A study conducted by Durham University in England now provides a rare insight into how fetuses react to tastes in real time.
Around 100 women participated in the study by consuming either kale or carrots.
If we interpret the ultrasound images correctly, it can look like only one of the vegetables was to the taste.
The pictures showed that the fetuses scowled after the mothers ate kale, but smiled when carrots were on the menu, according to NBC.
– We are the first who can actually see the facial expressions of children compared to the food their mother has just eaten, said Nadja Reissland, co-author of the study.
The researchers gave participants capsules containing powdered versions of the two vegetables.
35 women consumed a capsule of carrot, and 34 women consumed the equivalent of 100 grams of chopped kale. The remaining 30 women consumed neither.
Twenty minutes later, ultrasound images showed that most of the fetuses exposed to the taste of kale appeared to be grimacing, while several who were given a taste of carrot looked happy and content.
All the women who participated were 32 to 36 weeks pregnant.
Experts also believe that what mothers eat during pregnancy can influence their child’s taste preferences after birth.
Previous research has shown that amniotic fluid can smell and taste differently depending on a pregnant person’s diet.
A 2001 study also found that infants who were exposed to the taste of carrots through amniotic fluid or breast milk were more positive about carrot-flavored cereal than infants who had not had the previous exposures.
However, the study only examined infants’ responses outside the womb.