Understanding Stress: Fight, Flight, or Freeze

The fight or flight response is the body’s natural response to stress.

It’s designed to give us an advantage or a boost when we’re faced with danger.

At least, that’s what it’s supposed to do.

Today, the fight or flight response becomes active from actions that aren’t immediately detrimental to our health — like getting stuck in traffic, impending deadlines at work, financial hardship, and breakups.

Over time, activating the fight or flight stress response too often or for too long can lead to illness.

In this article, we’ll discuss how the fight or flight (or freeze), response works, and how we can recognize it and protect ourselves from the negative impacts this system has on the body.

What Happens In The Body When We’re Stressed?

The human body is well adapted to manage stress. Our bodies are capable but fragile. We’re easily killed or maimed by injuries, lack of food, or attack from wild animals.

As humans evolved, we’ve developed a unique approach to increase our odds of survival when faced with a stressful situation. This system is referred to as the fight or flight system. The more accurate depiction for this system is “fight, flight, or freeze” — because it’s common for people to lock up, frozen in place when faced with a dangerous situation or stressor as well.

This system activates spontaneously, in the spur of the moment without conscious thought.

So what actually happens when we’re stressed? How does this system improve our odds of survival?

Stage 1: The Trigger

The first stage of the fight or flight response begins at the trigger itself.

This system is in place to help us avoid physical harm to the body (encountering a hungry animal or standing too close to a cliff face) or other stresses that would negatively affect our underlying instincts and drives (such as reproduction).

Let’s use an example for the sake of this article. A good example would be coming face to face with a sabre tooth tiger — an animal that would stand a high chance of killing a human.

Stage 2: The Amygdala Triggers the Fear Response

The amygdala is a special region of the brain responsible for detecting potential danger to the body. When it becomes active, it causes us to experience what we call fear.

The amygdala takes sensory information from the eyes and ears to recognize the tiger and immediately registers it as a threat. It then sends a signal to another region of the brain called the hypothalamus to carry out the response.

Stage 3: They Hypothalamus Orchestrates Physiological Changes in the Body

The hypothalamus is like the control centre for the body. Normally, it works to maintain equilibrium between the various organ systems of the body — a process called homeostasis.

However, once it receives signals of danger and fear from the amygdala, it shifts focus completely and forces the body out of balance. It changes the balance to optimize for survival by sending a cascade of chemical messages around the body.

Key Changes Involved With The Fight, Flight, or Freeze:

  • Heart rate increases — pushing blood and oxygen around the body faster to allow for a higher metabolic load
  • Airways to the lungs widen — allowing more oxygen to flow through with each breath
  • Blood pressure increases — forcing blood into the muscles faster to ensure maximum energy output as we use them to either fight or run away from danger
  • Pain tolerance increases — endorphins block pain signals from reaching the brain to allow us to fight or run despite serious injuries
  • Immune and digestive function shuts down — energy is preserved from functions that aren’t immediately essential to fighting or escaping
  • Blood sugar increases — the liver dumps extra sugar into the bloodstream to provide ample energy for the muscles to operate at a high energy output when we need them
  • The pupils dilate — allowing us to see more in our periphery and see more clearly in the dark
  • Blood clotting factors increase — preparing the body to form scabs and stop blood loss after an injury

This is just a few of the primary examples of what happens during the fight or flight response. There are hundreds of other, smaller tweaks the hypothalamus and other related endocrine organs make to optimize the body for a fight or to run away to safety.

Stage 4: Recovery

Let’s say we managed to survive the attack — we were somehow able to kill the tiger in a fight, or managed to outrun and outmanoeuvre the tiger to safety.

Now the body needs to reverse the changes made during the fight, flight, or freeze response. This system is only designed to operate for a short period of time — just long enough for us to get to safety.

If the fight or flight response is active for too long, it can lead to all kinds of problems — such as insomnia, anxiety, depression, lowered immunity, heart disease, and much more.

A key part of this system relies on our ability to turn it off when we no longer need it.

Heart rate and blood pressure revert back to resting levels, the immune and digestive systems kick back on, and blood sugar stabilizes, and the body starts to focus on repairing any damage that may have occurred during the incident.

The Problem With Fight, Flight, or Freeze In The Modern Human

Our ability to respond to stress is very useful as humans. It evolved during a time where we were integrated with our environment much more than we are today.

We still need the fight or flight response today. If someone robs or attacks us, if we get into a car accident, lost in the woods, or find ourselves in any dangerous situation — we rely on the fight or flight response to help us get out of harm’s way.

The problem is that this system wasn’t really intended to navigate the types of stress we experience today — such as deadlines, financial stress, constant upward comparison to social media influencers, or the frustration of being in traffic.

None of these forms of stress threatens our lives. And all of them tend to happen frequently or last for long periods of time.
It’s this constant activation of the fight or flight, without proper opportunity to relax and recover that makes us sick.

Over several days, weeks, months, or years — the accumulation of constant fight or flight stimulation can shift the balance from healthy to unhealthy. Stress is thought to be one of the leading causes of health conditions like anxiety, depression, autoimmune disease, and heart disease.

So, What Can We Do?

Now that we’ve covered what the fight, flight, or freeze response is, what can we do to prevent it from affecting our health?

Here are three simple steps to mitigate the damage this process can have while allowing it to serve us when we need it most.

1. Learn To Recognize When You’re Stressed

The first step to resisting the negative impact stress (and the fight, flight, or freeze) response has on the body, is to understand it — which is a step you’ve already taken by reading this article.

Learning how the fight or flight response works, and being able to recognize it when it happens to you is the first step.

Next, you should ask yourself whether feeling this way is appropriate to the situation.

Road rage is a great example of this. We have a strong tendency to become stressed and angry while driving. If someone cuts us off, is driving too slow, or didn’t turn their blinker on — it causes visceral stress in the body, which activates the fight or flight. This response is not only unhelpful for navigating through traffic safely; it can actually increase our chances of having an accident.

Once we learn to recognize when we’re feeling this way, it becomes easier to shut it off again.

2. Support the Recovery Process

The next step is to focus on activities that promote the recovery side of the process. While fight or flight is important, recovery is equally critical. We need to be able to effectively shut-off the stress response so our body can return to normal balance and begin the repair process.

You can achieve this by making an effort to do things that promote the recover part of the process.

A few examples of ways you can promote recovery:

  • Meditation or breathwork
  • Doing activities, you enjoy doing
  • Spending time with people you love
  • Prioritizing sleep
  • Taking sufficient time off work
  • Escaping on trips every once in a while

3. Increase the Threshold For Stress Triggers

It’s also important to take steps to increase the severity of stress needed to activate the stress response in the first place.

For example, someone with a low threshold may experience a full fight or flight reaction to something as nominal as the printer jamming at work. This is not life-threatening in any way and only offers a minor interruption in your daily workflow. However, for someone with a low threshold, this can register in the brain the same way a serious threat might.

If you can increase the threshold before your brain decides “this is a serious problem, we need to sound the alarms” — you’re going to experience this stress response much less frequently, and with much less severity each time.

It’s better to save this reaction for when it really counts — aka when we’re in real, legitimate danger.


There are a few ways to increase the threshold for stress, but the most reliable is through the use of adaptogens.

An adaptogen is a plant or animal extract that targets the hypothalamus or adrenal glands to reduce the stress response at its source. They’ve been used for centuries all over the world to promote general health and longevity. The reason they’re so useful for overall health is because of their effect on mitigating stress.

Here are some of the best herbal adaptogens to consider using yourself: