Prenatal Vegetable Exposure Linked to Reduced Negative Reactions in Three-Year-Olds

Young children react more favourably to the smell of vegetables if they were regularly exposed to them in the womb, researchers have found. A long-running study recorded and analysed the reactions of three-year-olds to the smells of carrots and leafy kale.

The research investigated how prenatal exposure might shape later preferences. It 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 study 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.

“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. Further observations were made around three weeks after birth. Each time, researchers coded the facial expressions when the children were exposed to either the carrot or kale flavour or smell.

Researchers stated that the children are still more favourable to the vegetables they were exposed to while they were in the womb. The findings indicate that being exposed to a particular flavour in late pregnancy can result in long-lasting flavour or odour memory in children.

This memory potentially shapes food preferences years after birth. The researchers recommended that mothers-to-be maintain a rich, varied diet incorporating fruits and vegetables of diverse colours. The study involved a small sample size, 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 monitored and compared with previous observations. A co-author highlighted that these findings open up new ways of thinking about early dietary interventions.

The research received funding from Aston University and has been published in the journal Developmental Psychobiology.