UNDERSTANDING
THE COMPLEXITY OF YOUR STRESS SYSTEMS
But what if you’re not stressed?
What if your work isn’t particularly high pressured, your relationships are good and you have plenty of money? Does that mean you’re fine?
Probably not. Unfortunately, many other aspects of our modern lifestyles cause symptoms similar to those of stress.
One example is our use of technology and artificial lighting. The brain is designed to use external cues (‘zeitgebers’ to use correct terminology) to set its own biological rhythms including the sleep-wake cycle (circadian rhythm).
This actually triggers the release of stress hormones at certain times of day. That’s because stress hormones are one of the tools that the body uses to wake itself up when you are sleeping. The release of stress hormones like cortisol and norepinephrine triggers activity in the brain that stirs you out of sleep and makes you fully alert.
But if the light is on at night, or you’re looking at your phone in the evening, this will cause the release of similar stress hormones right when you’re meant to be relaxing. That means you’ll continue to feel alert and won’t give your brain time to recover.
And what doesn’t help is the way that everything on the web and on TV is designed to grab our attention and pull us this way and that – this has been shown to cause effects similar to ADHD in the long term and make it harder for us to concentrate on any one thing for very long.
How Physiological Changes Trigger Stress
The above is an example of how stress is entirely a result of what’s going on in your life or even of what you’re thinking. Instead, stress can be a result of outside factors that physically influence you.
A way to think of it is like this:
Physical Sensations > Feelings > Emotions > Thoughts > Behaviors That is to say that your emotions are very often the result of physical things affecting your physiology.
For example, if you’re in a colder environment, this actually increases the amount of cortisol and the amount of norepinephrine. Physiologically, this is the same as low-level stress and that’s why a cold shower is a great way to wake yourself up!
This is also why being cold for too long can make you ill – as the stress response is suppressing your immune system.
Likewise, if you are hungry, then this triggers a physiological type of stress. Essentially, hunger causes your brain to release cortisol due to a decrease in blood sugar. When blood sugar is low, cortisol is released and the body responds to this as it would any other type of stress.
Why? Because as far as the body is concerned, this is a form of danger. If you are hungry, then you need to become active and get out there in order to seek out a source of food. Ghrelin, the hunger hormone, is released alongside cortisol and myostatin which breaks down tissue to provide energy.
When you eat on the other hand, this causes a sudden spike in your blood sugar. That in turn will cause you to release insulin, which absorbs the sugar for use around the body (either in the muscles and brain, or to be stored as fat).
This also has the effect of leaving behind another substance called ‘tryptophan’, which is found in most foods but doesn’t get absorbed. Tryptophan makes its way through the circulatory system all the way to the brain, where it crosses the blood brain barrier and converts to serotonin (as it is a ‘precursor’ to serotonin). Serotonin is the ‘feel good hormone’ and it’s also a precursor itself: this time to melatonin – the sleep hormone.
This is why when you eat a large meal, you tend to feel full, then happy, then sleepy. Christmas dinner ring any bells?
This is the opposite of the stress response. This is the aforementioned ‘rest and digest’ response.
And this is another cycle that your body goes through constantly: it moves from fight or flight, to rest and digest. You just don’t notice this because in a perfect world, that shift will be subtle and you won’t feel it too much. You just move slightly up and down the spectrum, becoming slightly more alert and focussed and then slightly less so.
Nevertheless though, this constant fluctuation does have an impact on things like your productivity and your mood. And it is also closely tied to the sleep-wake cycle. When you wake up for instance, you are in a fasted state having slept all night: thus you have high cortisol.