Elimination Diet

Most breastfeeding mothers can eat pretty much whatever they like 1. But some exclusively breastfed babies can have allergies or intolerances to traces of food proteins that enter breast milk from mother’s diet. The most common food to trigger a reaction in susceptible babies through mother’s milk is cows’ milk—see Milk Allergy in Babies—but other allergens (substances that cause an allergic reaction) could be a trigger for your baby too. Other common allergens include egg, soya, fish/seafood, peanut or tree nuts, wheat or other grains, and certain fruits. The first line of treatment for a food allergy is for the mother to try to find the food or foods causing the reaction in her baby by way of an elimination diet.

What is an elimination diet?

An elimination or exclusion diet is one that removes the foods from one’s diet that are causing an allergic response. If the problem food is cows’ milk, it can be difficult to eliminate completely because cows’ milk products are not only found in dairy produce but also as “hidden dairy” in unexpected food items. In other words cows’ milk proteins can be listed in the ingredients of something you wouldn’t expect, or disguised by unusual names. Elimination diets can be difficult to follow and are often recommended to be under the supervision of a dietitian to ensure a heathy diet for the mother2 3 4.

Multiple allergens?

If a baby is sensitive to one thing they may be sensitive to other common allergens too so it can be trial and error to know which foods to avoid. Because of this, it is not advisable to substitute anything potentially allergenic during an elimination trial. For example unless you know for sure that your baby doesn’t react to soy, avoid substituting soy products for dairy during an elimination trial, because soya is also highly allergenic.

How do I start an elimination diet?

Some mothers try eliminating one allergen at a time to see if there is any improvement while others choose to follow a low allergen diet or total elimination diet from the beginning.

Eliminating one food at a time

The Academy of Breastfeeding Medicine (ABM) protocol for allergic proctocolitis describes the different ways to go about elimination diets. The simplest way is to try eliminating one food or a group of foods at a time:

To make it as simple as possible, one can start by eliminating the most likely suspects for allergies one at a time (i.e., cow’s milk [and products made with cow’s milk like cheese, butter, ice cream, other dairy products, beef products also affect some babies], soy, citrus fruits, eggs, nuts, peanuts, wheat, corn, strawberries, and chocolate). Mothers are instructed to eliminate one food or food group (e.g., dairy products) at a time and wait a minimum of 2 weeks and up to 4 weeks. Most cases will improve within 72–96 hours.

The protocol goes on to describe how a mother can reintroduce a food if the baby’s symptoms remain the same and move on to another food to eliminate. They point out:

when eliminating cow’s milk, eliminate anything made with cow’s milk, not forgetting the specific protein components like casein, whey, lactoglobulin, etc.; it is important to read labels for these other component ingredients

Avoiding allergens

It can be very difficult to spot labelling of food allergens used as ingredients in foods if they are listed under unusual names. In addition, not all trace amounts will be labelled, yet even trace amounts can sometimes cause a reaction in the human body. Some medications, sweets, cosmetics and even asthma sprays and vaccines may have allergenic ingredients too 5. Some mothers trying to follow a soy free diet have noticed that Pregnacare causes a reaction (Vitamin E is listed as derived from soya). Resources that help steer you through the various names for allergens include:

Calcium and dairy elimination diets

It is recommended that mothers on a dairy elimination diet take calcium supplements 67. The following information sheet has a useful tips box for maximising your absorption of calcium;

It is strongly recommended that people eliminating dairy take 1,000mg of calcium a day in supplements. 500mg of calcium twice a day works best. Always check with a doctor before starting any supplements.

A lactose free diet?

Having a reaction to traces of cows’ milk protein in the diet or via a mother’s diet via her breast milk is not the same as lactose intolerance although they could both be present at the same time. Lactose is added to breast milk in the breast regardless of maternal diet. For further reading see Lactose Intolerance in Babies.

The low allergen or total elimination diet

Another approach for an elimination diet is to eat a low allergen diet of only relatively “safe” or non-allergenic foods. Once your baby’s symptoms have settled you can reintroduce one food group at a time to identify the offender(s).

For babies with more significant symptoms, one can place the mother on a very low-allergen diet of foods like lamb, pears, squash, and rice. Again, this approach requires ongoing consultation with an experienced dietician.

Ask Dr Sears discusses a low allergen diet that involves cutting out all potentially allergenic food for two weeks followed by gradually reintroducing food and noticing if there is a reaction:

at this stage we recommend mainly protein elimination, namely dairy, beef, eggs, chicken, shellfish, soy, corn, wheat, and peanuts (plus any other foods you have learned bother baby)

Food diary

Other ideas in the ABM protocol include keeping a food diary to pinpoint the offending food, or eliminating likely allergens based on where the baby lives. For example, in some areas, hen’s eggs are a common cause of allergy, whereas in other localities peanuts are a common allergen. Diana Cassar-Uhl explains:

Unsure your diet is causing the trouble?  Keep a log of what you’re eating and another log of how your baby behaves.  Watch sleeping, fussy periods, diaper content and frequency, rashes, and anything else that raises a question for you.  It may be that something you ate on Monday affects your baby on Thursday – so keep that in mind as you look for correlations.

Elimination diet recipes

Allergy Friendly Recipes Cows’ Milk Protein Allergy Support

Meal Ideas for Dairy-Free/Soya-Free Eating from the Infant Procotcolitis website

How long will it take for an elimination diet to work?

Once a mother has excluded the trigger food from her diet, her baby’s symptoms may start to improve within three to four days (ABM, 2011) however it can take two to four weeks to see improvement8. This is likely to be associated with the time taken for any existing inflammatory reactions to settle down in the baby rather than the time taken for allergens to leave breast milk.

If your low allergen diet doesn’t seem to be working, consider avoiding other allergens like cigarette smoke, synthetic fragrances, bleach or detergents (including sterilising fluid residues in baby bottles), caffeine, artificial sweeteners (e.g. aspartame), artificial colours, preservatives or oral contraceptives (Minchin, 2015). There are more ideas in Milk Allergy in Babies.

Do I really need to go on an elimination diet?

Restricting a diet may not always be necessary if symptoms are mild. Discuss this with your health professional. Dr Jack Newman (Canadian paediatrician and breastfeeding expert) also points out in his book and on his Facebook page that there can be other causes for symptoms that may seem similar to allergy for example low milk supply. Contact your IBCLC lactation consultant so she can take a full history and rule out any other causes of fussy behaviour.


One day at a time

Although making changes to your diet is not easy this may only be for a short time and will almost always be better for your baby than any alternatives. Diana Cassar-Uhl says:

Remember that this change in your diet doesn’t have to be forever.  Many babies can tolerate small amounts of offending proteins that pass to them in breastmilk after the 6- or 9-month mark.  Take one day at a time, and know, without question, that if your baby is struggling with breastmilk, he will do far worse on regular baby milk preparations, which are made from the allergens you’re trying to avoid!  The available preparations for highly sensitive babies are very expensive and don’t offer the other protections from allergy and disease your milk provides.

Reintroducing cows’ milk or other allergens

GI Kids explain that children tend to grow out of cows’ milk protein allergy (or become more tolerant). They suggest that half of all babies with symptoms will have developed a tolerance by one year of age, and that mothers of most allergic breastfed infants will need to stay on an elimination diet for 6-12 months. After this point you can discuss with your health professional or dietitian about whether to try to reintroduce cows’ milk produce or other known allergens into yours and your breastfed babies diet and if so, how. There is a useful document by NHS Bath that describes a “Milk Ladder” approach see: Reintroduction of Milk into Your Child’s Diet.

Will an elimination diet in pregnancy help my next baby?

A paper by Fleischer et al 9 and the guidelines from the American Academy of Allergy, Asthma and Immunology (2013) do not advise avoidance/elimination diets during pregnancy or lactation as a means to prevent allergies.

Allergy author Maureen Minchin agrees with general advice not to exclude foods during pregnancy. However if there is a known problem in either parent e.g. if  mother knows she has cows’ milk allergy, Minchin says it may be worth avoiding cows’ milk, beef and blood products. Or, in the case of the allergic mother, at least reducing these allergens in her diet until she is symptom free (ideally before conception).

in general, it is best not to exclude any foods from the mother’s diet, as breastfeeding is intended to create tolerance. In general, it is also best to exclude from the diet of the pregnant woman and breastfeeding mother foods to which she -and/or the biological father of the child – is clearly reactive

Help and support

For further help and support see:


Some babies are sensitive to allergens in breast milk that come from the mother’s diet. Following an elimination diet involves avoiding any foods containing the most likely or known allergens so that these allergens can be eliminated from breast milk.

Information in this article is not tailored for you and your baby. Always consult with your health professionals for advice that takes yours and your baby’s medical history into account.