Stress: The slow burn on your health

You can’t see it. You can’t hold it. But every day, it’s breaking you down from the inside out. Stress doesn’t need a weapon, it uses your own body against you, quietly rewiring your brain, disrupting your hormones , and weakening your defences (Mariotti, 2015).

You tell yourself it’s just part of life. Everyone’s tired. Everyone’s busy. But this constant strain isn’t normal, it’s chronic stress. And it works like the “boiling frog”. If you drop a frog into boiling water, it jumps out immediately. But if you heat the water slowly, it doesn’t notice the danger until it’s too late. Chronic stress is that slow heat. It builds gradually, keeping your body’s alarm systems stuck on high alert, burning through your health cell by cell until one day, the damage is done (Roberts & Karatsoreos, 2021).

Not all stress is bad. In fact, your body is built to handle and even benefit from short bursts of it (Roberts & Karatsoreos, 2021).

• Good stress (eustress) is like a shot of adrenaline before a big presentation or during a workout. It sharpens focus, boosts performance, and then fades away once the challenge passes.
  
  

• Bad stress (distress) is the kind that lingers. It’s the unpaid bill you worry about for months, the relentless workload, the constant “what ifs” playing in your mind. Instead of switching off, your stress response stays stuck in the “on” position.

Here’s where the problem begins. When your brain senses a threat, whether it’s a car swerving in front of you or an email from your boss at 10 p.m, it triggers the fight-or-flight response.

• Your hypothalamic–pituitary–adrenal (HPA) axis fires up.

• Your adrenal glands release cortisol and adrenaline.

• Your heart rate climbs, your breathing quickens, and your blood sugar rises to fuel your muscles (Knezevic et al., 2023; Noushad et al., 2021).
  
  

In the short term, this is lifesaving. But when the stress signal never shuts off, these changes stop being helpful and start becoming harmful. High cortisol over weeks, months, or years begins to:

• Disrupt blood sugar control

• Weaken your immune system

• Fuel chronic inflammation

• Change the structure and function of your brain (Mariotti, 2015; Roberts & Karatsoreos, 2021).
  
  

This is how stress slowly shifts from being your body’s emergency helper to its most destructive long-term threat. And it doesn’t just affect one part of you, it works its way through nearly every system in your body.

One of the first places chronic stress leaves its fingerprints is in your brain. Studies show it can literally change its shape and chemistry over time (Roberts & Karatsoreos, 2021).

• Hippocampus (memory & learning) – Research has found that chronic stress can shrink this region, making it harder to store new memories or recall old ones (Roberts & Karatsoreos, 2021).
  
  

• Amygdala (fear & threat detection) – Stress makes this area more reactive, which means you may feel anxious or “on edge” even in safe situations.
  
  

• Prefrontal cortex (decision-making & emotional control) – This vital area can weaken, making it harder to stay calm, focus, and think clearly under pressure.
  
  

Why it matters: These changes can affect how you think, learn, and manage emotions , setting the stage for anxiety, depression, and memory problems later in life.

Your heart is built to handle short bursts of activity, like running to catch a bus. It’s not designed to live in “go mode” 24/7.

• Blood pressure & heart rate – Prolonged stress keeps both elevated, straining the heart muscle.
  
  

• Inflammation in blood vessels – Chronic stress can inflame vessel linings, making them more vulnerable to damage (Mariotti, 2015).
  
  

• Plaque build-up – Research links chronic stress to faster build-up of fatty plaques in arteries, raising the risk of heart attack and stroke (Mariotti, 2015).
  
  

Why it matters: Heart disease is still a leading cause of death worldwide. Stress quietly increases your risk without you feeling it.

Stress hormones like cortisol are meant to fuel quick action, not stay high all the time. When they do, your metabolism takes a hit.

• Belly fat & blood sugar – Cortisol encourages fat storage around your middle and raises blood sugar.
  
  

• Insulin resistance – Over time, this can make your body less responsive to insulin, a major step toward type 2 diabetes (Stefanaki et al., 2023).
  
  

• Hunger hormone disruption – Stress can skew leptin and ghrelin levels, leading to intense cravings for sugary, high-calorie foods.
  
  

Why it matters: These changes make it easier to gain weight and harder to lose it, while increasing your risk for diabetes and metabolic syndrome.

Your gut, often called your “second brain” is highly sensitive to stress.

• Microbiome changes – Chronic stress can disrupt your gut’s bacterial balance, which influences digestion, immunity, and even mood (Westfall et al., 2021).
  
  

• Weakened gut barrier – Stress can make the intestinal wall more “leaky,” letting harmful substances enter your bloodstream.
  
  

• Digestive discomfort – This imbalance can cause bloating, cramping, and make you more sensitive to certain foods.
  
  

Why it matters: A healthy gut supports not only digestion but also your immune system and mental health. Stress can undermine all three.

When stress sticks around, it changes how your body uses and stores energy, often at the expense of your strength.

• Muscle breakdown – High cortisol can cause your body to break down muscle for fuel (Stefanaki et al., 2023).
  
  

• Fat in muscle & bone marrow – Stress can lead to fat deposits in muscle and bone marrow, making them weaker.
  
  

• Lower bone density – Chronic stress is linked to reduced  bone strength,  increasing osteoporosis risk.
  
  

Why it matters: Losing muscle and bone strength doesn’t just affect athletes, it impacts your daily mobility, recovery time, and risk of fractures as you age.

Your immune system also pays the price for long-term stress.

• Initial boost, then burnout – Short-term stress can activate immune defences, but over time, they weaken.
  
  

• Chronic inflammation – Prolonged stress fuels low-grade inflammation, which is linked to autoimmune diseases and other chronic illnesses (Noushad et al., 2021).
  
  

• Slower healing – Cuts, infections, and even workouts take longer to recover from.
  
  

Why it matters: A weakened immune system means you’re more likely to get sick and take longer to bounce back all while fuelling conditions linked to inflammation.

It’s not just the stress itself that matters, it’s what you believe about it.
A large U.S. study found that people who reported high stress and believed it was harming their health had a 43% higher risk of dying early (Keller et al., 2012).

Why?

• Negative beliefs can intensify your body’s stress response. If you expect stress to harm you, your heart rate, blood pressure, and stress hormones may spike even higher in challenging situations.
  
  

• It can affect your behaviour. Believing stress is damaging can make you less likely to exercise, eat well, or sleep enough — which in turn worsens its impact.
  
  

The good news? Reframing stress can make a difference. If you start to see stress as your body’s way of preparing you for a challenge, rather than a threat, you can change both your mindset and your physiological response.

Stress is sneaky. It builds slowly, and often you don’t realise you’re in overload until it starts showing up in your body and behaviour. 

Watch for:

• Constant fatigue, even after rest

• Frequent headaches or tense muscles

• Poor sleep or vivid, stressful dreams

• More digestive problems than usual

• Catching colds more often

• Feeling irritable, anxious, or “on edge”
  
  

If these feel familiar, your body may be telling you it’s time to step in and reset.

You can’t eliminate stress completely but you can strengthen your resilience and protect your health (Mariotti, 2015; Knezevic et al., 2023).

Research supports these simple, effective strategies:

• Move your body – Regular exercise lowers stress hormones and boosts mood. Even a brisk walk can help.
  
  

• Eat for your gut – A diet rich in fibre, fermented foods, and diverse plants supports healthy gut bacteria, which play a role in regulating stress responses (Westfall et al., 2021).
  
  

• Prioritise sleep – Aim for 7–9 hours of quality sleep. Poor sleep keeps cortisol levels high and makes you less able to cope with challenges (Morrison et al., 2022).
  
  

• Breathe with intention – Practices like mindfulness, meditation, or slow, deep breathing help shift your body out of “fight-or-flight” mode.
  
  

• Stay connected – Supportive relationships act as a buffer against the negative effects of stress.
  
  

• Challenge your thoughts – Swap “This is too much for me” for “I can work through this.” That mindset shift matters.

Stress will always be part of life. But how you respond and how you think about it, determines whether it carves away at your health or helps you grow stronger. Stress will always knock at the door, it’s how you answer that makes the difference.

If you’re ready to take the next step toward a calmer, more resilient you, we’d love to help. You can visit us in-store for tailored advice from our friendly team, or take advantage of our Click & Collect service for fast, convenient pickup of your essentials. For more science-backed tips on managing stress and supporting your wellbeing, explore our Education Hub online. And if you’re looking for extra support, you can browse our stress supplement collection to find the right fit for your needs.

Your health story is yours to shape and we’re here to help you write the strongest chapter yet.

Keller, A., Litzelman, K., Wisk, L. E., Maddox, T., Cheng, E. R., Creswell, P. D., & Witt, W. P. (2012). Does the perception that stress affects health matter? The association with health and mortality. Health Psychology, 31(5), 677–684.  https://doi.org/10.1037/a0026743

Knezevic, E., Nenic, K., Milanovic, V., & Knezevic, N. N. (2023). The role of cortisol in chronic stress, neurodegenerative diseases, and psychological disorders. Cells, 12(23), 2726.  https://doi.org/10.3390/cells12232726

Mariotti, A. (2015). The effects of chronic stress on health: New insights into the molecular mechanisms of brain–body communication. Future Science OA, 1(3), FSO23.  https://doi.org/10.4155/fso.15.21

Morrison, M., Halson, S. L., Weakley, J., & Hawley, J. A. (2022). Sleep, circadian biology and skeletal muscle interactions: Implications for metabolic health. Sleep Medicine Reviews, 66, 101700.  https://doi.org/10.1016/j.smrv.2022.101700

Noushad, S., Ahmed, S., Ansari, B., Mustafa, U.-H., Saleem, Y., & Hazrat, H. (2021). Physiological biomarkers of chronic stress: A systematic review. International Journal of Health Sciences, 15(5), 46–94.

Roberts, B. L., & Karatsoreos, I. N. (2021). Brain–body responses to chronic stress: A brief review. Faculty Reviews, 10(83).  https://doi.org/10.12703/r/10-83

Stefanaki, C., Paltoglou, G., Mastorakos, G., & Chrousos, G. P. (2023). Chronic stress and steatosis of muscles, bones, liver, and pancreas: A review. Hormone Research in Paediatrics, 96(1), 66–73.  https://doi.org/10.1159/000522540

Westfall, S., Caracci, F., Estill, M., Frolinger, T., Shen, L., & Pasinetti, G. M. (2021). Chronic stress-induced depression and anxiety priming modulated by gut–brain-axis immunity. Frontiers in Immunology, 12, 670500.  https://doi.org/10.3389/fimmu.2021.670500