The breastfeeding diet: Your guide to nutrition while nursing

Women's Health
Baby Feeding from the Breast of Her Mother

Having a baby puts many of your daily choices at the forefront of your mind. Decisions like what you eat and how much sleep you get will affect your health and the health of your developing baby.

If you decide to breastfeed, many of these questions linger after delivery — especially about nutrition. You might wonder if there are nutrients you need to increase or if there are foods you need to avoid. On top of that, you’ll need to consider your own body’s needs, especially while it is still healing after giving birth.

An overview of breastfeeding: How does what I eat affect my breast milk?

Nutrition while breastfeeding is different from during pregnancy. When you’re pregnant, everything you eat and drink can travel directly to your baby. This puts many women on high alert about what goes in their bodies — and rightfully so.

“Compared to pregnancy, breastfeeding isn’t as direct a connection with your baby. Breast milk is made in the mammary glands, not directly from your diet. Instead, your body uses what nutrients are available to make breast milk,” says Donna Sinnott, a lactation consultant at Main Line Health.

Because of this, if you happen to be low in certain nutrients, your body will always prioritize your breast milk. While this doesn’t mean you should ignore healthy eating guidelines, you can be confident that your baby is getting highly nutritious breast milk, even if you happen to be a little low on certain nutrients.

What’s more, during breastfeeding, your mammary glands are in control of what makes it to your baby and what doesn’t. As a result, a moderate amount of caffeine and the occasional glass of wine won’t affect your baby in the same way as when you were pregnant.

Still, breastfeeding means you’re a primary source of nutrition for your baby, so what you eat and drink can have an impact on their well-being.

Nutrition while breastfeeding: What should I eat and drink while nursing?

When you’re breastfeeding, your diet is sustaining not just your body’s daily needs — but also the needs of your growing baby. Because of this, breastfeeding mothers usually need to consume more calories compared to before pregnancy.

While many factors will determine how much you need to eat while breastfeeding (including your age, activity level and body mass index), you should aim for roughly 330 to 400 additional calories.

A good rule is to eat foods with all the colors of the rainbow to ensure you and your baby get enough nutrients. Focus on a variety of foods, including fruits, vegetables, dairy, grains and protein foods. You may also need to increase certain nutrients, such as:

  • Iodine (found in eggs, seafood, dairy products and iodized table salt)
  • Choline (found in eggs, dairy products, meat, beans, peas and lentils)
  • Folate (found in dark green vegetables, peas, lentils and beans)

If you’re taking a prenatal vitamin, you can continue to take your prenatal vitamins or get a woman’s multivitamin. But for others, such as those who follow a vegetarian or vegan diet, a multivitamin with B 12 added will help avoid nutritional deficiencies.

Staying hydrated while breastfeeding

Your body requires water to make breast milk. While breastfeeding, it’s important to stay hydrated. For most women, this is about 8 to 16 cups of water or fluid in a day. This can be from water, other beverages and even food, like soup.

One way to drink more water is to drink a glass of water every time you nurse your baby. Some women find it helpful to have a nursing area equipped with water, snacks and other things you’ll want nearby when you breastfeed.

“Most importantly, listen to your body. If you’re thirsty, don’t ignore this critical signal to hydrate,” says Donna.

Are there any foods I should avoid or limit while breastfeeding?

Unlike pregnancy, you generally don’t need to keep certain foods out of your diet while breastfeeding. This is because of how your mammary glands control what makes it into your breast milk. However, there are a few foods and beverages you’ll want to keep an eye on.


Certain kinds of seafood contain high amounts of mercury, which can pass from your breast milk to your baby. This can impact your baby’s nervous system and brain development. A good rule is to consume two to three ounces, two to three times a week and you can have sushi again too.

Most fish contain safe levels of mercury. But some types (including marlin, king mackerel, swordfish, shark and orange roughy) have unsafe amounts, and they are best to avoid completely.

Keep in mind — fish is still a great source of protein and nutrients. To read more about which varieties of fish to prioritize and which to steer clear of, read the Food and Drug Administration’s advice about eating fish.


When breastfeeding, small amounts of caffeine can make it to your baby. Normally, this isn’t a concern, especially if you stick to moderate amounts.

In general, you should limit your caffeine intake to roughly 300 milligrams or less per day — or the equivalent of 2 to 3 cups of coffee or less. Caffeine sensitivity is genetic, so while some mothers can have large amount, most can’t. Some breastfeeding mothers who drink very high amounts of caffeine — upwards of 10 cups of coffee each day — have reported poor sleeping, jitteriness and irritability in their babies.


Avoiding alcohol is the safest approach while breastfeeding. However, small amounts of alcohol (up to 1 standard drink per day) are not known to be dangerous for the baby. If you do choose to drink alcohol while breastfeeding, it’s safest to wait two hours after one drink before nursing or pumping.

What if my baby reacts to certain foods in my diet?

Breast milk, which contains the food and drink in the breastfeeding mom’s diet, is not usually the cause of allergic reactions in babies. In fact, only about 3% of babies who are exclusively breastfed (meaning they only received breast milk) have an allergy to something in it.

Still, keep an eye out for signs of an allergy, including:

  • Vomiting
  • Rash or hives
  • Trouble breathing, wheezing or shortness of breath
  • Swelling of the face or throat

A food intolerance, which is a digestive issue rather than an immune system reaction, means your baby has a hard time breaking down the enzymes from a specific food. The most common food intolerances in babies are cow’s milk and soy milk. So if you’re concerned about a food allergy or intolerance in your baby, talk to your baby’s pediatrician or a lactation specialist. In some cases, they may suggest changes to your diet while you’re breastfeeding.

Maintaining a healthy diet throughout your breastfeeding journey

Breast milk is often referred to as “liquid gold” or a “superfood.” It provides the perfect amount of nutrients for your baby as they grow and develop. To support your body as it manages this remarkable process, make sure you’re eating enough of the right nutrients as long as you breastfeed.

The benefits of breastfeeding or providing your breast milk for your baby can last a lifetime. By honoring your body’s needs and eating healthy, you’ll be taking care of both you and your baby.

Next steps:

Make an appointment with an OB/GYN provider
Learn more about obstetrics at Main Line Health
6 changes during pregnancy that may surprise you