True. You may have read that this is a myth, and I have come across many assurances that the flavor in the food a breastfeeding mother eats do not enter into the breast milk. However, we have plenty of evidence that individual flavors from the food a mother eats do indeed get into and alter the flavor of the breast milk itself. The question, then, is whether this will turn off baby and cause him or her to reject the milk.
First, we have evidence from dairy cows. If we feed dairy cows certain foliage with strong flavors, like silage, wild onions, or skunk cabbage (that sounds yucky), the flavors are detectable in the milk as early as 20 minutes after ingestion, and these flavors are at their most pronounced two hours later. Like cows, we are mammals, and the way breast milk is produced in humans is not that different than the way it is produced in cows, although the composition is different, in terms of individual proteins and their amounts. Certainly, we can assume that what is true for cows is true for humans, in this case. The evidence bears this out. So mom, if you eat garlic your breast milk will be garlic flavored. If you eat onions, your breast milk will be onion flavored. 1
The obvious question, then, is whether this is a bad thing or a good thing. As adults, we certainly don’t want milk (from cows) to taste like garlic or onions. God forbid it taste like skunk cabbage, because whatever that tastes like, it can’t be good. We expect it to taste like milk. Does baby expect mother’s milk to taste like mother’s milk? Will baby then refuse to suckle if you eat the wrong thing and introduce a disagreeable flavor into the milk?
Nope, this does not seem to be what happens. Babies don’t really have taste preferences yet and, contrary to what we might assume, strong flavors do not necessarily turn a baby off suckling. Mennella and Beauchamp, in 1991, examined the effects of garlic ingestion on breastfeeding behavior. Now, I would think that garlic flavored milk would surely be a little off-putting. But that is not what the investigators found. The babies, instead, suckled longer and obtained more milk when the milk had a garlic flavor!
Later, in 1996, they also tested vanilla. Now were onto something. Same result, the babies suckled longer. They also flavored formula with vanilla for bottle-fed babies and those babies fed longer, as well. However, they did not keep feeding longer over time when given vanilla flavored milk. What this suggests is that it is the change in flavor that stimulates baby to suckle longer and eat more, rather than the particular flavor. These same investigators, in other studies, suggested that formula feeding, always tasting the same, could represent a deficient sensory experience. They reported that breast fed babies were more accepting of solid food when they were introduced than formula fed ones. It could be that having milk with varied flavor facilitates the acceptance of new foods. And also, that when the baby has milk with various flavors, she is “learning” the flavors acceptable to mother, and this might cause her to be more likely to select appropriate foods later on.
In summary, the foods a breast-feeding mother eats do flavor the breast milk she produces. Infants are not displeased when new flavors enter the breast milk, but instead they are stimulated to suckle longer and ingest more milk. It is not the individual flavor in the breast milk that stimulates this behavior, but variety itself. Varied flavors in breast-milk, as opposed to monotonous flavor in formula, can make it easier to introduce solid food later on. And, finally, the particular flavors and infant is exposed to in breast milk can “teach” the baby to choose certain solid food when they are older. According to the evidence we have, breast-feeding mothers should eat a variety of healthy foods, to stimulate interest in their infant, and to encourage the acceptance of healthy solid foods when appropriate. 2
None of this, of course, proves that it is impossible for your baby to find certain flavors in your milk to be disagreeable. And, as well, certain foods might trigger GI discomfort. While you should feel encouragement to eat a variety of healthy, and even strongly flavored foods, if you notice that your baby always refuses to suckle after you eat a certain food, let your motherly wisdom prevail and avoid that food. Most likely, if it happens at all, it will not happen often, although we cannot say that all human babies are the same.
- Ensminger, Audrey H. Foods & Nutrition Encyclopedia. Boca Raton: CRC, 1994.
- Riordan, Jan, and Karen Wambach. Breastfeeding and Human Lactation. Sudbury, MA: Jones and Bartlett, 2010.