Q. I’ve heard that a fetus will respond to different foods in the mother’s diet. Can a fetus taste what its mother eats?
A. Research has shown that food experiences and preferences do, indeed, start in the womb. A fetus is exposed to the flavors and smells of its mother’s diet through the amniotic fluid that surrounds it. By the last trimester, the fetus is inhaling and swallowing large amounts of this fluid, and the sensory systems to detect taste and smell are already functioning. A mother’s diet can influence the smell and flavor of her amniotic fluid as well as her breast milk after the baby is born.
The development of food preferences in the womb was first shown in other mammals; rabbits whose mothers were fed juniper berries during pregnancy were more likely to forage for juniper after birth. Julie Mennella, a researcher at the Monell Chemical Senses Center in Philadelphia, has shown that the same phenomenon occurs in humans. In one study, 46 pregnant women were divided into three groups: One drank carrot juice during pregnancy and plain water after, one drank water and then carrot juice, and one group avoided carrot juice during the study period. When the babies began weaning to solid foods, researchers gave them the option of plain cereal or cereal mixed with carrot juice. Babies whose mothers had consumed carrot juice during pregnancy or while breastfeeding ate more of the carrot-flavored cereal and showed fewer negative facial responses to it.
Mennella says in-the-womb experience helps babies learn from their mothers which foods are available, desirable, and safe to eat. It provides yet another reason why eating a varied diet that includes plenty of fruits and vegetables is important during pregnancy and while breastfeeding. “When you eat these foods, you’re giving the child the opportunity to learn to like them,’’ she says. It’s also another reason to avoid alcohol and tobacco while pregnant - both can change the flavor of amniotic fluid, and Mennella has found that babies exposed to alcohol in the womb have a stronger preference for the scent of alcohol.
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