Bad habits’ hidden impact
Unhealthy habits such as smoking, drinking or overeating not only cause their own physical damage but also spark changes that release harmful stress hormones.
Researchers from James Cook University have found that using these coping mechanisms to deal with mental stress caused by life pressures is a Catch-22 situation – as it then opens up molecular pathways that produce more mental stress.
Professor Zoltan Sarnyai from JCU’s Centre for Molecular Therapeutics led the study. He says the researchers systematically reviewed all published work that measured ‘allostatic load’ associated with behaviours risky to health.
“Allostatic load is the biological measure of the long-term wear and tear on our body from stress.
It’s mostly measured by examining biomarkers associated with the neuroendocrine, cardiovascular, immune and metabolic systems,” said Professor Sarnyai.
The scientists found bad habits such as unhealthy eating, lack of exercise, smoking, and alcohol and drug use, along with bad sleeping habits, increased the allostatic load on the body individually and even more so in combination.
“It is not that smoking only affects your lungs, alcohol only damages your liver, and eating unhealthy food causes your waistline to increase,” said Dr Beena Suvarna - the first author of the study.
“These bad habits will influence our whole body by releasing stress hormones, affecting our metabolism and immune defence mechanisms. These will ultimately contribute to the chronic diseases that considerably shorten our life expectancy,” said Dr Suvarna.
She said the research highlights that toxic stress and health risk behaviours share biological pathways through which they exert detrimental effects on the body and the brain.
Dr Sarnyai said it’s particularly sad that health risk behaviours are strongly associated with the poor and marginalised and those subjected to traumatic life events.
“It’s a real Catch-22 situation. I am exposed to considerable stress and trauma, so I try to somehow survive and gain some pleasure out of life. I self-medicate with smoking, alcohol, eating cheap, high-fat/high-carb burgers while sitting in front of the TV.
“But in exchange for a very temporary relief of the mental pain I successfully manage to combine the worst biological consequences of chronic stress and an unhealthy lifestyle,” he said.
Professor Sarnyai said all hope is not lost for those with bad habits.
“Using what we call the allostatic load index, we should be able to predict the deterioration of physical and mental health before disease develops.
“And more importantly, we can now see even more clearly, with even more direct evidence,that if people exchange bad lifestyle habits for healthy ones they can break this vicious circle and live healthier and longer lives.”
Link to paper here.