Laugh out loud. Some research has been able to document that people who watched a humorous video and laughed out loud had increased levels of natural killer cells in their blood.9 Most people know intuitively that a good belly laugh works wonders and can improve your outlook on life.
- Don’t go it alone. Dozens of scientific studies support another intuitive way to reduce stress, namely, by strong relationships with others. Having a supportive social network not only increases your happiness, but it may also reduce your risk of disease and increase your life span.10
- Find the right supplement. Many people find it easier to manage stress and keep on an even keel emotionally when they take targeted nutraceuticals.
- Pray. If you’re a person of faith, take advantage of the health benefits of prayer. Prayer is the single most widely practiced complementary medicine technique—about 90% of people who have a serious illness turn to prayer. For many, prayer creates what researchers call a “relaxation response” that lowers blood pressure and other markers of stress.11
- Make a difference. Find a cause that adds meaning and purpose to your life and pursue it. Senior citizens who engaged in volunteer teaching programs at local schools experienced significant health benefits.12 Giving of yourself makes you happier and helps others at the same time.
We invite you to keep following GWL for further nutritional and botanical strategies to help you cope with stress.
1Gallup, “Eight in Ten Americans Afflicted by Stress,” Dec. 20, 2017.
2 Segerstrom SC, Miller GE. Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry. Psychol Bull. 2004;130(4):601-630. doi:10.1037/0033-2909.130.4.601.
3 Kochar R. Unemployment rose higher in three months of COVID-19 than it did in two years of the Great Recession. Pew Research Center, June 11, 2020.
4 Morey JN, Boggero IA, Scott AB, Segerstrom SC. Current Directions in Stress and Human Immune Function. Curr Opin Psychol. 2015;5:13-17. doi:10.1016/j.copsyc.2015.03.007.
5 Carlsson E, Frostell A, Ludvigsson J, Faresjö M. Psychological stress in children may alter the immune response. J Immunol. 2014;192(5):2071-2081. doi:10.4049/jimmunol.1301713.
6Slopen N, McLaughlin KA, Dunn EC, Koenen KC. Brain Behav Immun. 2013 Feb; 28:63-71.
7 American Psychological Association Stress in America Report, 2013.
8 Pendry P, Vandagriff JL. Animal Visitation Program (AVP) reduces cortisol levels of University students: A randomized controlled trial. AERA Open, 2019; 5 (2): 233285841985259 DOI: 10.1177/2332858419852592
9 Bennett MP, Lengacher C. Humor and Laughter May Influence Health IV. Humor and Immune Function. Evid Based Complement Alternat Med. 2009;6(2):159-164. doi:10.1093/ecam/nem149
10 The health benefits of strong relationships. Harvard Health Newsletter, Aug 6, 2019.
11 Prayer. Earl E. Bakken Center for Spirituality and Healing. University of Minnesota, 2016.
12 McEwen BS, Gianaros PJ. Stress- and Allostasis-Induced Brain Plasticity. Annual Review of Medicine 2011;62:1:431-445