Have you ever noticed that being run down and stressed can make you more susceptible to the latest virus? Although science has shown that stress and stress hormones can impair immune function, there is still much to learn about exactly how this happens. What is known is that when you experience any type of stress, your body has the same response as early humans did when they were faced with a physical attack ̶ it goes into a “fight or flight” reaction that affects every system in your body, including your immune system. Your brain triggers your adrenal glands (two little glands that sit on top of your kidneys) to secrete hormones to help you manage the stress. One type of adrenal hormone, catecholamines (such as adrenaline), is released quickly and acts fast. Catecholamines immediately increase your heart and breathing rate and shunt blood to your muscles to enable you to either fight or run. There is some evidence that they immediately boost certain aspects of front-line immune defense during a highly stressful experience (believed to help the body cope with injuries that might be sustained in an attack). Cortisol is a different type of adrenal hormone that has more sustained effects but acts more slowly. It changes your metabolism in ways that help you continue to deal with the stressor, such as creating sugar from other molecules to help maintain your energy. However, elevated cortisol seems to have a suppressive effect on some aspects of immune function over time.
Researchers exploring how stress hormones influence immunity wanted to look at the body’s reaction to a stressful event without the influence of the quick-acting catecholamines. They needed two groups of people: one that would have a normal response to a stressor, and one that would respond without the help of adrenaline and other catecholamines. To create a highly stressful situation, the researchers decided to have the subjects jump from a tall crane. 1 (I think this would do the trick!) They had 20 people bungee jump for the first time and recorded changes in their stress hormones and immune function before and after the leap. Half of the jumpers took a drug called a beta blocker prior to jumping. Beta blockers don’t interfere with the release of adrenal stress hormones, but they prevent the body from responding to some of the effects of catecholamines. The other group of 10 people jumped without taking the drug. Not surprisingly, catecholamine levels in both groups skyrocketed even before their feet left the platform. Cortisol increased during the jump.
What is surprising is that, although the beta blocker suppressed catecholamine effects in other areas (such as heart rate), the immune responses in both groups were the same. The function of white blood cells -one of the primary types of immune cells involved in fighting disease- was impaired, and overall front-line immunity was suppressed. These results are interesting because it shows that elevated cortisol, independent of the effects of catecholamine, can cause immediate and significant reductions in immune function.
Fortunately, it’s a piece of cake to avoid bungee jumping on a daily basis. Unfortunately, it is not as easy to dodge the multiple day-to-day stressors in a typical 21st century life and, as a result, many people have almost chronically elevated cortisol levels. Over time, this can undermine immune function and have potentially serious effects on your overall health. The good news is that you don’t necessarily have to eliminate all the stressors in your life to protect your immune function. Instead, you can do things that will support your immune system regardless of circumstances.
A different group of researchers studied the effects of a daily yoga practice on the immune system’s response to stress.2 Sixty college students were divided into two groups: one group practiced yogic postures (such as downward dog), controlled breathing and meditation for 35 minutes a day over a period of 12 weeks; the other group did not do any yogic postures, breathing or meditation.
At the beginning of the study, there was no significant difference between the two groups in measures of perceived stress, cortisol levels, heart rate, blood pressure, or levels of a component of the immune system called interferon gamma (IFNϒγ). IFNγ is crucial for immunity against viral and bacterial infections, and abnormal IFNγ activity is associated with inflammatory and autoimmune conditions. After 12 weeks, the two groups of students were tested again during the stress of academic exams. In the non-yoga group, levels of perceived stress, heart rate, cortisol levels, blood pressure, and breathing rate were all increased. Cortisol increased by almost 200%, and there was a significant decrease in IFNγ. In contrast, the yoga group had a lower level of perceived stress than the non-yoga group, and in one test of psychological stress, they showed a lower level of perceived stress than they had originally. Blood pressure did not rise, and heart rate and breathing rate actually decreased slightly from baseline values. Their cortisol did increase under the stress of exams, but only about half as much as the levels of the non-yoga group. The change in their IFNγ was insignificant. In other words, a daily practice of yoga helped temper not only the psychological experience of a stressful event, but the physiological response to stress, as well, including the suppressive effects of stress on immune function.
What this study shows is that even if you are under stress, you can diminish the negative effects on your body, including those on your immune system. In addition to doing the things you already know will help your body manage stress ̶ eating moderate, regular, nutrient dense meals; avoiding caffeine, sugar and other stimulants; getting enough restorative sleep; and using supplements to support your adrenals and immune system ̶ try incorporating yoga or another form of gentle, relaxing movement and breathing into your day. You have the power to make changes within a stress-filled life that will support your adrenal glands, your quality of life and your immune system. Oh, and if you decide to go bungee jumping, try doing a few downward dog postures first!
1. van Westerloo, DJ, et al. Acute stress elicited by bungee jumping suppresses human innate immunity. Mol Med. 2011;17(3-4):180-8.
2. Gopal, A, et al. Effect of yoga practices on immune responses in examination stress-a preliminary study. Int J Yoga. 2011;4(1):26-32.
About the Author
Dr. Lise Naugle is an associate of Dr. James L. Wilson. She assists healthcare professionals with clinical assessment and treatment protocols related to adrenal dysfunction and stress, and questions regarding the use of Doctor Wilson’s Original Formulations supplements. With eleven years in private practice and a focus on stress, adrenals, hormonal balance and mind-body connection, she offers both clinical astuteness and a wealth of practical knowledge. Dr. Naugle also maintains updated information about the latest scientific research on the hypothalamic-pituitary-adrenal axis function, endocrine balance and nutritional support for stress and develops educational materials about stress and health for clinicians and their patients.