Dr Michelle Dickinson: nanotechnologist on how parenthood can inoculate people from disgust

From dirty blowouts to spit-up and stomach bugs, parents quickly learn that unpleasant messes are part of everyday life.   Now, new research published in the Scandinavian Journal of Psychology suggests that this constant exposure doesn’t just test patience - it actually permanently changes how the brain responds to disgust.  The study found that long-term exposure to bodily waste significantly reduces parents’ disgust reactions, and that this effect can last well beyond the childcare years. The findings, shed new light on how caregiving reshapes the brain and may have implications for professions where managing disgust is part of the job.  Disgust is a basic human emotion that evolved to protect us from disease. The familiar 'yuck' response triggered by spoiled food, dirty environments or bodily fluids helps keep us away from potential sources of illness. It’s not just psychological, the body often reacts automatically, with nausea or an urge to move away.  What scientists have long debated is whether repeated exposure over months or years can truly dull this reaction. Parenthood offered a natural test case.  The researchers studied 99 parents and 50 non-parents, analysing both questionnaire responses and observable behaviour, such as how much participants looked away from unpleasant images. The study included parent-specific scenarios and visuals, including pictures of heavily soiled nappies.  As expected, non-parents showed strong avoidance when viewing images of bodily waste. Parents, however, reacted very differently, but only once their children had begun eating solid food.  Parents of weaning or weaned children showed little to no avoidance of soiled nappies or even other forms of bodily waste. Their reactions suggested that prolonged, unavoidable exposure had desensitized them to disgust. Notably, this reduced response wasn’t limited to child-related messes; it extended to bodily waste more generally.  By contrast, parents whose youngest children were still exclusively milk-fed showed disgust responses similar to those of non-parents, even if they had older children. This surprised researchers and suggests that disgust may remain heightened during the earliest months of infancy, when babies are especially vulnerable to infection.  The researchers believe this pattern may reflect an evolutionary adaptation. Strong disgust early on could help protect fragile infants from disease, while later desensitization allows parents to provide hands-on care when children are older and more resilient including when they’re sick.  The study suggests that parenthood can fundamentally reshape how people experience a deeply ingrained emotion. Researchers say these insights could help inform strategies to support healthcare workers, caregivers and others whose jobs require regular contact with unpleasant substances.  LISTEN ABOVESee omnystudio.com/listener for privacy information.