Best Breastfeeding Diet and Foods to Avoid

There are several foods to avoid eating during pregnancy from liver to certain types of fish or soft cheese 1. But what about when you are breastfeeding? Are there any foods to avoid while breastfeeding? What is the best breastfeeding diet? This article answers frequently asked questions about diet and breastfeeding.

Are there any foods to avoid while breastfeeding?

Unlike during pregnancy a breastfeeding mother can eat and drink most things and there aren’t any specific foods to avoid. It’s advisable to have a nutritious balanced diet because that is healthier for you, your milk supply and perhaps even your baby’s food preferences in the future—but generally you can eat your usual pre-pregnancy diet while you are breastfeeding.

What about baked beans, cabbage or spicy food…?

You may hear stories that you can’t eat certain food items when you are breastfeeding because they will give your baby tummy ache or wind (gas). Occasionally a baby may be sensitive to a particular food, but there’s no need to restrict your diet just in case.

Can my diet affect the amount of breast milk I can make?

The volume of breast milk you can make is controlled by how frequently and efficiently the breasts are emptied either by a baby or a pump. What you eat and drink isn’t thought to substantially affect the amount of milk your body can make however certain foods and herbs may help to build a milk supply see What is a Galactagogue? Author Hilary Jacobson believes a very poor diet can affect breast milk supply and composition 2.

Low milk supply

If you do have a low milk supply or a baby who is not gaining the expected weight contact an IBCLC lactation consultant or other breastfeeding specialist to help you and see How to Make More Breast Milk.

Can diet affect the quality of my breast milk?

Generally an average diet will guarantee nutritious breast milk. The authors of The Womanly Art of Breastfeeding explain:

Eating more won’t make more milk, and not eating enough won’t make less milk. You don’t need a perfect diet to keep your milk nutritious. Your milk is made from your blood. If you haven’t been worrying about the quality of your blood lately, there’s no need at all to worry about the quality of your milk!

However, maternal diet can affect breast milk in the following ways:

  • Micronutrients in breast milk. If a mother is severely malnourished or if certain nutrients eg vitamin D, iodine or vitamin B12 (see below) are low or missing in her diet this could affect the balance of micronutrients in breast milk3.
  • Breast milk flavour. Traces of a mother’s diet pass into breast milk and the milk is said to adopt the flavour of the food that the mother has eaten. This allows a breastfed baby to gradually become accustomed to family table foods and may help baby to accept a wide range of familiar tastes when solids are started.
  • Food allergens. Breast milk can contain traces of food and occasionally a baby may be intolerant to something passing into a mother’s milk. Typically this will be a common allergenic food such as cows’ milk protein. See Milk Allergy in Babies for more information.
  • Types of fatty acids. There are over 200 fatty acids (types of fat) in breast milk. While some fatty acids are made within the breast, others come from the mother’s diet eg omega-3 fatty acid docosahexaenoic acid (DHA) and omega-6 fatty acid arachidonic acid (AA). DHA and AA are essential fatty acids that are very important for the baby’s developing brain, eyes and nervous system. The mother’s diet influences the proportions of fatty acids in breast milk 4. Fatty acid composition may also influence the breast milk microbiome (the microorganisms in breast milk)5.

Although there may be small differences in the composition of human milk it is still far superior to industrially made formula milk which has many missing ingredients and potential allergens. See Is There a Difference Between Breast Milk and Formula? for more reading.

What if my diet is mostly junk food?

A junk food diet is one that is high in calories due to high fat and/or high sugar content. Some breastfeeding authors state that eating a junk food diet will still produce good quality milk6. Others question whether a diet of mostly junk food could predispose a baby to preferring junk food later in life78.

Should I avoid allergenic food?

There are currently no recommendations to avoid typically allergenic foods such as nuts or fish during breastfeeding unless the mother is herself allergic to something that she needs to avoid 910.

Allergy author Maureen Minchin summarises:

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

Can I eat peanuts while breastfeeding?

Yes, unless you know you are allergic to peanuts. The UK’s National Health Service (NHS) advises:

If you’d like to eat peanuts or foods containing peanuts, such as peanut butter, while breastfeeding, you can do so as part of a healthy, balanced diet (unless, of course, you are allergic to them).
There’s no clear evidence that eating peanuts while breastfeeding affects your baby’s chances of developing a peanut allergy. If you have any questions or concerns, you can talk to your GP, midwife or health visitor.

Can I eat fish while breastfeeding?

Fish is a good source of essential fatty acids for the breastfeeding mother however some types of seafood contain high levels of mercury due to marine pollution. Pregnant and breastfeeding mothers are advised to limit their potential exposure to mercury as it is particularly dangerous in the early stages of a baby’s development. The UK’s National Health Service recommends breastfeeding women eat no more than one portion of shark, swordfish and marlin per week and no more than two portions of oily fish a week. There is no limit on canned tuna 11.

My baby seems fussy, is it something in my breast milk?

There are several reasons why a breastfed baby can appear fussy so it is worth looking into these with your breastfeeding specialist or health professional before assuming something in your diet is the cause. Sometimes however, a baby can be sensitive or intolerant to particular foods which may cause them to fuss or have tummy ache. Other symptoms may be apparent such as eczema, reflux, rashes, being snuffly, copious runny poop and/or mucous in the poops.

Food intolerances

If your baby seems to be particularly fussy or uncomfortable after something specific you have eaten, try avoiding that food for a while to see if the symptoms settle down. A common culprit triggering a reaction is dairy produce in the mother’s diet see Milk Allergy in Babies for more information. And see Elimination Diet for more information about cutting out problem food. In a discussion paper, Lindsey Hurd Reeves, researcher and IBCLC, reviews the relationship between maternal diet, a healthy immune system and a healthy microbiome and speculates how mother and baby’s gut function might be improved to reduce food sensitivities and allergy12.

Can I drink coffee or caffeine?

Yes, a few cups of coffee won’t normally upset your baby when you are breastfeeding. However caffeine does get into breast milk and can be difficult for a baby to metabolise (get rid of) especially in the first few weeks of his life. If you drink a lot of coffee, watch out for signs that your baby is particularly wakeful or jittery and read more about recommended daily limits in our article Coffee, Caffeine and Breastfeeding.

Can I drink alcohol while breastfeeding?

Small amounts of alcohol while breastfeeding do not pose a problem for your baby see Breastfeeding and Drinking Alcohol for recommended limits.

Can I take medications when breastfeeding?

Lots of medications are compatible with breastfeeding. For resources to check the compatibility of medicines see Medications and Breastfeeding.

Do I need to eat extra food while breastfeeding?

During the first four to six months of his life a baby will double his birthweight on breast milk alone. Your metabolism efficiently handles this energy requirement by using the fat stores laid down in pregnancy alongside eating around 500 extra calories a day 13. Women who are very underweight or malnourished with no fat stores will need to eat more.

Do I need to drink a lot of water?

You will probably find you are more thirsty than usual while breastfeeding. Drinking just enough fluid to quench your new thirst and ensure your urine is pale coloured will keep you well hydrated and provide enough liquid to make plenty of breast milk. There’s no need to drink huge amounts of extra water (or other drinks such as cows’ milk) to increase the amount of breast milk you make 14151617. Breast milk volume is increased by efficient and continual breast emptying, not by how much fluid you drink. One study by Dusdieker (1990) suggested drinking 25% more fluids than baseline may even reduce the volume of breast milk slightly.

You don’t need more fluids than you want in order to make milk, and your supply won’t decrease if you’re mildly dehydrated. If your urine is medium to pale yellow, then you’re doing fine. Oxytocin release can make you suddenly thirsty (carrying a water bottle helps).

How do the fats in my diet affect my breast milk?

As discussed above in “Can diet affect the quality of my breast milk?” a healthy balance of essential fatty acids such as DHA and AA in a mother’s diet are important for a baby’s developing brain, eyes and nervous system. Fatty acid composition can also influence the breast milk microbiome. Koletzko et al18 found that some of the fat content of breast milk also comes from the mother’s body stores which will have been shaped by her past diet.

The variation in types of fatty acids is not thought to alter the total fat content in milk, so even mothers on a low fat diet could provide enough fats in breast milk19 20. However, Mohammed et al found in one small study that a reduced calorie, higher fat diet increased the milk fat, energy content of milk and so a baby’s energy intake:

In conclusion, under moderate calorie restriction, milk production was not affected by maternal diet composition. Milk fat, energy content, and infant energy intake were higher during the [moderately high fat, controlled calorie] diet

Fat in breast milk

Irrespective of diet, the fat content of breast milk varies during a single breastfeed and between feeds and breasts. Feeding on demand, and letting baby finish the first breast before offering the second, helps a breastfed baby get the milk (and fat) they need over a 24 hour period. Forget About Foremilk and Hindmilk has more information about how the fat content changes during a feed. If a baby isn’t gaining weight see How to Make More Milk and Baby Not Gaining Weight.

Research on fatty acids and maternal diet

Research is still discovering the importance of healthy fats in a mother’s diet:

  • Inflammation. One author discusses how an excess ratio of omega 6 fatty acids (found in many processed foods) compared to omega 3 fatty acids in a mother’s diet may be associated with inflammation including irritable bowel disease and recurrent mastitis (Hurd Reeves, 2015).
  • Risk of disease. Researchers are looking into associations between the type of fats consumed in the mother’s diet, their metabolism, and the child’s risk of diabetes, asthma, eczema (Wilson, 2018).

Can I breastfeed if I am underweight?

Very underweight mothers may have breast milk with low levels of some nutrients and fat but unless the mother is significantly malnourished she can often still make enough milk 21. Improving the mother’s diet and vitamin status will raise the vitamin levels in breast milk.

Because micronutrient levels are quickly reflected in breast milk, renourishment of the woman is effective for mother and infant. It is less expensive and safer to nourish the mother than it is to give the infant artificial baby milk

Very underweight mothers will not have substantial fat stores to draw on for the additional calorific demands of breastfeeding and may need more calories from their diet.

Can I breastfeed if I am overweight?

With good help from your IBCLC lactation consultant breastfeeding will have the best chance to get off to a good start whatever your size. Problems for overweight mothers can include:

  • Breast milk can be later “coming in” when a mother is overweight with a pre-pregnancy BMI above 26.
  • An overweight mother may have a low milk supply due to a lower prolactin response 2223.
  • The underlying causes for obesity (BMI above 30) may also be associated with low milk supply e.g. polycystic ovary syndrome or hyperthyroidism or a mother may suffer from insulin resistance or diabetes which can affect milk supply.
  • Studies have found obese mothers are less likely to breastfeed 24.
  • Overweight mothers may be at risk for nutrient deficiencies if they consume a very poor diet.
  • Animal studies indicate that maternal obesity and overeating of calorie rich foods could be associated with a higher risk of obesity and type 2 diabetes in the offspring25.

Do I need to take breastfeeding vitamins or supplements?

In most cases if you are eating a healthy diet you will be getting all the vitamins and minerals you need and your body will automatically add these to your breast milk in just the right amounts. However, certain deficiencies can creep in with some diets and lifestyles for example:

Vitamin D

Vitamin D is made in the body following exposure of the skin to sunlight and a little comes from our diet. Some people are deficient in this vitamin due to lack of sunlight and it is hard to get enough from diet alone. Check our article Vitamin D and Breastfeeding for current recommendations on supplements for you and your baby.

Vitamin B12

Vegan diets and some strict vegetarian diets may not have enough natural sources of vitamin B12. Mothers on these diets may need to check their vitamin status or take supplements so that their babies will be sure to get enough vitamin B12 via their breast milk. Babies deficient in vitamin B12 may fail to thrive, be lethargic, have a developmental delay or have certain types of anaemia which require urgent treatment. Vitamin B12 deficiency is also a possibility for mothers who have had surgery to reduce the size of their stomachs (bariatric surgery).


Iodine is a trace element found in sea food, cereals and grains which helps to make thyroid hormones. Levels of iodine in plants vary, depending how much iodine is available in the soil 26. As some diets can be low in iodine, some countries recommend routine iodine supplementation for breastfeeding mothers 2728. Smoking can reduce iodine levels in breast milk even further 29 increasing the risk of iodine deficiency-induced brain damage.

In the UK the Association of UK Dietitians has produced a fact sheet on iodine discussing when supplements are needed during pregnancy and breastfeeding and the levels recommended. Consult with your health care professional whether iodine supplements are recommended where you live.


For further information about iron levels in breast milk and in which situations your baby’s iron levels might be low, see Iron in Breast Milk. Taking supplements won’t increase iron levels in breast milk but a low iron status for mother could be linked with low milk supply.

Should I take a multivitamin while breastfeeding?

Abe et al, 2016 30 have reviewed the effects of vitamin supplements and found there was insufficient evidence to make a recommendation and that further studies were needed. In the UK the NHS recommends taking vitamin D supplements but says other vitamins and minerals can be obtained by a varied and balanced diet31.


There are no strict rules to follow for a breastfeeding diet and there are no particular foods to avoid during breastfeeding. Great breast milk will be made to order by the breast using a less-than-perfect diet and a mother’s body stores. Mothers could check with their health care professionals if they have any concerns that their diet may be low in any specific vitamins or nutrients. New research into the role of essential fatty acids in breast milk highlights the value of healthy fats in the maternal diet. Occasionally a baby will react to something in his mother’s diet and she can then avoid that food for a while.