Breastfeeding, Dairy Products, and Infant Milk Allergies

What to Do If Your Baby Is Sensitive to the Protein in Cow's Milk

Pretty young mom carrying a breastfeeding baby with baby carrier in the street
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Many breastfeeding moms worry that drinking milk or eating cheese, ice cream, or yogurt will cause sensitivities and allergic reactions in their babies. It's true that much of the food that you eat does travel into your breast milk. While most babies will never react to any of the foods in their mother's diet, some will. And when a child does have a reaction to something in breast milk, the culprit is often cow's milk.

Symptoms of a Cow's Milk Allergy or Sensitivity

The most common symptoms of a cow's milk sensitivity in a breastfed baby are stomach-related. The proteins in cow's milk can cause gas in a baby's stomach and intestines, which can lead to pain, vomiting, or diarrhea. A food allergy could also cause reflux, symptoms of colic, a rash or hives, and bloody poop. It could make your baby very irritable or fussy. 

If your child is in pain or has any of these symptoms, call the doctor. Since many of these symptoms are also caused by other conditions, try to be as detailed as possible when you're describing what's going on with your baby. The more information the doctor has (such as whether there is a family history of food allergies), the easier it will be to narrow down the cause. Then, together, you can create a plan to make things better.

Is a Cow's Milk Allergy the Same as Lactose Intolerance?

A baby with an allergy to cow's milk is reacting to the protein in cow's milk. Lactose is a sugar, not a protein. It's very unusual for a newborn or young child to be sensitive to lactose. Lactose intolerance is typically seen in adults or older children. And if your baby does have a milk allergy, lactose-free dairy products will still cause a reaction.

Breastfeeding When Your Child Is Sensitive to Cow's Milk

You don't have to stop breastfeeding because of a suspected sensitivity to cow's milk protein. If your baby's symptoms aren't too bad, you can eliminate cow's milk from your diet, along with common dairy foods like cheese, yogurt, and butter. But if your baby's symptoms are more severe, your doctor may recommend that you don't consume anything that has cow's milk in it. Once you get started, you may see things begin to improve in as little as a few days. But it can take two to three weeks to really see results, so be patient and keep your mind on the goal.  

If, after two weeks of a dairy-free diet, you do not see any difference and your child is still showing signs of an allergy, then dairy is probably not the cause of your baby's issues; another allergen, or another medical condition, may be the problem. But if you do see improvement, then do your best to stay on the dairy-free diet. 

Reintroducing Dairy Products

You don't necessarily have to stay away from dairy for as long as you decide to breastfeed. If your baby has a sensitivity to cow's milk, once you've eliminated all the dairy and your child is feeling better, you can wait a few weeks or months, then slowly reintroduce some dairy products back into your diet. If your baby starts to react, you can stop the dairy once again. Keep trying every few weeks or so, and as your baby gets older, he may be able to tolerate it more and more. 

Food allergies are less common, but they can be more serious. So, if your child has had a severe reaction to the cow's milk protein, you have to be much more careful. Discuss the reintroduction of cow's milk into your diet with your child's doctor. You may have to remain dairy-free until you wean your child, or you may be able to reintroduce dairy under the doctor's direct supervision. 

Dairy-Free Diet Options

There are many substitutes for cow's milk and milk products available. Just look for dairy-free on the labels at the grocery store (since milk is a known allergen, it must be identified on food labels). Do remember that milk can be found in many different products, including soups, salad dressing, and baked goods, so you have to stay vigilant in the supermarket.

You may be surprised to find that you like some dairy-free options better. You may even feel better yourself once you eliminate dairy. But keep in mind that even though a reaction to cow's milk is the more common one, soy and nuts can also cause allergies in breastfed babies. And you'll need to be careful that you consume enough calcium from non-dairy sources.

Milk Allergies and Infant Formula

If your baby breastfeeds and takes formula, a cow's milk-based formula can cause the same milk allergy symptoms. It may even be worse. You should talk to your child's health care provider about changing your baby's formula. Soy formula is an option, but it can also cause allergies in some infants who are allergic to the cow's milk protein. A hypoallergenic formula may be the way to go.

A Word From Verywell

The longer you can continue to breastfeed your baby, the better. However, it can be exhausting and difficult to care for a child who cries frequently and appears to be in pain, especially if you don't have much support. Elimination diets are often quite challenging too. Talk to your partner, your doctor, and your baby's doctor to get all the information you need to make the best choice you can for you, your child, and your family. Sometimes that means weaning your baby. After a period of healing, if you decide to try breastfeeding again, you certainly can. 

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Article Sources

  1. University of Michigan Health System, "Cow's Milk Sensitivity in Babies"

  2. Greer FR, Sicherer SH, Burks AW. Effects of early nutritional interventions on the development of atopic disease in infants and children: the role of maternal dietary restriction, breastfeeding, timing of introduction of complementary foods, and hydrolyzed formulas. Pediatrics. 2008. Jan 1;121(1):183-91.

  3. Hill DJ, Roy N, Heine RG, Hosking CS, Francis DE, Brown J, Speirs B, Sadowsky J, Carlin JB. Effect of a low-allergen maternal diet on colic among breastfed infants: a randomized, controlled trial. Pediatrics. 2005 Nov 1;116(5):e709-15. DOI:

    10.1542/peds.2005-0147

Additional Reading

  • Protocol AB. ABM clinical protocol# 24: allergic proctocolitis in the exclusively breastfed infant. Breastfeeding Medicine. 2011;6(6).

  • Riordan J, Wambach K. Breastfeeding and Human Lactation Fourth Edition. Jones and Bartlett Learning. 2014.