Breastfeeding: How What You Eat Impacts You And Your Baby

By Cassandra Forsythe, PhD, RD

breastfeeding7-450x338Over the past nine months, you have been preparing your body and mind for this moment, and the day has finally arrived! As you welcome your new baby into the world, the real work begins.

In addition to healing your body after this life-changing event, you have the new full-time job of protecting and feeding this tiny human being.

When it comes to feeding your little one, there is a vast ocean of information available about what, when, and how to feed your baby as well as what, when, and how you should eat—particularly if you’re breastfeeding.

While this article is about nutrition considerations for breastfeeding, it is not our assumption that all mothers can and want to breastfeed. We understand that this is a very personal matter and we encourage you to take the course of action that you feel is best for you and your baby, based on your individual circumstances.

The Benefits of Breastfeeding

Research (and the experiences hundreds of generations of women) have shown that breastfeeding offers numerous benefits to both mother and child. The American Academy of Pediatrics, the Institute of Medicine, and the World Health Organization have documented an expansive body of research and data on these benefits1a-d.

Breast milk is considered nutritionally complete, delivering precisely the nutrients your baby needs. These nutrients can help reduce your child’s likelihood of obesity and diabetes later on (of course, all of those outcomes will also be influenced by your child’s nutrition and activity level as he or she grows and develops)1a-d.

In addition to providing the ideal combination of nutrients your newborn baby needs to thrive, breastfeeding benefits you, both psychologically and physiologically 1a-d. For example, breastfeeding can help guard against postpartum depression1a, 2, helps forms a strong bond between you and your baby, and reduces your long-term risk of Type 2 diabetes, rheumatoid arthritis and breast cancer1a-d. Breastfeeding also helps your uterus return to its normal size via the release of the hormone oxytocin, which causes the uterus to contract more vigorously (which is why you may experience discomfort in your uterus when you first begin breastfeeding)1a.

When Breastfeeding Is Not Possible Or May Not Your Best Option

Sometimes a new mother has full intention of breastfeeding, but it may not be possible or realistic for a variety of reasons. For example, the baby may have trouble latching, which reduces milk production and makes it difficult to provide enough milk for the baby. Or, breastfeeding may be incredibly uncomfortable or painful for the mother, which makes it unsustainable long term.

Additionally, while you may often hear about the bonding benefits of breastfeeding, something that isn’t discussed as often or as openly is how emotionally taxing breastfeeding can be on a new mother. The frequent feedings can become very stressful, and the mother could become frustrated and start feeling detached from the experience, from her body, and from her baby. This usually occurs in the first couple months until you feel more comfortable with breastfeeding and the use of your breasts as a feeding implement. Family, friends and your OB/GYN are all helpful at this time to help you deal with the initial discomfort and emotional toll.

breastfeeding6-350x375It may also be helpful to meet with a lactation consultant to work through some of the issues that may arise if you’re having trouble breastfeeding and want to keep trying. A lactation consultant is specially trained to help you have the best outcomes and experiences with breastfeeding if you so chose to pursue it. She may suggest pumping exclusively if you are struggling with latching, discomfort for you, and time management. Some initial issues (like low milk production, for example) can often be resolved when the mother makes a few nutritional changes, coupled with the support of a lactation consultant and/or her OB/GYN, who can make sure you and your baby’s technique is ideal.

With respect to your nutrition, if you are currently struggling to breastfeed your baby, you may find some helpful information in this article.

Note: As we said, breastfeeding certainly isn’t the only way to provide your baby with the necessary nutrients to grow strong and healthy. If you have decided not to breastfeed, or are unable to breastfeed, there are many excellent infant formulas available, specially created to meet your baby’s nutritional needs. We recommend that you seek guidance from your OB/GYN doctor, lactation consultant or a registered dietitian who specializes in infant nutrition.

This article highlights several key considerations aimed at optimizing your nutrition to ensure that you’re getting the nutrients necessary to heal and fuel your body and produce ample, high-quality breast milk to nourish your baby.


Consuming adequate calories is the most important factor in maintaining a steady supply of breast milk. Exactly how many calories a breastfeeding woman needs depends on her body fat and lean mass levels and how active she is. The standard recommendation for a woman who is breastfeeding (not taking into account the aforementioned factors) is to consume an additional 450-500 calories above non-pregnant energy needs daily1a. This could be too much for some women, and insufficient for others.

Some organizations suggest that you will not need these extra calories in the first six months of breastfeeding, because your body will use your maternal fat stores to give you the extra energy you need. Others suggest those extra calories are needed right away, given that you are expending a lot of calories both, to repair your body after birth, and to make breast milk3. The truth is, your body is very dynamic during this time, and every woman’s body is different. It’s impossible to give an exact recommendation for many calories you should be consuming. You may realize these extra calories are too much if you are gaining body weight or excessive body fat. Likewise, if your are losing weight rapidly, you’re not producing enough breast milk, or you’re feeling excessively lethargic, it is likely that you’re not consuming enough calories.

breastfeeding3-350x375Right after giving birth, and for a while afterwards, your body will not look, function, or feel the same as it did before you became pregnant. While you may feel tempted to eat fewer calories in an effort to speed up post-baby weight loss or “get your pre-baby body back,” we encourage you to take your time and enjoy bonding with your baby—especially during these first six to nine months. In addition to nourishing your baby, our body is trying to recover and heal after growing and changing dramatically for the past nine months.

I personally breastfed for 11 and a half months (I tried to make it to a full year, but just couldn’t due to work demands). My body finally felt normal a few months after I stopped breastfeeding. This was my own experience, and yours may be different.

As noted above, with respect to needing fewer calories, if you gained more than the usual 25-30 pounds during your pregnancy, some of your calorie requirements might be supplied by stored body fat during the first six months of breastfeeding. Thus, calories will not need to be provided entirely by your daily food intake.

Similarly, if you were very active during pregnancy and did not gain a lot of weight or fat, or are very active post-pregnancy now (especially if you have another toddler at home to keep up with), you may need to maintain a higher calorie intake to ensure you’re producing enough breast milk. You also may need to consume higher calories if you are breastfeeding more than one child, if you are in your teens, or if you become pregnant again while you are still breastfeeding.

The quality of the calories you consume is just as important as the quantity. It’s OK if your nutrition was a little less-than-optimal for a while during your pregnancy. In fact, it’s totally normal, given the wild hormonal changes your body has experienced over the past nine months. If you were practicing healthy nutrition habits before you became pregnant (before all the weird food cravings and aversions!), it’s time to dust them off and start practicing them to some degree again. Give yourself some grace, particularly during this period.

You are still dealing with a plethora of hormones that weren’t there pre-pregnancy, so don’t get frustrated if you can’t always take charge of a “perfect day” of eating.

Most importantly, eating a variety of healthy proteins, complex carbohydrates (vegetables, grains, and legumes), fruits, and fats (nuts and oils), is all you really need to focus on. If you have strange cravings for other foods you don’t normally eat, that’s OK too. Your body is pretty smart and can help you understand what you need. And if you’re starting to make improvements to your nutrition for the first time too, that’s great!

What should you eat if you are breastfeeding?

A healthy diet for a breastfeeding woman includes the following:


As you may already be aware, protein is a building block for your muscle tissues, it is also one of the building blocks of breast milk. Although it is present in small quantities in breast milk (0.9 grams of protein per 100 mL fluid, which is less than unprocessed cow’s milk) it is one of the key nutrients in breast milk, which your baby needs in order to develop all the various proteins within their own body (muscle, enzymes, contractile proteins and even hormones, oh my!)3. Your body is smart and does a very good job ensuring that your breast milk contains enough protein.

However, to prevent your own body from breaking down its own muscle tissue protein to provide it for your baby, you need to make sure you’re consuming at least 1.0-1.2 grams of protein per 1 kilogram of body weight, or at least 71 grams of protein per day3. You can get this easily with a daily variety of pastured/grass-fed beef, chicken, eggs, or wild caught, low-mercury fish such as salmon (see NRDC Mercury Guide for more information), organic dairy, and legumes. Common servings sizes in each meal for protein include one or two whole eggs, a palm-size amount of meat, poultry, or fish, and a one-third cup portion of beans or legumes (like hummus). Protein powders (such as whey, pea, or rice) that contain minimal or no artificial ingredients or sweeteners can help you supplement your daily protein intake, if you’re having issues eating whole food proteins in your meals due to time or taste aversions.

breastfeeding5-350x375Fat (Especially Omega-3 and Omega-6)

Both, during pregnancy and when you’re breastfeeding, it’s crucial to consume a variety of fat and essential fat sources. This is what your baby’s brain is made up of and what it needs to develop properly. There is a rapid accumulation of arachidonic acid (AA, an essential omega-6 fatty acid) and docosahexaenoic acid (DHA, an essential omega-3 fatty acid) in a newborn’s brain, as well as DHA in the retinas, and AA in their entire body4. In a moment, we’ll take a closer look at these essential fats and their importance.

Try to include a serving of healthy fats in each meal and snack you eat. One serving can be: one whole egg yolk, a palm-size serving of salmon, a small handful of nuts or seeds, or one to two tablespoons of natural nut butter. The total amount you should consume per day will vary depending on your unique caloric requirements and should be no less than 20 percent of your total calorie intake3.

Vegetables and Fruits

Vegetables and fruits should always make up a large portion of your daily food intake because they are an excellent source of the dietary fiber, which is necessary for proper elimination and prevention of cardiovascular disease. These foods also provide vitamins, minerals, and antioxidants, which help prevent disease and promote ideal health. Just like with fats, at each meal include vegetables (non-starchy such as leafy greens and colorful, watery veggies, and starchy like squash, parsnips, or carrots), and fruits and berries that you enjoy. The serving size of vegetable you should consume depends on its nutrient and caloric density; non-starchy, leafy greens and colorful veggies are low in calories and can be eaten in large quantities (two to three cups in a meal). Starchy veggies like squash, and fruits like bananas, are higher in carbohydrates and calories and should usually be served in smaller quantities.


Combined with protein and fat (for example, oatmeal with whey protein and peanut butter) carbohydrates help keep your blood sugar stable, and if you’ve resumed working out, they restore the glycogen you used during exercise. Choose whole-food carbohydrate sources such as sweet potatoes, white and red potato varieties (one large or medium potato per meal), whole grains such as oats (one-third cup dry), rice or quinoa (one-half cup cooked), or sprouted grains (two slices of Ezekiel bread). Include a serving in your meals any time, but especially with your pre- and post-workout meals.

When and how much should you eat?

There is no “best” way to structure your meals, so long as you’re focusing on the recommendations mentioned above. It's all about listening to your hunger cues. Some breastfeeding women end up grazing all day because they always feel hungry. If grazing or eating multiple smaller meals throughout the day works for you, great. If you would like to minimize grazing, try having slightly bigger meals with a little more protein or fat, to help you feel fuller and help you go a little longer between meals. Eat when you’re hungry, stop when you’re satisfied, and eat as often as you feel you need to.

Key Nutrients for Breastfeeding Women

In addition to calories, several nutrients are particularly important when breastfeeding.


Many breastfeeding women worry about their calcium status given that they are producing milk. Naturally, calcium is an important ingredient in a balanced diet, but your requirements during breastfeeding are no different than when you are not breastfeeding. The amount you need now is the same you needed before you started producing milk, which is 1000mg per day. If you ate dairy before you were pregnant, you can continue to do so while breastfeeding, unless your baby has a particular issue with dairy foods in your breastmilk as mentioned above. You can obtain ample calcium from other foods, such as kale, collard and turnip greens, cabbage, bok choy, canned fish such as sardines or salmon (with bones), fortified soy or almond milk, and soybeans, and tofu products made with calcium sulfate6.

Omega-3 and Omega-6 fatty acids

Breast milk delivers a rich supply of essential omega-3 and omega-6 fatty acids that your baby needs for proper brain, nervous system and eyesight development. As mentioned earlier, DHA and AA (also known as ARA) are two of the essential fatty acids your baby needs the most, and are supplied in high quantities in breast milk. Babies don’t produce these fatty acids easily on their own, and will suffer without them. Look at the label for any baby formula, and you’ll notice DHA and ARA are often singled out and promoted on the front of the packaging and included in the ingredients list.

During breastfeeding, especially the early months, you may feel a craving for fatty fish like salmon, and high-fat foods like nut butters and egg yolks. Your body is giving up a lot of its own essential fatty acids and stored fat toward the production of breast milk for your baby. Choose foods rich in omega-3 (such as salmon, fish or krill oil, flax seeds and oil) and omega-6 fatty acids (such as nuts and nut butters, and hemp seeds and hemp butter). Add flax seed oil to your salads or cooked vegetables, snack on some some walnuts, pumpkin seeds and hemp seeds, and eat salmon or tuna at least once or twice a week. Even if you don’t crave these foods, you will benefit from including more of them in your diet.

Pastured/grass-fed beef and certain products fortified with omega-3 or DHA (eggs, dairy, orange juice, for example), are not only excellent sources of protein, but they can also help you get a bit more of those essential fatty acids. You can also add a supplement rich in DHA, such as krill oil or algae DHA oil. Increasing DHA in your diet will increase DHA in breastmilk; 200 mg per day is recommended during pregnancy and while breastfeeding. As long as you consume foods rich in linoleic acid (an omega-6), you will get enough ARA. Most foods that contain fat contain some linoleic acids, particularly nuts, seeds, and animal fats. As you may have gathered by now, following a very low-fat diet while breastfeeding is not recommended.

Vitamin D

Vitamin D is important for the health and development of a growing infant, to support bone health and prevent rickets. However, breast milk is typically low in vitamin D. Very few foods are high enough in vitamin D, making it very difficult to obtain this nutrient strictly through your diet. Supplementation is the best way to increase the vitamin D content of your breast milk.

A study of breastfeeding mothers recently published in the American Journal of Clinical Nutrition7 showed that there was a significant difference in vitamin D breast milk content when a mother supplemented with 2000 IU per day of vitamin D3, compared to 1000 IU per day, or no vitamin D at all. These mothers took two doses of 1000 IU of vitamin D3 per day, starting at 27 weeks gestation, although starting supplementation earlier may be beneficial to build up adequate stores upon delivery, or in the case of premature birth.

The American Academy of Pediatrics also recommends that direct supplementation of 400 IU VItamin D3 to your infant is ideal, or you can consume 6500 IU/day assuming you are not deficient yourself. Your pediatrician will also suggest this to you, and you can find many over-the-counter vitamin D3 drops at your local pharmacy.


The final and most important aspect of lactation is your fluid intake. Breast milk is primarily made up of water, therefore your hydration status is very important.

In a recent study completed by some of my colleagues at the University of Connecticut8, it was shown that a mother’s body will defend the volume of fluid in breast milk over and beyond the total amount of fluid she takes in each day. Plainly stated, if your fluid intake is inadequate, your baby takes priority, and you will be the one feeling the negative effects of dehydration. You will produce less urine and have a higher urine osmolality (the concentration of bodily substances, such as sodium, potassium, glucose and urea, in your pee). This could lead to bladder or kidney infections, or symptoms of dehydration such as dizziness, moodiness or confusion.

Should breastfeeding women avoid athletic supplements?

A common question among active breastfeeding moms is whether they can continue some of their previous sports nutrition products while breastfeeding. Supplements such as creatine and branched chain amino acids (BCAAs).

To my knowledge there is no evidence in the scientific literature indicating that those supplements are harmful or unsafe for your child, so my answer is that the choice is always yours. Some experts suggest that creatine or BCAAs are safe, while others say it can be potentially hazardous, but again, as far as I know, there is no literature to support any claims of potential hazards. Your best bet during this time is to consume a nutritionally adequate diet as described above, with plenty of high-quality proteins, vegetables and fruits, and fluids. This tactic should give your body what it needs to help with exercise recovery, and once you are done breastfeeding, you can resume taking your sports supplements.

Can the foods you eat affect your baby's digestion and well-being?

Some foods you eat could cause your baby to have excessive gas or other digestive issues, or could create an aversion to breast milk. Many people believe that spicy, garlicky, or acidic foods can be troublesome for a baby’s digestion, but the current available research doesn’t support that notion. In fact, most foods (including spicy and exotic ones) eaten by the mother are well tolerated by breastfeeding infants5. You may need to experiment if you notice changes in the way your baby is feeding after you’ve eaten some of these foods.

Dairy, Caffeine, and Alcohol

If you’ve eaten dairy products and your baby is sensitive to milk proteins passed on via your breast milk, (which is quite common in lactation) you will need to avoid whey protein and foods that contain dairy, and opt for non-dairy protein options instead. Signs that your baby may be sensitive to dairy proteins can include: colic-like symptoms, eczema, wheezing, vomiting, diarrhea, constipation, hives, and/or a stuffy, itchy nose. Always consult with your pediatrician.

While breastfeeding you should also try to limit your intake of caffeine. Caffeine in breast milk may lead to prolonged waking periods or agitation in your baby. One or two cups of coffee per day in the morning is usually normal and OK5.

Alcohol should be limited to an occasional single drink, because it is transferred to breast milk. The Institute of Medicine reports that eight ounces of wine, 12 ounces of beer, or two ounces of hard liquor are safe if breastfeeding is then delayed for two hours5.

Breastfeeding and Weight Loss / Fat Loss

It’s not uncommon to hear new mothers talk about breastfeeding as a weight loss “bonus” because they believe the increased calorie burn will help with weight loss. With the ever-present pressure to not only be a perfect mother right from the start, but to also “get your pre-baby body back” it’s no wonder many new mothers share this sentiment. While fat loss—or simply getting to a point where you feel more comfortable with your body post-pregnancy—is a wholly valid goal, we urge you to practice grace and compassion toward yourself, your body, and your new role. You just created and gave birth to a human, after all! Take your time during this period to focus on bonding, adjusting to a new schedule, and nourishing your baby.


Whether or not you are breastfeeding—and regardless of how long you can or will breastfeed—your nutritional choices can make a difference for your body and your baby during the early postpartum phase. If you’re breastfeeding, the foods you eat can impact the quality and quantity of the breast milk you produce for your baby. If you are not breastfeeding, your body still needs good nutrition now more than to recover and heal from labor and delivery, and to help you maintain the energy that caring for a newborn requires.

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About the author:  Cassandra Forsythe, PhD, RD

Cassandra Forsythe, PhD, RD, CSCS, CISSN is an Assistant Professor at Central Connecticut State University (CCSU). She is a mother, entrepreneur, health and fitness enthusiast, and the author of The Modern Woman’s Guide To Good Nutrition. Cass is also on the advisory boards for Women’s Health magazine, and You can learn more about Cass on her website.


  1. Breastfeeding Benefits: a. American Academy of Pediatrics Policy on Breastfeeding and Use of Human Milk b. World Health Organization, 10 Facts About Breastfeeding c. The Endowment for Human Development, How Breastfeeding Benefits Mothers and Babies d. Shamir R. The benefits of breastfeeding. Nestle Nutr Inst Workshop Ser. 2016;86:67-76
  2. Henderson JJ, Evans SF, Straton JA, Priest SR, Hagan R. Impact of postnatal depression on breastfeeding duration. Birth. 2003;30(3):175–180pmid:12911800
  3. American Academy of Pediatrics, Dietary Reference Intake: Macronutrients
  4. Clandinin MT, Flieth M. Dietary PUFA for preterm and term infants: review of clinical studies. Crit Rev Food Sci Nutr. 2005;45(3):205-29.
  5. American Academy of Pediatrics, Bright Futures: Nutrition Issues & Concerns
  6. USDA MyPlate, Non-Dairy Sources of Calcium
  7. Wall CR et al. Vitamin D activity of breast milk in women randomly assigned to vitamin D3 supplementation during pregnancy. Am J Clin Nutr. 2016 Feb 103(2); 382-8
  8. McKenzie A et al. Relationships Between Fluid Intake, Breast Milk Volume, and Urine Volume in Lactating Women. FASEB J April 2015 29:133.3

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