Stress, Cortisol, and the Adrenals: When ‘Fight or Flight’ Meets the Modern World

By - Mark Sisson

Understanding Stress

Most folks are aware that “fight or flight” is the body’s natural response to stress. When faced with a stressful situation, we either get aggressive or, in the words of a local surf instructor, we bail. This choice depends upon our perception of the circumstances and our corresponding judgment of the odds of success. The “fight or flight” response is, in terms of energy preservation, tremendously efficient. And it is very effective at ensuring greater odds of survival. This makes sense to everyone on a visceral level, but do you know the physiological mechanisms involved?

The fight or flight response begins in the brain. Various regions operate in concert to detect, sense, decode, and respond to a stimulus. Though there are a few different pathways for a given feeling (like fear) to travel, it is ultimately the hypothalamus that is responsible for triggering the fight or flight response. Once the hypothalamus goes to work, what I call your survival systems, i.e. the “gut”, kick into gear. They are the nervous system and the adrenal-cortical system.

Enter physical symptoms: sweating, heart palpitations, muscles tensing, hearing sharpening. You are now extraordinarily alert, but only on the issue at hand: concentration and awareness of anything else fly out the window. The nervous system has flooded your body with adrenaline (scientists often refer to this as epinephrine) and noradrenaline (norepinephrine). Meanwhile, the adrenal-cortical system (which produces these hormones) becomes activated by way of the pituitary gland. The pituitary gland secretes a hormone known as ACTH (adrenocorticotropic hormone…say that three times fast). ACTH journeys - via the bloodstream - to your adrenal cortex, where these small organs will pump out as many as 30 different hormones to address the stressful situation at hand (the adrenals are “fed” by cholesterol). And your immune system temporarily shuts down so your body can utilize all its resources to deal with the perceived threat.

The adrenal cortex produces cortisol, DHEA, estrogen and testosterone, among many other hormones. It’s a beautiful system. Unfortunately, what worked for our old friend Grok does not, I believe, work so well for us. Simply put, our modern lifestyle subjects us to a potentially enormous amount of stress on a daily basis that the body has simply not evolved to handle. To my mind it’s a bit like “deer in the headlights”. We have a big deer overpopulation problem in my area, and you always hear comments along the lines of how dumb the deer are around automobiles. Well, in my opinion they’re not so dumb - in evolutionary terms, after all, cars are very new on the scene. The deer simply haven’t adapted the appropriate stress response. Is it so different for humans?

Theoretically then, persistent, low-level stress - which the body unfortunately interprets as warranting a “fight or flight” response - is destructive to health. In other words, being stuck in traffic for two hours a day, every day, is the equivalent of a serious survival threat to your as-yet “primal” brain, and the adrenals pump accordingly. Cortisol serves many important functions, including the rapid release of glycogen stores for immediate energy. But persistent cortisol release requires that other vital mechanisms effectively shut down - immunity, digestion, healthy endocrine function, and so on. Among other stress-health associations, the link between elevated cortisol and weight gain has already been established.

At this point I hope you can begin to imagine the potential health ramifications of what is often called “adrenal fatigue”: daily compromised immunity, continuous stress hormone release, being “on edge” generally, exhausted sex hormones (remembering my admittedly pet theory of why male endurance athletes often suffer from diminishing testosterone production and consequent receding hair). Your body thinks it must survive at all costs - and is there ever a cost.

Though I’m no Green, nor do I think moving to the woods to commune with the grubs is a viable (or desirable) solution to mitigating stress, the tremendous volume and scope of stressful stimuli present in the modern, fast-paced lifestyle may play a very critical role in the high rates of diabetes, metabolic syndrome, obesity, depression and anxiety we’re seeing (among many health problems). At any rate, I firmly believe this to be so. (Humorous note: apparently shopping is physically stressful for men. But then, planning holiday events and managing social obligations is stressful to women. At the risk of announcing my bah-humbugness to the world, the holidays are inordinately stressful to everyone.)

Managing Stress

Managing stress, then, is paramount to maximizing optimal health. To the extent that you can, reduce the “noise” in your life - from entertainment, from frivolous or excess obligations, from fractious relationships, from debt, and so on. Managing stress is a very big topic indeed, and we’ll be addressing it more in future posts. For now, here are the key factors I believe are necessary to reducing stress:

- Consume antioxidant-rich foods such as fruits and vegetables. I also recommend a multivitamin that contains a comprehensive and potent antioxidant profile. Completely avoid processed, empty calories found in snacks, junk food and fast food.

- Consume adequate beneficial fats to utilize antioxidants, vitamins, enzymes and co-factors. Wild Alaskan salmon, pure fish oil pills, olive oil, nuts and avocados are good places to start. I don’t go in for the Omega-enhanced Tropicana or miracle mayonnaise, personally.

- Manage expectations: your own and others’. Ambition and motivation and generous support are all great traits to possess. But don’t over-promise to others or yourself. None of us knows the future.

- Exercise daily. I cannot stress this enough. Exercise releases endorphins and helps to regulate the production of critical brain hormones.

- Unhook daily. Most of us spend so much time on the input-output cycle, we don’t give adequate time to simply absorbing it all. Reflect, relax, restore. I personally like to spend a little time each day reflecting on what I am grateful for (I call this doing my “appreciations”.) Prayer, meditation, singing, cooking and other activities that get you out of your head and into the moment are vital to helping you manage the stress of constant stimuli and energy demands. “Think positive” is nice advice, but it’s tough to do if you are at your limit. It’s easier to find an action that naturally lends itself to positive thinking and feeling, rather than trying to control your thoughts. That in and of itself can become stressful. Find an immersing action that works for you and do it religiously.