Episode 2: Nutrition While Breastfeeding: What Moms Need to Know for Infant Growth and Milk Quality

What you eat postpartum supports the breastfeeding parent more than breastmilk itself. Dr. Liz Daniels explains postpartum nutrition, breastmilk composition, and which nutrients truly matter for recovery and infant health.

Postpartum nutrition is often framed as a way to “optimize” breastmilk—but that framing creates unnecessary pressure for parents. In this episode of The Lunchbox Reformation, we break down what postpartum nutrition actually affects when breastfeeding, and what the body regulates automatically.

You’ll learn why breastmilk composition is far more resilient than social media suggests, how carbohydrates, fats, and protein support the parent more than the milk itself, and which micronutrients—like iron, vitamin D, iodine, choline, and omega-3s—deserve attention during postpartum recovery.

This episode is for anyone who is pregnant, breastfeeding, postpartum, or supporting a new parent and wants evidence-based clarity without fear-based feeding advice. The takeaway is simple but powerful: your body handles milk production—nutrition supports you while it does that work.

If this resonates with you, please subscribe and/or follow for more. I would love your feedback - leave a comment and let me know what you think!

Register for the Breastmilk and Formula Masterclass here!

NEW COURSE! "Read the Pattern: Feeding Your Baby 0–4 Months" — because a healthy relationship with food starts earlier than most people think. Course Link!

Transcript

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The question shifts. Really, I think what we should be asking ourselves is instead of how do I make better milk, I think the question is really, what does my body need to stay supported while it's doing this work? And that's where the nutrition comes in. Welcome to the Lunchbox Reformation with Dr. Liz. This podcast is for folks who are craving better nutrition for their kids, but are tired of the whiplash of nutrition claims and diet culture influence. You're reading labels, paying attention to ingredients, but you still doubt yourself. And for good reason, food goes deep, and often we fear making costly mistakes that as parents we hope to prevent. If you're ready to explore the ins and outs of your child's actual nutrition needs and nourish the whole child from the inside out, hang with me, Dr. Liz Daniels. I'm a board-certified pediatrician plus registered dietitian, and we're going to dig deep into real deal nutrition science, honest talk about barriers to health, and real stories that I help address. So let's dig in. Hey, what's up, guys? Thanks so much for joining me today on the Lunchbox Reformation. I'm your host, Dr. Liz Daniels, board-certified pediatrician plus registered dietitian. And today we are going to talk about postpartum nutrition. Like if you are about to have a baby, if you're pregnant, if you know somebody who's pregnant, or you are you're in the early stages of breastfeeding. I just want to share this with you. Save this podcast for that time in your life, or share it with a friend, or if you have a loved one who is going to be having a baby, take note so you can support them really well. I am so excited to share this with you today because, really and truly, this is one of the most beautiful stages of life for most women when you experience it. And so I just want to leave you all with encouragement and confidence as you listen to this. So the majority of women think about entering postpartum breastfeeding. So then you also think about how your nutrition or what you do for your body is going to affect the baby. And that's kind of the central line that I want to talk about today. Like what you can do, what's within your control, and what's not. So, really, I think the key takeaway is that your body makes amazing milk, whether or not you are trying. Lactation isn't this like just super fragile thing. It's not something that you accidentally ruin with the wrong breakfast or if you miss your prenatal vitamin. Our bodies are so brilliant. And really, much of what makes breast milk what it is actually just happens automatically. You don't get to choose how much lactose it produces. You don't get to choose how much fat goes in there or how much protein goes in there. It happens because your body already does it. This is good news. Good news because it means your milk isn't just like hanging in the balance of your decisions, but it's also frustrating because there's so much postpartum nutrition advice that makes it sound like you should be able to control every detail. Like if you eat all these things, then you should produce more milk, or it'll make your fat even richer or better, just if you try hard enough. And the reality is you actually don't have that much control over what your milk is like. That's not failure. That's biology doing exactly what it's supposed to do. So today, what I want to go over is what you do have control over and what you don't, nutrient by nutrient. We're gonna separate that out and think about the parts of the milk production that your body handles totally beautifully, all on its own, and then the parts where your nutrition actually can play a role. And this is not to just perfect it, but to support you through the season so you can let some of the garbage go. Okay. So if you've ever been told by somebody that a specific food or beverage is gonna boost your milk supply overnight, or that you're going to ruin it by not eating X, Y, and Z, I just want you to know that those ideas really aren't supported by physiology. So once we understand that milk composition is really handled automatically by the body, the question shifts. Really, I think what we should be asking ourselves is instead of how do I make better milk, I think the question is really, what does my body need to stay supported while it's doing this work? And that's where the nutrition comes in. Really, not as tools to control your milk, but as fuel to sustain you as your body makes it on its own. So let's talk about that in more detail with carbohydrates, fats, and protein. So when we think about macronutrients, the first one I want to talk about is carbohydrates. Carbohydrates are going to be broken down in your body all the way down to the most simple form, glucose. And then once you have glucose in your bloodstream, the breast tissue will help make lactose. Lactose is the main carbohydrate that's in breast milk. And that's really energy source for the baby. And this has nothing to do with whether or not you eat lactose. What I'm saying is that your body is creating the lactose. Pretty cool. This happens totally automatically. And your body prioritizes this no matter what you eat. Like even if you aren't getting enough nutrition, your body is still going to make lactose. It's still going to produce that for your baby, even if your carbohydrate source is low. So what I mean here is that even if you have, say, one day you're having a ton of carbs, and then the next day you have barely any, your baby's milk is still going to have the same amount of lactose in it from that day to the next. It's pretty much the gonna be the same. Now, what matters? Why does it matter if you get, you know, lots of carbohydrates versus none at all? Well, because if you are underfueling the carbohydrate, your body is going to first prioritize making that nutrition for your baby. And then, second of all, if there's enough left over, it will make things for you. And if we have low blood sugar for ourselves, then you feel it. It ends up really affecting your energy level. And God knows, you're already tired enough feeding a baby. So going on a low-carb diet after having a baby really isn't ideal for you. Your breast milk is probably gonna stay the same, but you as a mama probably aren't gonna be fueling enough for your body to stay healthy and to stay well at its optimal place. The best sources for this really are gonna be in your whole grain breads, beans and lentils, oats and rice. And why do I bring this up? Because the other thing that's gonna be in the carbohydrate source, and this does translate over into diversity of the belt. So, like something you do have control over is the type of grain that you're eating. These are going to produce what we call human milk oligosaccharides. And if you're curious, we're gonna talk more about this in another one, but these are basically the prebiotics for your baby's gut health. And if you have a lot of different types of grains in your diet, then the likelihood of having a lot of different HMOs in your breast milk, which is basically the fiber in your baby's diet as they're nursing, is going to be more broad. And that does reflect the maternal diet. Again, not meal to meal, but over time. So, takeaway for the carbs. If you eat low carb, your baby's still gonna have lots of lactose in their diet. But the diversity of your carbohydrate source and getting enough for you to take care of your own body are essential for you to feel your best. Okay, let's move on to fats. So this one is really interesting because in the very beginning, breast milk is lower in fat, right, when you're having colostrum. And then by the end of the first month of life, that fat composition has doubled. And then it can even get higher throughout that first year of life, meaning that about 50% of your baby's calories are gonna come from fat from your breast milk, which is so important. And what's super cool, there's a whole nother conversation about this, but it's not just what kind of fat that makes this awesome. It's how it's packaged, it's how it's delivered. There's a lot there that's so amazing. But your body does this, again, even if you aren't fueling it properly. There are a lot of things that you can do to help support this, one of which is actually certain fatty acids like DHA, which is an omega-3 fatty acid. And the thing that I like to really kind of drive home here is that in this situation, eating a high fat diet doesn't mean that your baby's gonna get more fat. Your body produces what it's gonna produce. Even if you have a low-fat diet. So high fat to low fat, your your milk is still gonna be adequate fat for the baby. The difference is in the type of fats that it's going to be putting in the breast milk. And this is where, again, your diet can really enhance this. Um, and some women will tell me, oh, I just don't like fish or I don't like, you know, any of those things. And I like to remind families that one of my favorite sources of omega-3 fatty acids actually are in the plant sources as well. So flaxseed, chia seed, hemp seed, these are great sources of ALA that get converted over to DHA. Um, grass-fed eggs, grass-fed beefs actually can have some in there too. Avocado, olive oils, those are great sources of different types of lipids, of um unsaturated fatty acids, but really and truly, like it's the omega-3s that are really gonna be robust here. Now, if you really don't like that and you want to supplement, totally, totally fine. But just know that eating more fat doesn't mean you're gonna produce more milk. It doesn't mean that you're gonna produce fattier milk. It's the type of fats that you eat that will be represented in the breast milk. Okay, moving on to protein. And this one I think is really, really interesting. So, once again, what do you not control versus what can you control? Protein in your diet actually helps you more than it's gonna help the baby. Believe it or not, colostrum has a fair amount of protein per milliliter or per ounce compared to mature milk. But even still, for a single cup of breast milk, it only has about two grams of protein in it. It's really not much. So the the primary nutrition that the baby's getting is in fat and in carbohydrate with a little bit of protein. Now, the protein that's in there is really bioavailable. So it's going to be absorbed really beautifully. It serves very important roles and it's amazing and awesome. But there's not a ton of protein in the breast milk. So I'm gonna camp out here for a minute because our world right now is very protein-centric. Now, eating more protein is not going to make more protein in your breast milk. Okay. But it really is important for you for tissue repair, for your own immune function, and helping your blood sugar be nice and stable. So I do recommend a fair amount of protein in your diet postpartum. I think most people are aiming for this anyway, trying to get balanced meals. I think a lot of people are hearing the language of 25 grams of protein per meal. I think that's a great idea, good thing to aim for. But the idea here is really that the protein here is going to benefit you as the mama. We just want to be careful that it's not so heavy in protein that it is displacing carbohydrate or fat for you and your baby. Okay. So it doesn't need to be 50% of your diet. So typically, I'm going to encourage my mamas to get protein from foods over protein shakes or protein powders. And I think those are okay, but this is where I would just maybe say be thoughtful about your source of protein because there are some products that we're learning how to may have trace amounts of metals in them or other contaminants that you really don't want your baby getting. One of the best sources that's often overlooked, other than the cottage cheese frenzy that we're currently living in, are again, um, are beans, lentils, tofu, timpe, fish, chicken, Greek yogurt, eggs. And these would be awesome things to be able to have for both you and your partner. So if someone's wanting to make you guys some meals or throwing together a meal train, um, share this podcast with them so they know that what you're looking for is not just a lasagna, but to have something that offers really good diversity of the fats and protein um carbohydrate sources so that you can really support your own body as it's making this most amazing milk. So when we zoom out, the pattern really is so clear. Your body handles the milk composition. The macronutrients support you while it does the work to make your milk. The whole point here is not to control your diet or to try to control what's in your milk. It's about making sure that you have the capacity to make the best milk possible. So now I want to shift gears a little bit and just talk about a couple micronutrients that are really important to pay attention to. And you know this already if you've been looking at your prenatal vitamins, but iron, super important. Okay, so like in this particular scenario, I'm just gonna mention a couple of things. Iron is like the most common micronutrient deficiency in the world. And it's really common, especially in postpartum women. The last four weeks of pregnancy, um, the baby is actually getting sort of a placental shift of iron to help support them in their first few months of life. And that can end up being depleting to the mom. Also, sometimes there's postpartum hemorrhages or complications during delivery that lead to excessive blood loss. And then you also bleed after you have your baby. So there's a lot of opportunity for anemia to develop in mamas. And iron is a really important micronutrient, and you you need to get it through your diet. Sometimes it's also important to supplement. So this is where some personalization really comes into play. And making sure that you're talking with your OB or your um, you know, healthcare provider who's looking at your labs and making sure that you're getting restoration here because without it, it means that you won't be at your best. So one of the questions I often get from moms is, well, if I'm anemic, is that gonna mean that my baby's anemic? I've heard that breast milk doesn't have much iron in it. Is that my fault? And no, it's really not. Breast milk does not have much iron in it. It is, by the way, very bioavailable. So what little is there is pretty easily absorbed. However, it's really not enough to support all of the iron needs for the baby once they're about four to six months old, up to their first birthday. And so that's where complimentary foods come in. But in the very beginning, even if you're anemic, your breast milk actually still has about the same amount of iron in it as a mama who is not anemic. Again, our bodies intrinsically protect the baby and support the baby. You're the one that needs replacement, and that supplementation really is for you. Just for reference, most women are probably going to be needing about 18 to 27 milligrams a day. And that can actually be achieved through the supplement and your hostnatal vitamin. Just make sure you're looking at the amount because sometimes there's only a small amount in those. Um, since it is a stored micronutrient, that's not always safe to have high high amounts in. And then the other places that I typically recommend getting it are things like beans and lentils. You can get it from, of course, red meat and fortified cereals, but grains are another really good one. Like whole grains can be that. Fortified grains can also do that too. And so this is really where prioritizing those iron-rich foods are really gonna be helpful. I think, especially in the first month postpartum. That's really when I tend to encourage that. Personally, if I make something for mama postpartum, I'm often taking over something like a beef stew if they eat meat, or if they if they don't, then I'm gonna do um tofu, something that's gonna have tofu or some soy protein in there paired with some vegetables to give them a good amount of amino acids. Okay, the next micronutrient I want to mention is actually iodine. And this is more about globally, like if you're using salt that's not iodized. Here in America, where we use iodized salt, this is gonna be pretty much achieved. So just making sure that you're not using only sea salt, for example, or you know, that if you have a prenatal vitamin, it has some in there. You actually absolutely need iodine for thyroid function for your baby. And this one is going to be influenced by intake. So this is one where you actually do have a little control over this. If it's not in your diet at all, then that could be worrisome for your baby. Your baby does need that. So just check your prenatal, think about that. 150 micrograms is typically what we're looking for in a daily amount. The other sources for that are gonna be in seafood that comes naturally in seafood, as well as eggs and dairy. And then one other one that we talk about in the newborn visits, often I talk about is vitamin D. So vitamin D is really important for your bone health, your immune function. And often low levels are gonna be present for most Americans. In fact, generally speaking, you know, I tend to just recommend general like supplementation if you are living in a latitude where you aren't getting a lot of it. And currently, because we also know that breast milk does not offer much vitamin D, your diet can have, if your diet has adequate sources, it can actually translate to adequate sources in the breast milk itself. Um, but you have to get upwards of like 6,500 IU a day in order to achieve enough levels high enough in the breast milk that will support the baby. For reference, most prenatal vitamins are only going to have about 600 to 1,000 IU. So definitely not enough if that's your only source. And in terms of sources from food, it's hard to get enough. You'd have to drink a lot of milk, like insane amounts of milk to get 6,000 IU a day. It's like 200 IU per cup of milk. I mean, it's really not that much. Um, fatty fish is also going to be a source, but is often not the most commonly consumed source. So, generally speaking, this is one where you actually do want to think about some supplementation. And you will rarely hear me say that. And I already mentioned omega-3 fatty acids, just making sure that those are in your supplements as well or that they're in your diet. And then choline is the last one. And this is important because this one actually is influenced by your maternal intake as well. So if it's not in your diet, there's opportunity to augment this with your supplement or from food. We're looking for somewhere around 500 micrograms a day. And the best sources for this are in eggs, meat, and fish, and some soy products as well. So, you know, in total, like when we think about the macronutrients, your body's doing that kind of no matter what. But you need to get enough food to support your own body in that production. When it comes to the micronutrients, you actually do have some influence in your diet over these micronutrients coming out, specifically in the form of vitamin D, iodine, choline, DHA. And I didn't go into detail, but zinc as well. And my hope here is to encourage you that there's no one single product out there that you need, need, need in order to be able to produce the best milk. Take care of yourself. Let other people help take care of you. And don't forget your prenatal, your postnatal, and then everything's gonna be fine. You're gonna be awesome and your milk is gonna be awesome. Your baby's gonna grow beautifully. And I hope that this leaves you with a little bit of encouragement that at the end of the day, it's really about making sure that you are in a good place where you're taken care of because your body does all the heavy lifting. You just gotta give it in. And so if you're listening to this and you're thinking, okay, that is all super cool, but like I am now really curious about what's in the breast milk in greater detail. Or maybe you're feeling like, well, what's in the formula? How does that compare? Actually, I have a masterclass I'm gonna be hosting on January 25th. In the show notes, I'll have a link to sign up and register if you're interested. My hope is that this leaves you with some encouragement. And if you're listening to this and it's well past January, no big deal. Welcome. Hope you're enjoying it. Stick around for some more. Thanks so much for listening.