“The greatest weapon against stress is our ability to choose one thought over another.” – William James

Stress can cause a plethora of health problems (and can even kill you) if you don’t learn how to manage it. With so many stressors in our world today, many of us live in a constant alarmed state. We have to deal with countless stimuli and inputs from the outside world, and filtering through all of it can leave us feeling exhausted and overwhelmed.

To give you an idea on just how widespread the stress epidemic has become, here are some startling statistics about stress according to The American Institute of Stress:

U.S. Stress Statistics


Percent of people who regularly experience physical symptoms caused by stress. 77%
Regularly experience psychological symptoms caused by stress. 73%
Feel they are living with extreme stress. 33%
Feel their stress has increased over the past five years. 48%
Cited money and work as the leading cause of their stress. 76%
Reported lying awake at night due to stress. 48%


As you can see, many people deal with extreme stress that can affect every aspect of their life. When stress becomes debilitating, it can cause physical as well as mental health problems. In this article, we’ll go over how exactly stress can impact the brain and body, and how you can learn to manage it.

Here’s how stress can make you sick and tired:

Stress drains the body of its energy stores since stress is meant to warn us of an impending threat. Our fight-or-flight response exists to give us adrenaline to decide how to respond to that threat: either run or fight back. In the modern world, we have near-constant stressors which keep our bodies in a persistent state of alert. As a result, our bodies begin to wear down since we have a harder time transitioning to a relaxed state of mind.

Most people don’t realize how interconnected our minds and bodies are, and that an imbalance in one can cause issues in both. Dr. Esther Sternberg, Professor of Medicine and Founding Research Director for the Arizona Center for Integrative Medicine at the University of Arizona at Tucson, has done extensive research on the links between the mind and body. Her research has included understanding the connection between the central nervous system and the immune system and studying how immune molecules made in the blood can affect brain functions that impact our emotions. In one of her best-selling books called The Balance Within: The Science Connecting Health and Emotions, Sternberg examines how our emotions, particularly stress, can impact our physical health.

An excerpt from her book explains how the parts of our brain that control stress may also play a role in our likelihood of developing certain diseases:

By parsing these chemical intermediaries, we can begin to understand the biological underpinnings of how emotions affect diseases…

The same parts of the brain that control the stress response … play an important role in susceptibility and resistance to inflammatory diseases such as arthritis. And since it is these parts of the brain that also play a role in depression, we can begin to understand why it is that many patients with inflammatory diseases may also experience depression at different times in their lives… Rather than seeing the psyche as the source of such illnesses, we are discovering that while feelings don’t directly cause or cure disease, the biological mechanisms underlying them may cause or contribute to disease. Thus, many of the nerve pathways and molecules underlying both psychological responses and inflammatory disease are the same, making predisposition to one set of illnesses likely to go along with predisposition to the other.


We are even beginning to sort out how emotional memories reach the parts of the brain that control the hormonal stress response, and how such emotions can ultimately affect the workings of the immune system and thus affect illnesses as disparate as arthritis and cancer. We are also beginning to piece together how signals from the immune system can affect the brain and the emotional and physical responses it controls: the molecular basis of feeling sick. In all this, the boundaries between mind and body are beginning to blur.

She goes on to explain how the constant stimuli we come in contact with can affect our stress response:

Every minute of the day and night we feel thousands of sensations that might trigger a positive emotion such as happiness, or a negative emotion such as sadness, or no emotion at all: a trace of perfume, a light touch, a fleeting shadow, a strain of music. And there are thousands of physiological responses, such as palpitations or sweating, that can equally accompany positive emotions such as love, or negative emotions such as fear, or can happen without any emotional tinge at all. What makes these sensory inputs and physiological outputs emotions is the charge that gets added to them somehow, somewhere in our brains.

Memory plays a powerful role in mediating our stress response, because a negative memory triggered by present events can change our mood in an instant.

Sternberg writes:

Mood is not homogeneous like cream soup. It is more like Swiss cheese, filled with holes. The triggers are highly specific, tripped by sudden trails of memory: a faint fragrance, a few bars of a tune, a vague silhouette that tapped into a sad memory buried deep, but not completely erased. These sensory inputs from the moment float through layers of time in the parts of the brain that control memory, and they pull out with them not only reminders of sense but also trails of the emotions that were first connected to the memory. These memories become connected to emotions, which are processed in other parts of the brain: the amygdala for fear, the nucleus accumbens for pleasure — those same parts that the anatomists had named for their shapes. And these emotional brain centers are linked by nerve pathways to the sensory parts of the brain and to the frontal lobe and hippocampus — the coordinating centers of thought and memory.

The same sensory input can trigger a negative emotion or a positive one, depending on the memories associated with it.

Our memories of certain experiences can affect how we respond to stress. Good stress motivates us to take action, while bad stress can immobilize us with fear and uncertainty.

Sternberg explains what happens in the brain when you become stressed:

As soon as the stressful event occurs, it triggers the release of the cascade of hypothalamic, pituitary, and adrenal hormones — the brain’s stress response. It also triggers the adrenal glands to release epinephrine, or adrenaline, and the sympathetic nerves to squirt out the adrenaline-like chemical norepinephrine all over the body: nerves that wire the heart, and gut, and skin. So, the heart is driven to beat faster, the fine hairs of your skin stand up, you sweat, you may feel nausea or the urge to defecate. But your attention is focused, your vision becomes crystal clear, a surge of power helps you run — these same chemicals released from nerves make blood flow to your muscles, preparing you to sprint.


…if you prolong the stress, by being unable to control it or by making it too potent or long-lived, and these hormones and chemicals still continue to pump out from nerves and glands, then the same molecules that mobilized you for the short haul now debilitate you.


She explains how chronic stress can harm your immune system:

The nervous system and the hormonal stress response react to a stimulus in milliseconds, seconds, or minutes. The immune system takes parts of hours or days. It takes much longer than two minutes for immune cells to mobilize and respond to an invader, so it is unlikely that a single, even powerful, short-lived stress on the order of moments could have much of an effect on immune responses. However, when the stress turns chronic, immune defenses begin to be impaired. As the stressful stimulus hammers on, stress hormones and chemicals continue to pump out. Immune cells floating in this milieu in blood, or passing through the spleen, or growing up in thymic nurseries never have a chance to recover from the unabated rush of cortisol. Since cortisol shuts down immune cells’ responses, shifting them to a muted form, less able to react to foreign triggers, in the context of continued stress we are less able to defend and fight when faced with new invaders. And so, if you are exposed to, say, a flu or common cold virus when you are chronically stressed out, your immune system is less able to react and you become more susceptible to that infection.

Managing Stress

Now that you know how stress can impact your physical and mental health, let’s talk about ways you can keep it under control.

  • Lifestyle changes: make sure you exercise at least 30 minutes per day, avoid smoking or drinking, eat a balanced diet, and take frequent breaks from work.
  • Relaxation techniques: meditation, yoga, and deep breathing exercises can help you learn to manage stress more effectively.
  • Herbal remedies: some herbal supplements such as valerian root, chamomile, and 5-HTP have been shown to help manage stress.