Written by Artemis Stefani, PhD.

Read this blog on Substack.

You’re stuck in traffic.

photo: unsplash

You’re uncertain how late you’ll be for the only job interview you landed after months of job hunting.

Your heart’s racing. Your palms are sweating.

Your phone has no reception, and there is no way to notify anyone.

Each passing minute without getting any closer to your destination feels like a one-way route to Disaster City.

---

This seemingly annoying – yet mundane – moment is a classic example of daily stress. But have you ever paused to wonder what’s happening inside your body during such moments? Have you ever noticed your thoughts when stress hits or how long it takes you to feel ‘normal’ again?

Insights from science are helping us better understand how stress impacts our health in ways we might not even be aware of. If we understand the impact of stress on our health, we can prevent negative consequences by intervening early. In this post, we’ll delve into the basics of the science behind stress and why it matters.

---

Stress Science 101

Stress involves two key concepts: stressors and stress responses. Stressors are ‘threatening’ events that provoke a physical or psychological reaction in us. That reaction is what we call the stress response. It’s important to differentiate between the two, as, without them, the discussion around stress becomes awfully complicated.

Each time we face a stressful event, our body activates systems designed to help us cope. Information about a threat (i.e., a stressful event) gets passed on to our brains. The amygdala, an almond-shaped brain structure that detects threats, signals the hypothalamus. The hypothalamus then activates two main systems: the sympathetic-adreno-medullar axis (SAM; a rapid response) and the hypothalamic-pituitary-adrenal axis (HPA; a slower and longer lasting response). The SAM axis triggers the release of adrenaline and noradrenaline, causing our heart to race and our breathing to quicken – preparing us for action. In turn, the HPA axis activates a series of processes that lead to the release of cortisol, a stress hormone associated with energy, immune response modulation, and cognitive function.

Once the stressful situation is over, the parasympathetic system’s activity increases to counterbalance the previous stress response by slowing our heart rate and relaxing our muscles, restoring the body to a balanced state.

---

From traffic jams to allostatic loads: How stress drives us (until it doesn’t)

Stressors lurk in traffic jams, tight deadlines, and minor disagreements. These daily hassles are part of life. Some stressors stem from big life events, like losing your job or going through a breakup. Even seemingly positive life events can be stressful, like getting married, buying a home, or moving to a new country.

When stressors linger on, such as having long-term financial worries or living in an unsafe neighbourhood, they can turn into chronic stressors, weighing us down over time.

To understand how the stress response works, picture your body as an engine: while a little heat (stress) is normal and keeps things running smoothly, too much for too long can cause damage. If the engine is not allowed to cool down (through relaxation) or if it is not maintained, it risks severe malfunctioning.

This cumulative toll is known as allostatic load – the hidden cost that chronic stress has on our bodies. Over time, this constant activation can contribute to health issues including disrupted immune function, mental health disorders and cardiovascular disease. This is why it’s important to find time to de-stress and allow our body to recover through exercising, setting boundaries, taking breaks, or spending time in nature.

photo: unsplash

But, don’t think of stress as the enemy. At optimal levels, our stress response gets us out of bed, keeps us motivated, and helps us stay alert and focused in situations of high stakes.

Whether that’s surviving a tight deadline or a grizzly bear, your stress response comes to the rescue.

---

Stress: a key part of the human experience

How does your body feel when you’re stressed? Is it a knot in your stomach? Is it trouble breathing normally? And how does your behaviour reflect that?

If you ask a loved one the same questions, you’ll likely get different answers.

Let’s revisit the earlier scenario of being stuck in traffic on the way to a job interview. For some, this event might trigger panic and a cascade of negative thoughts. Others might feel frustrated but stay composed, accepting the situation or distracting themselves with something else. These differences highlight that the experience of stress is deeply personal and can vary from person to person.

Each person has a different definition of what stresses them out and how they respond to it. You can also see that some answers may be more popular than others. Note that the offered choices may not necessarily capture the extent of your stress experience. To make things slightly more complicated, if I were to ask the same questions two weeks or two months ago, your answers might have been different.

figure created in Biorender

---

Decoding stress: Why it matters

Feeling stressed goes beyond simply identifying moments or feelings of discomfort: it’s a multilayered process involving both our body and mind, affecting our mood, physical health, and overall well-being.

Stress research allows us to distinguish between when stress is helpful, motivating us to meet deadlines or tackle life’s challenges, and when it becomes harmful, leading to a downstream spiral of issues such as mental exhaustion, obesity, depression, and heart disease.

Stress research allows us to predict when people might become ill before they do. By identifying who is more likely to get ill and when, we can design personalised solutions at the right time. Studying stress also helps us understand more about resilience: why do some people adapt successfully and thrive despite several adversities whereas others struggle?

photo: substack

So, next time you’re stressed – whether stuck in traffic or overwhelmed at work – remember, there’s more happening beneath the surface than just a feeling(1). And, thanks to ongoing research, we’re getting closer to decoding the unseen.

---

Interested in more? Listen to our Podcast here: Stress Navigation Podcast

---

---