There's just one problem here. Nursing mothers are not human Vitamixes. It's not as though our kale salads become green smoothies for our babies. In general, your nursing baby is not eating what you eat. Your baby is eating breast milk derived from your blood, which carries the parts of your broken-down food that passed into your bloodstream.
If you eat a piece of bread, it's not going to straight to your baby because before it passes into your bloodstream, it needs to be broken down by various processes. By the time it has been broken down into smaller sugars, proteins, fats, and vitamins, all of which are combined with other sugars, proteins, fats, and vitamins to produce breast milk, that bread won't be bread-like at all.
But other molecules are much smaller and need less digestion before they can pass into the bloodstream. Read on to learn more about what can pass into breast milk, or scroll to the end for a quick quiz about whether or not a particular food is okay to eat while breastfeeding.
It's misleading to say that the baby eats what you eat. But it might be reasonable to say that your baby smells what you smell. The molecules that make smelly foods so pungent are tiny enough that they pass into your bloodstream without having to be fully digested.
The sulfur compounds contained in garlic are so powerful that they don't even have to be eaten in order to be tasted. Garlic can be absorbed through the skin and actually be tasted later, even when applied to the feet. Even chopping garlic with your bare hands can change the flavor of your milk.
Your baby isn't eating garlic, which will have to be digested into smaller parts before it makes its way into your milk. Your baby is, however, eating some of the small molecules that make the smell of garlic. That flavor change is not a problem for most babies. Some studies have shown babies will actually drink longer once introduced to garlic.
This may help explain the commonly shared but scientifically dubious claim that garlic increases milk production. There is ample evidence that babies feed longer when introduced to new flavors like garlic. That increased feeding time might, in turn, stimulate more milk production. In other words, it wouldn't be the garlic increasing the milk production, but the curious young eater enjoying a new flavor.
In the garlic study, babies' prolonged feedings tapered off after they got used to the garlic flavor. That was also true in similar studies of the less pungent but still strongly scented vanilla. There's little evidence that any one flavor will lead to prolonged nursing or to increased milk production. But these studies suggest that if mothers eat a wide variety of foods, their babies may nurse longer to keep trying new flavors.
What about foods that are less smelly and more spicy? Are hot peppers, ginger, and cinnamon safe for babies?
Given the ubiquity of hot peppers in cuisines all over the world, it's hardly surprising news that hot peppers are generally safe to eat when nursing. There is one 1996 case study of two babies who experienced dermatitis after their mothers consumed red peppers. Although the condition sounds terrifying, "dermatitis" just means "skin inflammation," a symptom not uncommon in adults who enjoy hot peppers. The case study did not report the babies experiencing any pain and their dermatitis resolved on its own in a few days.
That case study should not scare you away from extra jalapeños on your next breakfast burrito. Instead, that study just suggests that the molecule that makes many hot peppers hot – capsaicin – is passed through breast milk.
As far as spices go, eat whatever you can tolerate. It's not like you're asking your baby to take the cinnamon challenge. Even when all of those "hot" molecules pass into your breast milk, they're not going in there alone. Considering that many curries consist of a blend of spices and milk, your child is essentially consuming his first curry. At least one study has suggested that nursing mothers' diets are a significant contributor to national and cultural cuisines, as children show preference to flavors introduced during pregnancy and nursing.
Before we leave the topic of spicy foods, we should also take a look at one more set of spices: those recommended to women for increasing their lactation.
Breastfeeding women looking to increase their milk supplies are encouraged to ingest a variety of herbs and spices. According to LactMed, a database maintained by National Institutes of Health that keeps up-to-date information on drugs that pass into breast milk, it's unclear whether or not the contents of your spice cabinet will increase milk production. Many strong flavored herbs, among them anise and fennel, are claimed to increase milk production but there are no strong trials behind those claims.
These spices can, however, change the flavor of breast milk and, given what we know about babies who nurse longer after being introduced to a new flavor like garlic or vanilla, it's reasonable to guess that babies nurse longer when exposed to strong-smelling herbs. Perhaps this is why fenugreek has long been claimed as an herbal remedy for increasing milk production. It may not stimulate milk production on its own, but your baby may be interested in the maple syrup aroma it adds to your milk.
Given the basic logic of human digestion, we understand that if you eat a peanut, your baby isn't eating that peanut through breastmilk. But your baby may be eating one of the distinct proteins found in peanuts.
The peanut proteins that most commonly cause allergic reactions, as well as proteins at the root of cow's milk and egg allergies, are excreted into breast milk. Does this mean that you should avoid these foods? In most cases, no. According to the recent LEAP trial, early exposure to peanuts actually reduced the likelihood of serious allergies, so for most women there's no reason not to eat peanuts. In fact, there's some suggestion that eating peanuts will lessen your child's risk of developing a peanut allergy.
It's possible that your baby will be allergic to something you eat. But the only way to find that out is to eat a food and induce a reaction. So, in most cases, you don't need to avoid any foods for fear of allergies unless, of course, you are allergic to those foods.
Do you like it? Then eat it. If not, then don't eat it.
If you're trying new foods for the sake of giving your baby more variety and a sense of gustatory adventure, good for you! You don't have to repeat any foods you don't like because chances are, given what we know about garlic, vanilla, and other similarly aromatic foods, your baby would get bored if you kept eating them anyway.
Does your baby like it? Irrelevant. Many parents claim that their babies frown or push away from the breast because Mom consumed broccoli or dark chocolate or hoppy beer. But if most parents can't figure out what's making our babies cry for hours in the middle of the night, perhaps we place too much weight on our assessments of babies' milk preferences. Looking to your baby for breast milk tasting notes is unlikely to yield good information on what he or she likes or does not like.
It takes a village!
Join ours. Before we were parents, we were people. Sign up for tips and stories from parents who get it.