Lions, Zebras and Michael Jordan

Dean Smith was Michael Jordan’s basketball coach at the University of North Carolina.  Not only was he was a legendary coach…he was also very quotable. One of my favorites is, “If you treat every situation as a life and death matter, you’ll die a lot of times.” Coach Smith was probably referring to the stress of important basketball games, but it’s a quote that illustrates just how dangerous constant emotional strain can be… both psychologically and physically. In fact, scientific studies confirm that chronic stress contributes significantly to chronic disease and can most definitely take years off your life. With that in mind, I’d like to discuss why mental tension can be so insidious.

The Origins of Stress in a Psychological Sense

The term stress, as it applies to the human condition, is a relatively recent invention. Previously, the concept was used almost exclusively in the field of physics to describe the strain that occurs in material objects when an outside force is applied. For example, metal beams are stressed by weight bearing down upon them.

It was an endocrinologist by the name of Hans Selye who first used the term “stress” to describe the phenomenon that we all know so well today. His first published work on “the stress syndrome” (also known as the General Adaptation Syndrome) was published in 1936 and the word “stress” was not used widely to refer to humans until at least 20-25 years later. In the last 50-60 years…stress has certainly become part of the human language and the human experience.  

Selye worked with sick patients in a hospital setting and he noticed that shared one trait in common–they all looked as if they were under great physical distress. He believed there was some non-specific strain (emotional stress) that was interfering with normal biological processes.

Selye’s revelation ushered in a whole new field of research, which investigates the impact of emotional stress on physical health. Today, we understand the evolutionary wisdom of stress, but also why it can be so maladaptive (particularly for us modern humans). Understanding the biological underpinning of stress can help us mitigate some of its risks.

The Fight or Flight Response in Action

Imagine a herd of zebras on the Serengeti. These graceful animals must be swift and highly alert to avoid hungry predators like lions. At a moment’s notice, a zebra must be ready to devote all its attention and energy to making a quick escape.

Thankfully, Nature has equipped the zebra with a biological mechanism that allows it respond rapidly to a sudden threat. It’s called the “fight or flight” response…you’ve undoubtedly heard the term before. Essentially, when the lion starts chasing, the zebra is flooded with hormones that enable it to respond to the threat with a quick burst of energy.

Hormones such as adrenaline and cortisol–the so-called stress hormones–provide the zebra with instant strength and energy. The pupils dilate, blood pressure and heart rate increase, blood glucose levels rise, and muscles are flooded with blood for the great escape….or the fight, if it comes to that. Essentially, the zebra’s energy and resources are diverted where they are needed the most–towards the heart, lungs, and muscles–so that the zebra stands the best chance of getting out alive. We use the term “upregulation” to describe what happens to all of the body systems that are kicked into high gear by a stress response.   

At the same time as all of those body systems are upregulated, there are a whole set of other body systems that are simultaneously “downregulated.” These are the systems and bodily functions that are not required for immediate or short term survival…so it’s ok for a zebra to turn them down until the threat passes. During a stress response, downregulated systems include: gastrointestinal function, immunity, reproduction/fertility, wound healing and repair etc.  Of course, a zebra does not need to be worried about digesting a meal, fighting an infection, or getting romantic when a lion is in pursuit.  

The Perils of Chronic Upregulation and Downregulation

The good news for a zebra is that the lion ordeal usually ends fairly quickly. In the short term, upregulation and downregulation are perfectly fine…in fact, they are a necessary part of getting out of a dangerous situation alive. But when the lion is nipping at your heels for weeks, months, or years…you’re going to have trouble.

Evolution has provided human beings with the same stress response mechanisms as zebras. If you are in a life-threatening predicament it’s a great repertoire to have. Of course, most people today are not in acute threat-to-life situations on a daily basis. But our stress response system still responds to normal hassles and minor threats–workplace grievances, traffic snarls, and domestic disputes–with the full-blown fight or flight response.

That kind of chronic overreaction takes its toll on the body in ways that include damage to the the systems/organs that upregulated and those that are downregulated as well. Chronic stress can lead to higher blood pressure, higher blood sugar, muscle tension, and insomnia as well as impaired immune system function, poor digestion, and slowed wound healing and repair. Studies show that stress which causes elevated cortisol levels for prolonged periods can undermine cardiovascular health, fertility, the endocrine system, and much more.

It’s perfectly normal for the “fight or flight” system to be activated on occasion. Chronic stress, however, can wreck havoc on your health over time. Thankfully, there are things you can do to tame the fight or flight response and counteract the effects of stress hormones. Follow a whole food, plant-based diet, walk for at least 30 minutes per day, add a daily mindfulness practice to your life, keep a gratitude journal, and remember the words of the great Dean Smith… If it’s not life and death, there’s no good reason to act like it is.

Take good care,

Dr. Joshua Levitt