Science Writing, September 22 (EFE).- The facial expressions of a group of unborn babies, captured by 4D ultrasound, are the first direct evidence for a group of scientists that the fetus reacts to the taste of food eaten by the mother.
The team, led by the University of Durham (UK), performed ultrasound scans of more than 100 pregnant women to see how the fetuses reacted to the taste of carrots or ink immediately after the mothers ate them.
Fetuses exposed to carrots showed more “smile face” reactions, while fetuses exposed to kale showed more “cry face” reactions.
The authors, who published their findings in Psychological Science, believe they can further our understanding of the development of taste and smell receptors in humans, and suggest that what pregnant women eat can affect the taste preferences of babies after birth.
Humans experience taste through the combination of taste and smell. In the fetus, it is thought that it can inhale and swallow the amniotic fluid of the womb.
By observing the fetal facial response “we can hypothesize that a series of chemical stimuli pass through the maternal diet into the fetal environment”, according to Benoist Schall, from the University of Burgundy (France), one of the signatories.
The team, led by Durham University’s Beija Ustun, said, “It’s amazing to see unborn babies reacting to the taste of kale or carrots during scans and sharing those moments with their parents.”
The study group consisted of women aged 18 to 40 at 32 and 36 weeks of pregnancy, who received a capsule containing approximately 400 mg of carrot or ink powder about 20 minutes before each scan.
Participants were not allowed to eat any food or flavored drinks for an hour before the scan, and they did not eat anything with carrots or kale that day to control for factors that could affect fetal response.
The response observed in both flavor groups, compared with fetuses in a control group who were not exposed to either flavor, showed that exposure to small amounts of carrot or kale odors “was sufficient to stimulate a response,” the university said.
According to Nadja Reisland, another author of the study, the research “may have important implications for understanding the first evidence of the ability of fetuses to perceive and discriminate the different tastes and smells of foods eaten by their mothers”.
The researchers said their findings could help inform mothers about the importance of taste and healthy eating during pregnancy.