Spend enough time breast-feeding a new baby and that age-old question will likely pop up: Can what a mother eats affect the taste of her breast milk?
Curious as to what infants can taste and when, scientists in Denmark fed various flavor capsules to 18 lactating women. They then took several milk samples throughout the day and found that what mom eats can flavor breast milk for up to 8 hours.
Licorice flavor peaked strongly in breast milk two hours after the capsule, as did the caraway seed flavor. Mint appeared in the mom's milk at lower concentrations but peaked much later, at six hours after ingestion. Researchers tried a banana flavor, but concentrations of banana never came through in the breast milk.
Besides looking for how a mother's diet can affect the taste of her breast milk, the authors of the study were also looking for evidence that flavors transferred to breast milk can influence the child's food preferences later in life.
"During infancy and childhood, individuals are very receptive to sensory and cognitive learning, and the behaviors established in this period are most probably important for later preference and food behaviors," wrote lead author Helene Hausner in the article, which is published in Physiology & Behavior.
"It's sweet. The one time I tried it, it was maple syrupy, but not overly sweet," said Morgan Kennedy Henderson, 43, of Wellesley, Mass. about her breast milk.
Henderson, a mother of two, says she wasn't too conscious of what she ate while breast-feeding, but has noticed a difference in the preferences of children who breast-feed.
"Babies who are breast-fed tend to have a more adventurous palate when they start eating solids," Henderson said. "Both [of her children] have been pretty adventurous, both were willing to try things really early on."
Karen Sussman-Karten, 48, of Newton, Mass., noticed her three children nursed differently when she ate certain foods. When she ate garlic, for example, they drank more. She feels a bit sorry for children who drink only formula.
"We wouldn't want to have the same food tasting the same way day in and day out," Sussman-Karten said.
The Danish scientists acknowledge that studies on breast milk flavor are obscure and rare, but some pediatricians and breast-feeding advocates insist that flavors in breast milk go beyond a simple enjoyment for the infant -- it might be important for health too.
"The fact that the flavor is passed to the milk is known," said Nicolas Stettler, assistant professor of pediatrics and epidemiology at the Children's Hospital of Philadelphia. He believes that more studies on the link between mothers' breast milk and the child's future eating habits could be interesting and potentially influential to the future of pediatric care.
"They did a study where they randomly assigned pregnant woman to drinking carrot juice, or not drinking carrot juice," he said. Babies who were exposed to the carrot juice flavor in milk were more likely to eat carrots as solid foods.
"I think it would be really interesting to have more specific knowledge of when exposure to those tastes is really important," said Stettler. "Parents should be mindful so they can expose the baby to a variety of foods. You know how it's always a struggle with young children to eat new food."
Breast-feeding advocate and professor Miriam Labbok has different advice if more studies confirm the link between food preferences and flavors in breast milk.
"Generally speaking, that's why we have always thought that babies have preferred cuisines of their culture," said Labbok, who is also the director of the Center for Infant and Young Child Feeding and Care at the University of North Carolina at Chapel Hill.
"In a way, it confirms, that when you begin adding in solid foods, that the family foods are better," said Labbok. "What the mother takes in, the child experiences, it's one more way for the child to become part of the family."
Labbok has never seen any studies on breast milk and flavors, but she certainly has heard anecdotes about it. "I think that's kind of neat," she said. "You always hear these old wives' tales; well these old wives are pretty smart."
Radha Chitale from the ABC News Medical Unit contributed to this report.