Gone are the days when starvation claimed significant numbers of people; and levels of societal violence are far below their historical peaks. Infection likewise has been largely tamed as a cause of death with the advent of antibiotics and good medical care.
It is far more likely these days that excessive comfort will be the cause of our illness and death.
We spend too much time sitting and engage in too little incidental exercise – that achieved in activities not specifically focused on getting fitter. We eat foods that are manufactured to provide immediate pleasure, with high levels of salt, fat, and sugar, consuming these in poisonous quantities.
Even the enjoyable and comforting pursuit of watching movies, shows and streaming services can be problematic, interfering with our sleep and therefore our health.
There is an increasing awareness of this issue, and a call among some experts to deliberately put our bodies (and brains) under pressure.
The logic behind this is that we have a remarkable capacity to adapt and improve but will only do so if we feel it is necessary. Whether this is efficiency or laziness, is subject to debate though the outcome is the same – a body and brain that is not challenged will lose its function and therefore suffer.
There is a limit of course – too much pressure and the system will break. With the right amount of regular stress, however, our bodies will become more proficient and capable. This “what doesn’t kill you makes you stronger” idea is also known as hormesis and the things we use to induce this adaptive change are known as hormetic stressors.
So, what are some examples of hormesis? Well, some are perhaps obvious. Exercise, for instance, clearly puts our body under stress, and no-one would argue against the health benefits of regular moderate physical activity.
But some are less immediately apparent. Cold therapy, for instance, puts the body under pressure as it tries to maintain its core temperature.
Immersing yourself in cold water for an adequate period has been shown to result in the release of cold shock proteins. These proteins seem to have a neuroprotective effect, maintaining and mending nerve cells and their connections.
At the other end of things, controlled exposure to heat also seems to have benefits: regular sauna use has been associated with a reduced risk of dementia, even considering the other healthful behaviours that sauna-goers tend to engage in.
Another hormetic stressor is fasting. The body senses that it may be under threat as nutrients are scarce and this leads to a cascade of helpful physiological changes. The health benefits of fasting for both body and brain are substantial.
Whether you intend to fast or experiment with cold or hot therapy, however, you should discuss your personal circumstances with your doctor.
There is even a school of thought – though not without its controversy – that part of the reason that eating plants and vegetables is good for you is because they release toxins as a defence mechanism when they are stressed i.e. torn or broken apart.
As they are consumed, these toxins act as a hormetic stressor – the body must deal with them, and in doing so becomes stronger.
Proponents of this view even suggest tearing up your leafy greens for instance, some time before you intend to eat them, to give them the opportunity to release more of these toxins.
Whatever you choose to do with your life, it is wise to consider whether you are too comfortable.
Kailas Roberts is a psychogeriatrician and author of Mind your brain The Essential Australian Guide to Dementia now available at all good bookstores and online. Visit yourbraininmind.com or uqp.com.au