My mom loves to tell the story of how she had to have a chocolate ice cream soda every single day that she was pregnant with me. Whenever she tells the story, she can’t help but mention that this—months of prenatal exposure—must be why I love chocolate ice cream so much as an adult. The possibility that I might love ice cream simply because it’s delicious (and of course because everyone loves chocolate) has never crossed her mind. It has to be because she ate it so much when she was pregnant with me. Nutrition is obviously important for pregnant and breastfeeding women, and there is a large amount of research showing that a healthy diet promotes long-term brain and immune system development for the baby. But can babies taste what we eat while we’re pregnant? Can they taste our food via breast milk?
The idea that babies can taste what their mothers eat from inside the womb was dismissed as an old wives’ tale for years. It turns out that the old wives’ tale isn’t so far fetched after all. A fetus can taste and smell by the fifth month of pregnancy. By the seventh month, it can learn what tastes and smells are most familiar to them and actually develop preferences for those common tastes and smells by the time it’s born. For example, newborns of mothers who are fed foods that have the distinct taste of black licorice prefer that smell to other smells after they are born. Other infants (not surprisingly) are likely to turn away from this abrasive scent. Similarly, babies of mothers who eat a lot of carrot-flavored cereal while breastfeeding develop a preference for carrot-flavored cereal too, which other infants tend to reject. So both fetuses and babies that are nursing can in fact taste what their mothers eat, and can learn to prefer those familiar tastes rather quickly.
This might sound surprising and quite impressive in fact, but it isn’t anything that other animals don’t do too. Rats, for example, also learn to prefer familiar tastes and smells while in the womb, and are born with a preference for the smell of their own mothers’ amniotic fluid. This turns out to be an important behavior: Rats are born deaf and blind (they develop these senses later), so they need their mothers’ familiar smell to show them where to nurse. When a rat mother’s nipples are wiped clean after she gives birth, the rats don’t latch on; they simply don’t know where to go. So it looks like developing a preference for familiar tastes and smells early on—even before birth—might be an adaptive behavior that promotes survival.
For human babies, it isn’t clear that newborns maintain the preferences they develop while in the womb long term. There is some research that does show a relationship between foods consumed while breastfeeding and later fruit and vegetable preferences in preschool children, but these relationships might just reflect that mothers who eat lots of fruits and vegetables (when pregnant and beyond) also make their kids eat lots of fruits and vegetables. As some researchers point out, giving a fetus exposure to broccoli doesn’t mean they’ll happily eat it as toddlers. But, it is very possible that providing a foundation for babies to prefer certain foods while you’re pregnant and then reinforcing that preference by providing them with the very same foods after they are born might indeed solidify these early tastes. Based on this information, expecting mothers could potentially eat foods rich in culturally specific spices, like curry, to provide their babies with a head start in appreciating their unique cultural heritage.
When I was pregnant with my son Edwin, I not only ate foods that are part of my own cultural cuisine (Italian and Cuban flavors), but I also ate pretty much everything…all the time…for the entire 9 months. So, if all of this research turns out to be true, my son Edwin is going to love food…all of it…all the time. This might help explain why he is 85th percentile in weight and absolutely huge. On one hand, I’m glad that I exposed him to a wide variety of foods when I was pregnant—including chocolate ice cream of course—and I hope that this early exposure has provided him with a foundation to appreciate lots of different kinds of flavors. On the other, I can’t help but regret succumbing to all of those hot dog and potato chip cravings; I hope they don’t come back to bite Edwin in the stomach.