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 challenging 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.

Finding 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. To narrow down likely allergens consider:

  • Keeping a food diary. Keeping a food diary can help to pinpoint offending foods. Try keeping a record of what you have eaten alongside your baby’s behaviour such as fussy behaviour, abnormal nappies, rashes or sleeping disturbances.
  • Completing an allergy questionnaire. With a comprehensive questionnaire it is often possible to identify the most likely allergens that affect mother and baby. Crying Babies and Food: In the early years is a Kindle Book by author Maureen Minchin which includes a sample parent questionnaire.
  • Your location. It may be possible to find likely allergens based on where the baby lives. For example, in some areas, hens’ eggs are a common cause of allergy, whereas in some countries peanuts are a common allergen (ABM, 2011).

Elimination diets

Mothers can try eliminating one allergen at a time to see if there is any improvement or they can follow a low allergen diet (total elimination diet or baseline exclusion diet) from the beginning to improve their babies’ symptoms.

#1 Eliminating one food at a time

The simplest way to do an elimination diet is to try eliminating one food or a group of foods at a time. A mother can reintroduce a food if the baby’s symptoms remain the same and move on to another food to eliminate. However if a baby has severe symptoms this could be a longer route to finding the offending food. The Academy of Breastfeeding Medicine (ABM) protocol for allergic proctocolitis explains:

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, 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.

When eliminating cows’ milk it will be important to include all products made from cows’ milk e.g. cheese, yoghurt, ice cream, and specific protein components like casein, whey, and lactoglobulin (see the next section for help with ingredient labelling). In addition, beef products affect some babies.


#2 The low allergen or total elimination diet

Another approach for an elimination diet is to start with a low allergen diet of only relatively “safe” or non-allergenic foods. Once baby’s symptoms have settled the mother can reintroduce one food group at a time to identify the the foods that provoke a reaction. Places with information on low allergen diets include:

  • Breastfeeding Works! Even With Allergies (book). In this book, lactation consultant Robyn Noble shares foods for a baseline exclusion diet and discusses dietary ground rules and how to avoid common pitfalls.
  • Elimination Diet, Ask Dr Sears, 2017. This website discusses an elimination diet that involves cutting out all potentially allergenic food (such as dairy, beef, eggs, chicken, shellfish, soy, corn, wheat, and peanuts) for two weeks followed by gradually reintroducing food and noticing if there is a reaction.
  • ABM Clinical Protocol #24: Allergic Proctocolitis in the Exclusively Breastfed Infant. The Academy of Breastfeeding Medicine mentions a low-allergen diet of foods like lamb, pears, squash, and rice and recommends consultation with an experienced dietitian.

Tips for elimination diets

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 parents through the various names for allergens include:

  • Tips for Avoiding Your Allergen by Food Allergy Research and Education (FARE)—a guide to help identify hidden allergens in several elimination diets including milk-free, egg-free, wheat-free, soy-free, shellfish/fish-free, and nut free diets.
  • Dairy Elimination Diet 2012 fact sheet on the Infant Proctocolitis website discusses the places to find hidden dairy and the unexpected names used labelling.
  • Soy Elimination Diet is another fact sheet on the Infant Proctocolitis website and includes a list of soy foods, ingredients and places soya can “hide”.
  • Allergy Elimination Diet by Kevin J. Kelly, MD.

Supplements and 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.

Fish oil

When following the baseline exclusion diet, author Robyn Noble advocates supplementation of two 1000mg fish oil capsules after each meal during lactation alongside a daily vitamin and mineral supplement and a flax seed oil supplement8.

Omega-3s and vitamin D

An important aspect of any elimination diet is to address any pre-existing nutritional deficiencies a breastfeeding mother may have because these can affect the allergic status of her baby. Low levels of essential fatty acids (omega-3s rather than omega-6s) and vitamin D in a mother’s diet have been linked with infant allergies. Omega-3s and Vitamin D are both anti inflammatory agents that are important for healthy immune function. Deficiencies in these and excesses of omega-6 fatty acids are risk factors for allergies, autoimmune diseases and cancer. (Noble, 2015)

Health benefits for mothers

There can be notable health improvements for mothers themselves once they begin excluding foods for their babies benefit. Noble reports mothers have reported improved energy levels, and improvements in headaches, acne, ear, nose and throat conditions, chronic infections, chronic inflammatory conditions and autoimmune conditions (Noble, 2015).


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.

Frequently asked questions

Should I go lactose free?

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.

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; Noble, 2015) however it may take two to four weeks to see full improvement9. 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.

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 they can take a full history and rule out any other causes of fussy behaviour.

I’ve tried a careful elimination diet but my baby is no better, what next?

If you have tried an elimination diet for one food group such as dairy with no improvement:

  • Check other allergens. You may need to look at other common allergens in your diet such as corn, wheat, eggs, nuts or soy. One option is to follow a low allergy or total exclusion diet until your baby’s symptoms clear and then gradually reintroduce more food groups and notice if your baby reacts. For some mothers, cutting out caffeine, cigarette smoke and nicotine, artificial colours and flavourings, artificial sweeteners (e.g. aspartame) and preservatives was key. For some, coconut products could be problematic (Noble, 2015). Consider avoiding other allergens like synthetic fragrances, bleach or detergents (including sterilising fluid residues in baby bottles) or oral contraceptives (Minchin, 2015).
  • Be thorough. Check all packaged goods for the hidden food, for example dairy is often labelled as specific proteins like casein or whey (see above). Some mothers have found they needed to eliminate all beef and beef containing products when going dairy free. If baby is still having solids or formula they may be getting allergens directly.
  • Milk substitutes. One pitfall with a dairy elimination diet is that by switching to anther milk e.g. goat’s milk or a soy or nut based milk you may be switching to something that is potentially allergenic in its own right.
  • Heathy diet. One reason for lack of success could be having too much carbohydrate or too many processed foods, insufficient essential fatty acids or low vitamin D in mother’s diet. Noble recommends eating butter (mostly milk fat not milk protein) instead of margarine. (Noble, 2015). Some mothers have found success with specific healing diets for their own gut health10.
  • Not an allergy? Your health professional and IBCLC lactation consultant can help rule out other causes for your baby’s symptoms that may have nothing to do with your diet and discuss next steps.

Should I reintroduce 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 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 11 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

Where can I find more 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.