The Stress & Immune System Link: How Are They Connected?

Feb 18, 2022 Immune SystemStressWellblends 5 MIN

The Stress & Immune System Link: How Are They Connected?

Quick Health Scoop

  • Both acute and chronic stress can impact the body
  • Facing a perceived “danger” (stress) triggers the release of fight-or-flight stress hormones, including adrenaline, dopamine, cortisol, and norepinephrine
  • The link between stress and immunity is complex, but the effect of stress on immune system can be significant—especially when dealing with chronic stress
  • You can take steps to fortify your immune system

Most people face some stress on a regular basis. Acute (short-term) stress occurs when something temporarily upsets us—such as a student nervous about taking an exam or a commuter who just missed the train to work. Chronic (long-term) stress occurs when we deal with an upsetting situation for a long time, such as taking care of an ailing parent or living paycheck-to-paycheck for months or years. 

While stress can be tough to deal with anytime, the ongoing past few years have been especially tough for many. In fact, the American Psychological Association recently conducted a survey called “Stress in America.” The study found that, although general stress levels remained steady over recent years and most people maintain a positive outlook, about one-third feel overwhelmed with daily struggles. Moreover, roughly 32% of adults are sometimes so stressed that they struggle to make even simple decisions, such as what to eat or what to wear.[1]

All this might make you wonder about the link between stress and immune system. In particular, can stress weaken your immune system?

Let’s dig into what the research says about the link between stress and the immune system. 

How Does Stress Affect The Immune System?

First, it helps to understand how the body reacts to threats. When facing a perceived “danger,” the body naturally responds by sending signals from the brain throughout your nervous system. This triggers the release of “fight-or-flight” stress hormones called catecholamines, including adrenaline, dopamine, cortisol, and norepinephrine.[2,3] Once the threat passes, the hormone levels eventually return to normal, the heart rate and blood pressure eventually return to baseline levels, and other body systems resume their regular functioning.[4]

As mentioned above, not all stress is equal. Because acute stress starts and stops fairly quickly, it’s not likely to cause any major health problems. Our body naturally deals with it and then will return  to normal. 

However, chronic stress is another issue, as it can take its toll on your health. Does stress weaken your immune system? When stressors start, then continue without any end in sight, your body stays in a constant fight-or-flight mode. The body’s stress response system kicks in for the long-haul, and it overexposes the body to a steady stream of stress hormones, including cortisol. This can disrupt your body's regular functioning and affect virtually all of its systems—including the immune system.

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Can Stress Weaken Immune System

Yes, stress weakens the immune system. 

One of the primary ways immune cells work is that they move to the right parts of the body to protect against infections and pathogens in the body. 

Stress affects the immune system. Why is the immune system affected by stress? Studies show that nerve signals produced in response to stressors can stop immune cells from effectively doing their job. Stress hormones, including cortisol, when in excess or deficiency, can prevent the immune system’s ability to protect the body.[5] 

Furthermore, a meta-analysis of research showed that, for stress of any significant duration—even just a few days—all aspects of immunity worsened, which explains why chronic stress can ravage the immune system.[6] How does stress affect the body's ability to heal? The weakening effect of stress on your immune system means it makes it much harder for your body to heal itself. The same meta-analysis noted above also revealed that older people and those who are already sick are more likely to face stress-related immune changes.[6]

Why do we get sick after stress? Because stress puts your body’s immune system in a weakened state, you’re more likely to get sick during or after dealing with stressful situations. More specifically, why does stress make you more susceptible to respiratory infections and other health problems? Think of stress as a domino effect. Chronic stress raises the levels of catecholamine (stress hormones) and suppressor T cells. In turn, this suppresses the immune system, which increases the risk of viral infection.[7] 

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A variety of biological changes take place in the body when dealing with chronic stress. Chronic stress can also: [7,8]

  • lowers the body’s immune response 
  • releases histamine
  • alters insulin needs
  • alters the stomach’s acid concentration

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Besides stress, what challenges the immune system? Both controllable and uncontrollable factors can affect the immune system. Certain medications (such as chemotherapy or organ rejection medicines), infections (the flu and mononucleosis) and autoimmune conditions (severe combined immunodeficiency and HIV) can all weaken the immune system. Lifestyle factors such as alcohol use, smoking, and poor nutrition can also negatively impact the effectiveness of your immune system functioning.[9]

How Can I Support My Immune System? 

The good news: You can do a lot to manage stress and support your immune system! For starters, follow these guidelines:[4]

  • Eat a balanced, healthy diet
  • Exercise regularly
  • Get plenty of sleep
  • Maintain healthy relationships with open communication
  • Make time to enjoy hobbies
  • Practice relaxation techniques like breathing exercises, meditation, and yoga

The Bottom Line

Everyone deals with stress. But does stress affect the immune system? The impact of stress on the immune system varies depending on the type of stress you’re dealing with. Stress triggers the release of fight-or-flight stress hormones, including adrenaline, dopamine, cortisol, and norepinephrine. Occasional stress will likely not cause any serious health problems. But chronic stress can take a toll on both mental and physical health by overexposing the body to a steady stream of stress hormones, including cortisol. This can disrupt your body's regular functioning and can weaken the immune system. Fortunately, you can take steps to support your immune system, including eating healthy, getting adequate sleep, and exercising regularly.

Continue to check back on the Nature Made blog for the latest science-backed articles to help you take ownership of your health.

Learn More About Stress & Immune System:

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  • Follow @NatureMadeVitamins on Instagram for new product news, healthy lifestyle tips, and more.

    This information is for educational purposes only and is not intended to serve as medical advice or a recommendation for any specific product. Consult your healthcare provider for more information. 


    1. American Psychological Association. “Stress and decision-making...” October 26, 2021. Accessed on: December 28, 2021.
    2. Discover Magazine. “What Stress Does to the Immune System.” October 26, 2021. Accessed on: December 29, 2021.
    3. Medical News Today. “What are catecholamines, and what do they do?” July 24, 2020. Accessed on: January 3, 2022.
    4. Mayo Clinic. “Chronic stress puts your health at risk.” July 8, 2021. Accessed on: December 28, 2021.
    5. University of Melbourne. “How stress can stop immune cells in their tracks.” April 29, 2021. Accessed on: December 28, 2021.
    6. American Psychological Association. “Stress weakens the immune system.” February 23, 2006. Accessed on: December 29, 2021.
    7. The Malaysian Journal of Medical Sciences. “Life Event, Stress and Illness.” October 2008. Accessed on: January 3, 2022.
    8. Cleveland Clinic. “What Happens When Your Immune System Gets Stressed Out?” March 1, 2017. Accessed on: December 28, 2021.
    9. Johns Hopkins Medicine. “Disorders of the Immune System.” 2022. Accessed on: January 3, 2022.


    Lisa Beach

    NatureMade Contributor

    Lisa Beach is a seasoned journalist whose work has been published in The New York Times, Good Housekeeping, Eating Well, Parents, AARP’s Disrupt Aging, Optimum Wellness, and dozens more. She also writes for a variety of health/wellness-focused brands. Check out her writer’s website at

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    Lynn M. Laboranti, RD

    Science and Health Educator

    Lynn is a Registered Dietitian (R.D.) and is a member of the Medical and Scientific Communications team at Pharmavite. She has over 20 years of experience in integrative and functional nutrition and has given lectures to health professionals and consumers on nutrition, dietary supplements and related health issues. Lynn frequently conducts employee trainings on various nutrition topics in addition to educating retail partners on vitamins, minerals and supplements. Lynn has previous clinical dietitian expertise in both acute and long-term care, as well as nutrition counseling for weight management, diabetes, and sports nutrition. Lynn earned a bachelor’s of science in Nutrition with a minor in Kinesiology/Exercise Science from The Pennsylvania State University. She earned a M.S. degree in Human Nutrition from Marywood University in Scranton, Pennsylvania. Lynn is an active member of the Academy of Nutrition and Dietetics, Sports Cardiovascular and Wellness Nutritionists, Dietitians in Functional Medicine, and holds a certification in Integrative and Functional Nutrition through the Academy of Nutrition and Dietetics.

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