Diving into Cortisol: Understanding Stress Hormone Impact on Health


Stress is a huge topic – I’ve written a book about it! Everybody experiences it and yet very few people address the problem head on. For a problem to be solved, we need to understand the root cause. I explore that in my book, blog, and upcoming podcasts. When exploring stress you will continue to hear of certain hormones and physiological processes that occur. Cortisol, the chronic stress hormone, is one of those and something I want to explore in more detail. Historically when we experienced long-term stress it would be due to life threatening concerns. Things like food shortages or natural disasters. Cortisol would switch on and it would support our battle for survival – activating the sympathetic nervous system (AKA the fight or flight response).

Listen: Dr. Ron Ehrlich’s Healthy Bite Episode: Understanding Stress. Post continues after audio.

How cortisol works

Cortisol can get a bad wrap as we commonly associate it in its excess amounts. However when produced at the right time and at optimal amounts it can be beneficial. It is an anti-inflammatory mediator, meaning in times of disease states it reduces the impact of inflammation and helps the body feel less stiff, rigid or painful. Additionally cortisol can also aid in reducing the effect of insulin, meaning when at the right amount it helps burn body fat while keeping blood sugar levels stable.

It’s important to note that these effects occur when cortisol is produced at optimal levels. Unfortunately due to the nature of stress nowadays and people experiencing it over long periods of time (think weeks, months or even years) cortisol is rarely produced at optimal levels. When cortisol does function how it should its levels change throughout the day. It is high in the morning (approximately 6am), helping us get out of bed. It then begins to taper off until 10pm when it is at its lowest and helps us fall asleep, before rising again at 2am. Therefore when cortisol is functioning well it helps us achieve a good night’s sleep. However if we are in a state of stress, particularly the early stages of stress, cortisol doesn’t drop in the evenings but rather begins to spike again. This can be one reason for disrupted/poor sleep.

Excess amounts

Cortisol is the hormone that tells every cell in our body to fight for survival and that food is scarce. For this reason one of its effects is to slow down the metabolism and tell the body to store fat. This can leave you feeling lethargic and can be a cause for changes in weight during a stressful period. 

Additionally when levels are high and our fight or flight response is activated our digestion becomes suboptimal. As our body is alerted to signs of danger (whatever the stress may be) blood is diverted away from the gut and towards the arms and legs. This process prepares us for the possibility of having to sprint for our lives. The problem is if we consume food in a stressed state we are unable to properly digest it and absorb all the essential nutrients we need from it. Therefore even if you are eating the most nutritionally dense diet on earth, if you are eating when stressed you won’t benefit from it. Because what we eat provides us with the building blocks for growth, our cell health begins to diminish too.

Listen: Dr. Ron Ehrlich interviews Jacqueline Stone. Post continues after audio.

These are just some examples of how excess cortisol can impact our health. Research has also found that increased levels reduce the size of the hippocampus. The hippocampus is a small organ in the brain that regulates our mood and plays a role in memory. Additionally cortisol has also been found to reduce the effects of white blood cells. Meaning the immune system is weakened and you are more susceptible to infection.

I wanted to share this post to help lay the foundations for dealing with stress. I’ll be writing more on cortisol, its effects and how we can manage it in the coming months. I believe when we understand our bodies and how our choices impacts them, then we are better equipped to make good choices.

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