Parenthood ‘inoculates’ adults against disgust, study finds

Repeated exposure to bodily waste appears to lower disgust in parents, with effects that persist beyond infancy, a study of 99 parents and 50 non-parents suggests.

The study used parent-specific questions and child-related stimuli, including images of soiled nappies, and tracked reactions such as looking away.

Non-parents strongly avoided images of bodily waste.

Parents showed a different pattern once their children had started eating solid food, with little to no behavioural avoidance of soiled nappies or general bodily effluvia (bodily fluids and waste).

The reduced response generalised beyond child-related stimuli.

By contrast, parents whose youngest children were still exclusively milk-fed showed avoidance levels similar to non-parents, even if they had older children.

This suggests responses may remain heightened during early infancy, when babies are most vulnerable to illness.

Researchers at the University of Bristol say the pattern may reflect an adaptive response: stronger disgust early on could reduce disease risk for young infants, while later desensitisation enables parents to manage illness care more effectively.

Dr Edwin Dalmaijer is a cognitive neuroscientist in Bristol’s School of Psychological Science and a lead author.

He said: “Parents of young children are bombarded with grossness from day one, from dirty nappies to sick and snotty noses.

“Our findings provide strong evidence that long-term desensitisation to disgust does occur.

“After the sensitive early months of infancy, continuous exposure to children’s bodily effluvia appears to ‘inoculate’ parents against disgust, reshaping a deeply ingrained emotional response that is otherwise difficult to change.”

The researchers said the findings could inform training for roles that require managing such responses, including nursing care and other jobs involving regular contact with unpleasant substances.

Dalmaijer said: “Parenthood doesn’t just change daily routines, it can fundamentally alter how humans experience disgust, with lasting effects that extend beyond childcare itself.”