Effects of Stress on the Immune System

Instructor: Lisa Roundy

Lisa has taught at all levels from kindergarten to college and has a master's degree in human relations.

Stress has an impact on our health through its effects on our immune system. Learn how our immune system is affected by stress, and what we can do to combat those effects.

Stress, Good and Bad

Imagine you come home from work and can't get the image of your boss yelling at you out of your mind. Maybe you are worried that your roommate is going to start a fight again. You feel tense, irritable, and tired. This is an example of the negative image we have of stress, a state of physical and mental tension caused by our problems.

This image provides a stereotypical view of stress in our society.

However, stress isn't always a bad thing. Feeling stressed can sometimes increase our alertness and energy, providing us with a performance boost. Let's call this good stress. Good stress is a survival response that occurs when we perceive a threat to our survival. At one time, it might have given humans that extra burst of energy to climb fast enough to avoid a bear attack; but it is more likely today that it allows you to run away really fast when you see a giant spider, or keeps you alert for your big math test.

The type of stress that is harmful to us is chronic stress, when our minds are in a constant state of worry, like in our examples at the beginning of the lesson. Your boss is no longer yelling at you, but the state of stress is lingering anyway. Your roommate hasn't started a fight yet, but you're already experiencing stress about it. The stress response remains even when the stressor is not present. This type of stress can undermine both our physical and mental health.

Your Immune System

Chronic stress harms us by working against our immune system. Your immune system helps protect your body by working to fight against infection and disease. When we experience stress, our brain causes a reaction that readies our body to fight or run from the source of stress, but these reactions also weaken our immune system response. One chemical that plays an important role in this is cortisol, which is released when we experience stress. This triggers a decrease in inflammation and white blood cells, both of which help us fight against germs and illnesses.

There are few side effects to a temporary increase in stress; however, anxiety, depression, or insomnia can occur when stress is experienced over a long period of time. Prolonged stress also puts a person at risk for high blood pressure, digestive problems, or heart disease. And remember, this is all in addition to the weakened immune system that is less able to fight off illnesses!

Have you ever heard someone say that they worried themselves into an ulcer? Have you ever caught a cold when you don't have time to deal with it because you have to meet a deadline at work? Maybe your uncle blames his nagging wife for his high blood pressure, or you know a soldier in a combat zone who suffers from insomnia. These could all be stress-induced illnesses.

Chronic stress hampers your bodies ability to fight off illness.

What You Can Do

Since chronic stress has the potential to hurt our immune system and harm us, it is important that we try to keep our stress levels low. We may not be able to control all of the things that cause us stress in our lives, but we can control how we react to the stress that we feel. A positive response to stress, one that helps us cope with all of the drama in our lives, will have a positive influence on our health as well.

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