At its core, stress is simply the body’s physical, mental, or emotional reaction to change. Stress is not only a normal part of life, but a helpful tool. It is stress that helps us act safely in times of danger, motivates us to succeed, and alerts us to circumstances we should avoid. This is called eustress, or “good” stress.

Stress as most of us know it, however, doesn’t always seem so great. This is because we are experiencing small amounts of stress nearly constantly in our modern lives. Our bodies are responding and adapting without time for rest. We are left feeling tired, angry, and even sick.

Stress and the Immune System

The immune system responds to stress in different ways. Acute stress has been shown to increase the immune system’s response, providing a safety net in case we need extra help to fight infection or heal an injury[i]. But when stress becomes chronic, these physical and mental changes can cause damaging wear and tear on the immune system.

Stress Impairs the Immune Response

White blood cells are a key component of the body’s immune system. These cells are responsible for seeking out invaders, creating and releasing antibodies, and destroying pathogens. Studies show that stress, both acute and chronic, negatively impacts these fighting immune cells. T-cells, which work to destroy invading pathogens like bacteria and viruses, are suppressed during the chronic stress responsei. Natural killer cells also show reduced activity with psychological stress, which decreases our resilience against viruses and cancers[ii].

Additionally, stress throws off the body’s Type1 – Type 2 cytokine balance, increasing the inflammatory cytokines. This leads to inflammation and damages to immune cellsi.

Stress Increases Cortisol

When we are stressed, the adrenal glands release a hormone called cortisol. Cortisol helps the body respond when we need to act quickly, as with the “fight-or-flight” response. Issues arise when our stressors are minor and don’t require the body to respond (such as with traffic, a deadline, or social stress), yet cortisol is still released into the bloodstream.

Over time, a consistently high level of cortisol negatively impacts many body systems, including the immune system[iii]. Most notably, cortisol causes the release of inflammatory Type-2 cytokines which suppress and damage the white blood cellsi. Stress and high cortisol also correlate with poor sleep. Studies show that increased levels of cortisol often lead to reduced sleeping hours, interrupted sleep, and less time spent in restorative sleep[iv]. This restorative sleep is a necessary recharge for the immune system and without it, our immunity suffers.

Stress Impacts Habits

Stress may indirectly affect your immune system if you commonly resort to certain habits to cope with stress. For example, alcohol and cigarettes lower the immune responsivity[v]. Junk foods high in unhealthy fats and sugar increase inflammation and exhaust the immune system. Skipping exercise[vi] or missing out on sleep[vii] increases cortisol and thereby weakens the overall immune function. Managing stress can help us stay on track with healthier habits that work in favor of the immune system and prevent chronic disease.

Simple Stress-Relief Techniques

The research paints a clear picture: chronic stress can negatively affect our immunity. To help protect and strengthen the immune system, we can actively work to fight against stress. Here are a few simple habits that help to keep stress levels manageable while improving your immune health[viii]:

General Health Habits

  • Stick to a regular sleep habit and aim for 7-9 hours of quality sleep per night. This helps your immune system fully recharge.
  • Make 20-30 minutes of exercise a daily habit to improve hormone balance and relax the mind.
  • Eat an anti-inflammatory diet to provide healthy nutrients for your immune cells and keep inflammation low.

Managing Stress with Good Mental Health

Stress affects us both physically and emotionally, so maintaining good mental health is half the battle. We can best support the mind and body by adopting good mental health habits. Along with the general tips above, consider making these changes:

  • Take small breaks and schedule time-off throughout the year. Keeping a good work-life balance is key for keeping stress manageable.
  • Set realistic goals and healthy boundaries. It’s easy to burden ourselves with stress when our expectations are unrealistic. Instead, you can manage stress and achieve more by setting smaller and achievable goals. Similarly, relationships with friends, colleagues, or family can easily cause stress when there aren’t clear boundaries. Maintain healthy boundaries to reserve your energy.
  • Make time for mindfulness or meditation each day. Even a few minutes of quiet can help you regain your focus and attack problems with a clear head.
  • Reach out for social support. Spending quality time connecting with others helps us ease our minds and release the stressors of the day.
  • Spend time doing things that bring you joy. Be creative or take up a favorite hobby to give your mind a rush of feel-good hormones.
  • Unmanaged stress can quickly grow into issues like anxiety and depression. When stress consistently feels overwhelming, it is time to seek extra care. Meeting with a therapist can help you better understand your unique reaction to stress and learn coping techniques that support a healthy mindset. If you continue to struggle with stress, seek out medical help or talk to your doctor.

Reduce Stress to Stay Healthy

Research consistently shows that the chronic stress of our modern lives is a major health concern. Not only does stress reduce our quality of life, it also leads to a weakened immune system and a higher risk for chronic disease. Simple stress relieving habits help us live better and healthier.

 References:

[i] Dhabhar FS. Effects of stress on immune function: the good, the bad, and the beautiful . Immunol Res. 2014;58(2-3):193‐210. doi:10.1007/s12026-014-8517-0

[ii] Witek-Janusek, Linda et al. “Psychologic stress, reduced NK cell activity, and cytokine dysregulation in women experiencing diagnostic breast biopsy .” Psychoneuroendocrinology vol. 32,1 (2007): 22-35. doi:10.1016/j.psyneuen.2006.09.011

[iii] Segerstrom, Suzanne C, and Gregory E Miller. “Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry .” Psychological bulletin vol. 130,4 (2004): 601-30. doi:10.1037/0033-2909.130.4.601

[iv] Bradley Bush, ND, and Tori Hudson, ND. “The Role of Cortisol in Sleep.” Natural Medicine Journal. June 2010 Vol. 2 Issue 6

[v] Sarkar, Dipak et al. “Alcohol and the Immune System .” Alcohol Research : Current Reviews vol. 37,2 (2015): 153–155.

[vi]  Harvard HealthPublishing. “Exercising to Relax .”

[vii] Besedovsky, L., Lange, T. & Born, J. “Sleep and immune function.”  Pflugers Arch – Eur J Physiol 463, 121–137 (2012).

[viii] Cleveland Clinic. “Stress: 10 Ways to Reduce Stress .”