The Harm of Constant Stress Hormones

It's the night before a big exam and you can’t sleep. It's 2am, and you begin to worry about your inability to sleep which in fact keeps you more awake. Ever notice that? The night before an exam or the first few hours prior, your body feels like it's going to sink below the ground. Sweaty palms, elevated heart beat, or the need to use the bathroom more frequently are all signs of this. These are not classified as “just nerves” but they are legitimate stress responses. Your body essentially thinks the exam is dangerous and wants you to run away. But why? 

What are hormones? 

Hormones are chemical messengers which travel all over the body to regulate metabolism. Metabolism is a complex set of interacting and interdependent chemical reactions which every living organism needs to survive. Once hormones are produced, they bind to specific molecules triggering changes in cell behavior and function. As they travel through blood streams, they essentially tell our bodies when to do what and to what extent. 

Hormones are secreted by a system called the endocrine system. This encompasses a network of organs and glands which secrete such chemical messengers. The thyroid, for instance, in the neck is part of this system. However, the lack of secretion of specific hormones can lead to development of autoimmune diseases, like hypothyroidism. 

Hence, clearly, hormones are hugely responsible for controlling multiple aspects of how our bodily functions, but how do they relate to stress?

The stress hormones

When a stressful moment hits, your body shifts into a biologically different mode. This shift is driven by a group called stress hormones. These stress hormones are prepping your body for action.

There are 2 main types of stress hormones:

1. Adrenaline 

2. Cortisol 

Adrenaline acts as a short term stress-response messenger, with a half life of 2-5 minutes. It is integral to remember that adrenaline activates the body's fight or flight response. During peaks of fear, excitement, or anxiety (common with stress) glands near the kidney are prompted to release the hormone. Upon this release, you are likely to experience heightened senses, a rise in blood sugar levels (hence more energy), a rise in heart rate and even sweat. Adrenaline acts as an immediate responder and has positive effects in the short run. It can enhance focus, reaction rate and make you feel more capable and accomplished. It is essentially a boost button in short time frames. 

On the other hand, cortisol is a longer-term stress hormone. In the sense, it has a greater half-life (up to 90 minutes) and is much more controlled in release. It follows the body's sleep clock, or scientifically referred to as circadian rhythm. As a result, it is sustained throughout the day but its concentration varies. During periods of prolonged stress, like a mid-life crisis, cortisol outcompetes adrenaline and sustains energy, thus it is referred to as the primary stress hormone (it is produced more frequently). However, sustained high levels of cortisol have detrimental effects on the body.

Adrenaline structure (left) and cortisol structure (right)

The downside

When adrenaline, and cortisol are elevated for extended periods of time, the body pays a price. Over time, their sustained presence keeps the nervous system constantly alert. This can overstimulate the nervous system which can worsen sleep quality by interrupting sleep cycles. 

Cortisol also breaks down high levels of glucose to provide the body with energy during times of stress. If your stress response is stretched out, you risk the possibility of depleting long term reserves and can't fully recover which traps you in a state of constant fatigue. 

Furthermore, cortisol suppresses immune system activity. In the short run, this can reduce inflammation, but in the long run it suppresses the ability of your white blood cells which weakens your immune system. This also explains why you get sick more easily when stressed. 

How to manage stress?

As stress is caused by fundamental body systems, namely endocrine and nervous system, managing stress is integral to maintain homeostasis, or internal balance.

Stress management varies person to person but establishing regular habits and techniques such as yoga, mindful breathing or anything that distracts your mind from your daily tasks has shown to be really beneficial. Physical movement can also “burn off” stress hormones by the activation of other chemical messengers. 

Allowing your stress response to switch off is essential for preserving long term physiological health. 

References

Cortisol Matters (2025). What Is Cortisol - Cortisol Matters. [online] Cortisol Matters. Available at: https://www.cortisolmatters.com/patient/what-is-cortisol [Accessed 8 Feb. 2026].

Health Direct (2025). Hormonal System. [online] Healthdirect.gov.au. Available at: https://www.healthdirect.gov.au/hormonal-system-endocrine [Accessed 8 Feb. 2026].

Lillis, C. (2024). What to know about stress hormones. [online] Medicalnewstoday.com. Available at: https://www.medicalnewstoday.com/articles/stress-hormones [Accessed 8 Feb. 2026].

Mayo Clinic (2023). Chronic Stress Puts Your Health at Risk. [online] Mayo Clinic. Available at: https://www.mayoclinic.org/healthy-lifestyle/stress-management/in-depth/stress/art-20046037 [Accessed 8 Feb. 2026].

Mental Health America (2025). What Is Adrenaline? | Mental Health America. [online] Mental Health America. Available at: https://mhanational.org/resources/what-is-adrenaline/ [Accessed 8 Feb. 2026].

Selleckchem (2024). L-Adrenaline. [online] selleckchem.com. Available at: https://www.selleckchem.com/products/L-Adrenaline-Epinephrine.html [Accessed 8 Feb. 2026].