You probably already knew this, but chronic stress is bad for your health. It’s no thanks to the pandemic that many of us have given our trusty stress-management practices a backseat, replaced by even more of the cortisol-filled thoughts than before it started. That chronic stress we tried so hard to get rid of is back with a vengeance.
Being the health conscious folks that you are, you are likely already aware that chronic stress increases the risk of dementia. Like so many of us, you have seen friends and family succumb to it.
Not that many people know about the science behind the way in which stress causes damage to the brain. But once you do, it becomes easier to grasp the importance of making a conscious effort to reduce your stress levels, especially once you are over 50, pandemic or not.
So what is chronic stress? In essence, it’s when people are afraid, anxious, or angry all the time.
We now know a lot about how stress works in the brain. There’s a tiny little part of your brain, right on the inside, called the hypothalamus. It’s one fifth of an ounce of tissue, and I would say it’s a contender to be considered the most important fifth of an ounce in your body.
That’s because it is the part of the brain that controls your emotions. In addition to playing a role in various key things like our appetite and sex drive, it regulates anger and partly controls our fear response, two key aspects of that emotion we call stress. The hypothalamus funnels the stress response when something stressful happens to you.
But here’s the tricky thing about the hypothalamus: the fundamentals of how it conceives of and manages stress evolved thousands and thousands of years ago.
If you pick out any bunch of people at random from your neighbourhood or your country and ask them about which of their life experiences have been stressful, you’ll get a big variety of answers, but also a certain amount of overlap. What you won’t find is any of the things that made life stressful for our ancestors millions of years ago.
Back then, what caused stress – even if people almost certainly didn’t use that word for it! – was a lion in the underbrush. The hypothalamus’s stress response evolved to send people in that situation a pretty important message: you’d better do something about this quickly, or else you’ll die.
The eyes saw the lion, the brain processed that information, the hypothalamus sent an urgent warning message to the body, and the human ran a mile.
The last two of those steps happen through the production of hormones. The hypothalamus produces a hormone called CRH, which causes the pituitary to produce ACTH, which makes the Adrenal gland produce cortisol, a hormone that helps you to shunt the blood supply to your legs so you can run away faster.
At the same time, though, cortisol shuts off blood supply to your digestion, and it suppresses your immune system. Trading faster legs for slower digestion and less vigilance against disease is fine if there’s mortal danger to be dodged right now.
However, it’s bad news if your body is set to that mode permanently. And in the 21st century, the sorts of things that tend to trigger the stress response are much more constant presences in our lives.
If you don’t believe me, just go and look at the news feed on your favourite social network. Did you find anything that made you feel angry or afraid or stressed? Of course you did.
And that looming work deadline that you have, or that uncertainty over whether anyone is going to buy your house after it’s been on the market for nine months, or that weird mole on your arm that you swear wasn’t there before, or the question of how your kid is going to find a job when he finishes college: those and a million other 21st century things besides might be making you feel the same way.
If they are, then like your very distant, lion-fearing ancestor, you will first be releasing ACTH, and then cortisol. Because your ten-million-year-old hypothalamus still thinks that shunting blood to your legs is the best way to face these things that it is being told are dangers.
Once your stress response is up and running, your immune and digestive systems are now suppressed. And because of the types of things that make you stressed, they’re not suppressed once every now and then, but regularly. That’s not good, and it’s especially not good for your brain.
It’s not just a question of the knock-on effects that, according to recent scientific studies, poor digestion and a malfunctioning immune system can have on mental health. On top of those, if cortisol keeps feeding back into your brain, it becomes toxic and kills neurons.
More specifically, cortisol will kill neurons in the parts of the brain involved in learning and memory. And down that path lies cognitive decline, dementia and a plethora of other brain conditions that can make our final years an utter misery.
There’s a tempting way to respond to this alarming news about the damage stress causes to your brain: feeling yet more stress. But, please, take a deep breath and relax.
The good news is that cortisol wreaks this havoc very slowly. If you were able to enjoy reading this article, you still have time to learn to manage your stress and therefore keep your brain healthy. It’s just a question of embracing some simple lifestyle adjustments.
To help you track and manage your stress – plus various other habits that affect your brain health, including sleep, diet and physical exercise – you can check out the Synaptitude app. It won’t save you from lions, but it might just save you from cortisol.
Do you find yourself in constant stress these days? What do you usually worry about? Are you able to find respite from it? How? Please share with our community!