Any flourishing corporation must change with the times. Your brain functions just like such a corporation. It moulds itself to your circumstance, so that you thrive. It switches its gears smoothly, gliding from one mode to another, in response to a changing terrain. Acute stress puts you into a unique paradigm. Intuition guides your behaviour and accentuates your sense of threat. Your emotions are amplified and motivation surges as your hormones give your brain a sugar surplus. In mice, acute stress boosts the growth of brain cells in the hippocampus, a site that serves memory and learning. This response mobilises all your resources and equips you for survival. Acute stress, in itself, is no bad thing. It temporarily turns you into a superhero version of yourself and can save your life. Who needs stress? We all do. Here’s why The benefits of acute stress transmute into the harm of chronic stress when the brain struggles to change its gears. When your stressful moment is past, you must, like an elastic band, snap back to a non-stressed state. If your brain is pushed past its elastic limit, however, it loses its resilience and finds it difficult to recoil from its stress paradigm. In chronic stress, the brain starts leaning towards a chaotic exaggeration of the state of acute stress. Mice who have suffered from chronic stress develop insulin resistance. Their hippocampi shrink. Humans suffer too. A Japanese study published in the Journal of Occupational Health last November, has shown how the chronic stress of diminishing supervisor support at work increases the risk of having insulin resistance. People with chronic work-related stress and burnout are demonstrably less able to regulate their negative emotions. Mice who are forced to endure stress over a period of time lose the ability to enjoy pleasure. These behaviours feed into themselves and reinforce each other. Dysregulated emotions can exaggerate acute stress into chronic stress, which further worsens emotional regulation, which in turn promotes chronic stress. Chronic stress may increase the risk of insulin resistance, which may lead to inflammation which can worsen symptoms of stress-induced depression. A powerful game changer in the stress landscape has been the discovery that chronic stress is associated with changes in brain structure. If we were to scan the brains of people with work-related stress and burnout we would be likely to find thinning in regions of the cortex that overlap with areas serving executive function, cognitive control, emotional regulation and attentional focus, the very functions that seem to suffer in chronic stress. The brain changes seen in chronic stress are startlingly similar to the changes seen in ageing and dementia, prompting some to question whether both of these conditions can be accelerated by a lifetime of chronic stress. A team from Sweden’s Karolinska Institute has recently shown how some of these changes can be reversed if people suffering from exhaustion related to chronic work-related stress undergo effective cognitive therapy and recover. The results, published in the January 2017 edition of the journal Cerebral Cortex , have tremendous implications because they give chronic stress a causal role in the brain changes, since these are reversed upon relief from chronic stress. It means that anything that you do to effectively buffer chronic stress will have a profound effect on your brain – an effect that goes beyond subjective sensations of wellness. It may also potentially reduce the risk of accelerated ageing, and even the risk of dementia. A successful attempt at restoring the brain’s function will not just bring benefits to emotional regulation and cognitive performance. Given the way in which the brain orchestrates the stress response and sets off a wide array of reactions, it may potentially have far-reaching consequences on processes as diverse as insulin dynamics and immune system regulation. What can be done to reverse or even prevent the effects of chronic stress? Emerging studies from the realm of dementia research suggest that for the brain, a multifaceted approach may work best. Many small changes instigated in concert may prove far more powerful than one big change made alone. Here are two examples of the large effect accrued from minor tweaks to lifestyle. Consider exercise. If you were to exercise in the morning, then your autonomic nervous system would generate more parasympathetic activity while you sleep at night. Chronic stress is associated with a shift away from parasympathetic activity, so this would be a smart move against chronic stress. According to a study from the Hokkaido University School of Medicine, published in November 2015 has shown that swapping evening exercise for morning exercise may also increase rapid eye movement (REM) sleep at night by about 10 per cent. REM sleep may play a role in learning to let go of fearful memories. If you are exercising late in the evening on most days, the melatonin you are producing at night will be less than the melatonin you would produce if you exercised in the morning. Melatonin production affects your circadian rhythm. Changes in circadian rhythmicity can contribute to stress-induced depression and can affect reward pathways. Your circadian rhythm also interacts with the bacteria that sit in your gut. An imbalance in gut bacteria has been associated with stress and anxiety and even with insulin resistance. Restoring healthy bacteria has been shown to help with stress. You see how the simple move to change exercise time from evening to morning can lead to significant and diverse positive consequences that may bolster your recovery from a stressful day. Consider alcohol. When rats are given increasing amounts of alcohol, they develop a weakness in the walls of their intestines. If you develop cracks in the intestinal wall, components of gram-negative bacteria residing in your gut can leak into your body and trigger inflammation. Chronic stress and depression are associated with inflammation. Making a mouse inflamed brings on depression. In this way, alcohol may amplify the effect of chronic stress. Giving the rats oats, however, mitigates this effect of alcohol on their intestines. Eating dietary fibre is inversely associated with levels of the stress hormone cortisol in humans. ‘Happiest man in the world’ has a tip for Hongkongers on how to be less stressed out There are many more ways in which you can address lifestyle, diet and behaviour, to make a significant impact on stress. Isolated, small interventions can work, but the narrower your approach, the bigger the change needed. For instance, if you have chaotic sleeping habits and a poor diet, and you only use yoga for stress relief, then you might need to practise intensely every day to feel significant relief. On the other hand, if you were to couple your yoga with a wiser diet and regulated melatonin, you may see positive results with less intensive practice. Our urbanised, technologically driven world has thrown our evolved behaviours into disarray. Globalisation synchronises global behaviour ignoring time zones and circadian rhythmicity. Technology speeds up productivity, obfuscating the line between work and play. The environmental cues we have evolved to respond to are blurred in concrete jungles lit by artificial light. You can’t change the world. You can, however, make many small but strategic adjustments to your day, and be stress-proof, within it. Mithu Storoni is a physician and researcher. Before moving to Hong Kong, she was a Clinical Research Fellow at the National Hospital of Neurology and Neurosurgery in London. She is author of Stress-Proof , published by Tarcher Perigree, an imprint of Penguin Random House, available August 2017