While too much stress can negatively impact your health, a little bit of stress can actually be good for us. A 2012 study by Stanford University School of Medicine scientist Firdaus Dhabhar, PhD, found that immune responsiveness is heightened by the “fight-or-flight” response.
This response is ingrained in us from times we felt threatened by predators or natural events and needed our bodies to go into overdrive to protect us. Known as an acute stress response for its immediate effect that dissipates afterwards, our bodies undergo a release of stress hormones adrenaline (otherwise known as epinephrine) and cortisol into the bloodstream. Like the instant effect a can of spinach has on Popeye, this causes us to temporarily turn on superhero mode: our heart rate and blood pressure increases; our memory becomes sharper; our concentration, strength and ability to react increases; and our immune system becomes stimulated.
During this, blood levels of cells called cytokines increase to promote inflammation in the bodypro-inflammatory cytokines increase. Inflammation is a necessary short-term response for eliminating pathogens to protect against infection and initiate healing. Dhabhar’s study found that the fight-or-flight response triggered a pattern of changes in blood levels of the three major stress hormones norepinephrine, epinephrine and corticosterone (the rat equivalent of cortisol), along with the movement of immune cells from reservoirs such as the spleen and bone marrow into the blood and to various “front line” organs.
The role of these hormones was shown to be vital: norepinephrine prompted the movement of all our major immune-cell types; epinephrine sent infection-defending white blood cells known as lymphocytes to destinations like skin; and corticosterone caused virtually all immune cell types to head out of circulation to prepare for attack. As Dhabhar puts it, “Mother Nature gave us the fight-or-flight stress response to help us, not to kill us”.
The phrase ‘everything in moderation’ comes into play, as regularly experiencing this intense response can manifest into chronic stress. A research team led by Carnegie Mellon University's Sheldon Cohen employed psychoneuroimmunology, the study of the effect of the mind on health and resistance to disease, to find that chronic psychological stress is linked to the body losing its ability to regulate the inflammatory response. The research showed that the effects of psychological stress on the body's ability to regulate inflammation can cause the development and progression of disease. "Inflammation is partly regulated by the hormone cortisol and when cortisol is not allowed to serve this function, inflammation can get out of control," said Cohen, the Robert E. Doherty Professor of Psychology within CMU's Dietrich College of Humanities and Social Sciences.
So how can we help counteract regularly stressful situations to keep our immune system strong? The answer may lie in none other than laughter, since a study showed that laughter significantly reduces levels of inflammation-triggering cytokines in people with rheumatoid arthritis. Laughter has also been shown to decrease the level of stress hormones cortisol and epinephrine.
It’s a form of alternative therapy Norman Cousins explored with his physician to supplement his vitamin C intake when he was diagnosed with ankylosing spondylitis (a degenerative disease causing the breakdown of collagen), to remarkably effective results, prompting a string of research projects since.Despite lockdown limitations, laughter can be practised with anything from online laughter yoga (now a recognised movement in wellbeing) to watching a comedy show on Netflix. So next time you’re wondering how to reduce your stress levels, try finding humour where you can—it might just change your life. And if it doesn’t? At least you’ll have a good laugh about it.