Julie Mennella, a researcher at the Monell Chemical Senses Center in Philadelphia, divided 46 women in the last trimester of pregnancy into three groups: One group drank carrot juice during pregnancy and water during lactation; one did the opposite; and one drank only water. Then, when the infants were about 6 months old and eating solid food, they were given cereal prepared either with water or with carrot juice. The babies exposed to carrot flavor either prenatally or in breast milk were much more enthusiastic about the carrot porridge than the plain mix; the other infants didn't show a preference, Mennella's team reported at a symposium of the American Psychological Society in Miami last month.

The researchers claim this is the "first experimental demonstration" that such early exposure affects taste preferences. The work indicates that breast feeding is better than formula, because it makes children more accepting of new foods, Mennella says. Breast feeding may also help all mammals teach infants what foods are safe--highlighting the importance of a healthful diet for pregnant and lactating moms.

The research also casts light on why people are so deeply attached to the foods of their culture, Mennella says. Linda Bartoshuk, a Yale psychophysicist who works on the genetics of taste and calls Mennella's study "wonderful work," agrees. Bartoshuk recalls that years ago some wives of foreign students at Brown University were greatly concerned about getting their usual cooking spices. "They had a strong belief that if they didn't eat the spices while carrying their child, the child wouldn't be properly introduced to the culture," she says. Now, Mennella's research suggests the young wives were right.