A big deadline at work. A life-changing event. A public speaking engagement. The thousand daily tasks that never seem to get finished. All of these things cause stress. But what is the purpose of stress in our lives, and is there anything positive that comes from feeling stress?

What is stress?

Stress. We hear the word nearly every day and probably say it just as often. Phrases such as, “I’m stressed” or “That was stressful,” fly off the tongue, but what do they really mean?

Stress, a physical reaction, results from stressors—changes in your environment or threats to your well-being. These demands can be short-term, often called acute stress, or long-term. They can result from outside influences, such as work or home life, or physical conditions, such as a chronic pain, an illness, or hunger. People often think of stress in terms of negative events, but happy times can also cause stress.

For example, did you know marriage ranks higher than losing a job or experiencing the death of a close friend on a widely used stress scale? The Holmes-Rahe Stress Inventory ranks common life events in terms of stress. The greater number of events on the list a person experiences in any given year, the greater that person’s risk of a stress-induced health breakdown. Significant life events require adaptability, resilience, and coping skills—even if they’re positive.

What is the purpose of stress? 

Stress is an evolutionary response. 

When the body senses an event that requires an additional burst of instinctive action, adrenaline and cortisone flood the body in vastly increased quantities. Neurotransmitters also signal the brain to feel emotions such as fear. This fight-or-flight response can be helpful in times of immediate physical danger. In those cases, the body’s functioning returns to normal after the threat passes.

Out on the plains of Africa, this helped our earliest ancestors to avoid getting devoured by lions. On today’s city streets, it helps us leap quickly out of the way when a car swerves towards the curb. It sets our heart racing when a clap of thunder or a bolt of lightning hits a little too close.

Adrenaline increases the heart rate and gets the blood pumping. This rush of blood also delivers more oxygen to our organs, including our brain and our muscles, enabling them to work more quickly and effectively, decreasing reaction time.  At the cellular level, the purpose of stress is a protective one, but it also helps us in other ways. When we are called to speak in public, adrenaline helps us think on our feet and come up with clever answers to unexpected questions.

Our bodies are designed to handle this sudden release of adrenaline and cortisone in response to emergency situations. However in the modern world, stress more frequently results from navigating office politics and family drama rather than confronting an angry black bear. These ongoing pressures result in a chronically stressed system on high alert for a black bear that never materializes.

Why is too much stress bad for our health? 

Whether the stress is good stress like the kind you feel on a roller coaster or on your wedding day, or bad stress like the death of a loved one or too many commitments and not enough time, we are able to use this response to our advantage.

The problem with stress becomes when we are unable to turn off the response by moving away from the stressful situation. A toast at a wedding is a brief, stressful event, but what if you had to be in the front of the room, speaking to a crowd for weeks at a time? What happens if, after you turn the big project into your boss, she turns around and hands you another, equally large and equally stressful one?

The point of a reaction to stress is a quick burst of responsive energy, followed by a restful period of recovery. If we are unable to have that restful period, then stress becomes a negative thing, and the results can be chronic.

Symptoms of chronic stres