Young children are more likely to react positively to the scent of vegetables if they were regularly exposed to them while still in the womb, new research has revealed. A long-running study meticulously recorded and analysed the reactions of three-year-olds to the smells of carrots and leafy kale, investigating how prenatal exposure might shape their later preferences.
Experts followed up on two earlier studies involving foetuses and newborns whose mothers had consumed carrot or kale capsules during the later stages of pregnancy.
The research, spearheaded by Durham University, found that three-year-olds whose mothers had taken carrot powder capsules during pregnancy displayed less negative reactions to the smell of carrots. Similarly, those whose mothers had consumed kale powder capsules while pregnant reacted more favourably to the scent of kale.
These extended findings suggest that young children retain a memory of the flavour and odour of foods they encountered in late pregnancy. Professor Nadja Reissland, from Durham University’s department of psychology, commented: “Looking at the children’s reactions aged three, you can see it’s a genuine response, they are not acting.”
The initial stages of the study involved researchers using ultrasound scans to observe the facial expressions of foetuses at 32 and 36 weeks, with further observations made around three weeks after birth.
Professor Reissland explained: “Each time, we coded their facial expressions when exposed to either the carrot or kale flavour or smell. What we see over time is that the children are still more favourable to the vegetables they were exposed to while they were in the womb. From this, we can suggest that being exposed to a particular flavour in late pregnancy can result in long-lasting flavour or odour memory in children, potentially shaping their food preferences years after birth.”
In light of these findings, Professor Reissland recommended that mothers-to-be maintain a rich, varied diet incorporating fruits and vegetables of diverse colours.
The researchers acknowledged the study’s small sample size, which involved following up on 12 three-year-olds from the larger cohort of foetuses and newborns. The children were presented with wet cotton swabs infused with either carrot or kale powder and filmed as they smelled them, though they did not taste the powders.
Their facial reactions were then monitored and compared with previous observations.
Dr Beyza Ustun-Elayan, a co-author from Cambridge University and Radboud University Medical Centre, highlighted the broader implications: “These findings open up new ways of thinking about early dietary interventions, suggesting that flavours from the maternal diet during pregnancy may quietly shape children’s responses to foods years later.”
The research received funding from Aston University and has been published in the journal Developmental Psychobiology.