You have a baby. You start breastfeeding.
And suddenly everyone has an opinion about your lunch.
Don't eat spicy food. Avoid garlic. Definitely no broccoli. Drink more milk to make more milk. Eat oats for supply. Cut out dairy if the baby is windy. Have a special tea. Avoid coffee. Actually, have coffee because you haven't slept since Tuesday.
Breastfeeding comes with an impressive amount of unsolicited nutritional advice.
So can what you eat affect your breast milk?
Yes, but probably not in the simple “you ate cabbage, therefore your baby has wind” way you may have been led to believe.
Research shows that maternal diet can influence some components of breast milk more readily than others, particularly its fatty-acid profile and concentrations of certain micronutrients. Other components appear considerably less responsive to what you ate for dinner.[1]
And for most breastfeeding parents, there is no need to follow a restrictive “breastfeeding diet” or routinely avoid particular foods.[2]
So before you reluctantly remove garlic, coffee, curry and everything else worth getting out of bed for, let's look at what we actually know.
Do you need a special diet when breastfeeding?
Generally, no.
The NHS advises that you do not need to follow a special diet while breastfeeding. Instead, the recommendation is much less exciting: eat a healthy, varied diet.[2]
That means fruit and vegetables, carbohydrates, sources of protein, dairy or suitable alternatives, and a variety of foods that provide the nutrients and energy your body needs.
The US Centers for Disease Control and Prevention (CDC) similarly states that breastfeeding mothers generally do not need to avoid or limit specific foods and should be encouraged to eat a healthy, diverse diet.[3]
So there is no official breastfeeding menu consisting exclusively of porridge, steamed vegetables and foods that your mother-in-law has personally approved.
Thank goodness.
Does what you eat actually change your breast milk?
This is where things get interesting.
Breast milk is extraordinarily complex. It contains fats, proteins, carbohydrates, vitamins, minerals, hormones, enzymes, immune components and numerous other substances.
And your diet does not affect all of those components in the same way.
A 2024 systematic review examining maternal diet and human milk composition found the strongest body of evidence for an association between diet and the fatty-acid composition of breast milk. Maternal fish intake, for example, was associated with higher concentrations of certain omega-3 fatty acids in milk.[1]
For carbohydrates, proteins, vitamins and minerals, the available studies were fewer and results were more variable.[1]
A more recent review published in 2026 similarly concluded that the protein and carbohydrate content of breast milk tends to be relatively resistant to maternal nutritional status, while the fatty-acid profile and concentrations of certain vitamins and minerals can be influenced by maternal diet and nutritional status.[4]
In other words, breast milk isn't simply a liquid version of yesterday's dinner.
Eat more protein and your milk doesn't automatically become a high-protein shake.
Have chips for lunch and your baby isn't suddenly receiving chip-flavoured milk.
The relationship between diet and milk composition is considerably more sophisticated.
Can flavours from food enter breast milk?
Your diet can influence more than nutrients.
Volatile compounds from foods and drinks can reach breast milk and may temporarily influence its aroma or flavour.
That isn't necessarily a problem.
In fact, exposure to different flavours through breast milk has been investigated as one of the ways breastfed babies may become familiar with flavours from the family diet.
So if your breast milk smells slightly different after you have eaten garlic, this does not mean you've ruined it.
Your baby has not submitted a complaint to the chef.
Do you need to avoid spicy food while breastfeeding?
For most people, no.
There isn't a general recommendation to avoid chilli, curry, garlic or other strongly flavoured foods simply because you're breastfeeding.
If these foods are a normal part of your diet, you generally don't need to start eating a deliberately bland diet after giving birth.
Different cultures around the world eat very different diets while breastfeeding.
Babies have somehow survived humanity's extensive relationship with seasoning.
If you notice a consistent pattern where your baby appears uncomfortable after you eat a particular food, you can discuss it with your GP or health visitor. But one unsettled afternoon after you ate a curry does not establish that the curry was responsible.
Babies, inconveniently, can be unsettled for approximately 4,783 different reasons.
Does eating “gassy” food make your baby gassy?
Broccoli. Beans. Cabbage. Lentils.
They can give you wind.
That doesn't mean the gas travels through your bloodstream, enters your breast milk and is delivered directly to your baby.
Gas in your digestive tract doesn't pass into breast milk.
Components of foods can enter breast milk, but that is a completely different biological process.
So you generally don't need to avoid nutritious foods such as beans or cruciferous vegetables simply because somebody told you they'll give the baby wind.
If your baby has persistent digestive symptoms, excessive crying, vomiting, diarrhoea, constipation, poor weight gain or other symptoms that concern you, that's worth discussing with a healthcare professional rather than embarking on an increasingly miserable elimination diet.
What about dairy?
This is where the conversation becomes more nuanced.
You do not routinely need to stop eating dairy because you're breastfeeding.
However, proteins from foods consumed by the breastfeeding parent can pass into breast milk in small quantities, and some babies can react to particular food proteins.
Cow's milk protein allergy can occur in breastfed babies, although it is more commonly encountered when formula or solid foods containing cow's milk are introduced. Possible symptoms can include skin reactions, gastrointestinal symptoms and worsening eczema.[5]
If cow's milk protein allergy is suspected, speak to your GP or another appropriately qualified healthcare professional.
Don't simply remove dairy from your diet because your baby was windy on Wednesday.
Unnecessary elimination diets can make it harder to meet your own nutritional needs. If you do need to exclude dairy, professional dietary advice can help ensure you're getting enough nutrients such as calcium and iodine.
The important bit: Food elimination should have a reason, rather than becoming another breastfeeding endurance test.
Do you need to avoid peanuts and other allergens?
Generally, no.
The NHS advises that people who are pregnant or breastfeeding do not need to avoid foods that commonly cause allergic reactions, including peanuts, unless they themselves are allergic to them.[6]
So eating peanut butter while breastfeeding does not automatically increase your baby's risk of developing a peanut allergy.
There is no need to pre-emptively remove eggs, nuts, dairy, wheat or other common allergens from your diet without a medical reason.
If your baby has symptoms that suggest an allergy, however, speak to a healthcare professional.
That's a different situation from avoiding foods “just in case”.
Can caffeine get into breast milk?
Yes. Caffeine can pass into breast milk in small amounts.[2][3]
And babies, particularly very young babies, process caffeine more slowly than adults.
This means large amounts of caffeine may contribute to symptoms such as restlessness or difficulty sleeping in some babies.
Current NHS breastfeeding guidance recommends having no more than 200 mg of caffeine per day.[2]
Remember that caffeine isn't only hiding in coffee.
It's also found in:
- tea
- cola
- energy drinks
- chocolate
- some medicines.[2]
You don't necessarily need to break up with coffee entirely.
Which is fortunate, given the whole newborn-not-sleeping situation.
But it is worth keeping an eye on your total caffeine intake and noticing whether your baby appears particularly sensitive to it.
What about alcohol and breast milk?
Alcohol passes into breast milk.
The safest option while breastfeeding is not to drink alcohol. However, NHS guidance states that an occasional drink is unlikely to harm your baby, particularly if you leave time between drinking and breastfeeding.[7]
Alcohol levels in breast milk rise and fall alongside alcohol levels in your bloodstream.
This also means that “pumping and dumping” does not make alcohol leave your milk faster. Expressing can be useful for comfort or maintaining your feeding routine, but alcohol disappears from breast milk as it disappears from your bloodstream.[7]
The NHS advises allowing approximately two to three hours per drink before breastfeeding.[7]
There is another important safety issue here: you should never share a bed or sofa with your baby if you have been drinking alcohol, because of the association with sudden infant death syndrome (SIDS).[7]
Does drinking more water make more breast milk?
Hydration matters for your own health.
But forcing yourself to drink enormous quantities of water isn't a magical milk-supply hack.
Drink according to thirst and make sure you have easy access to fluids, especially since breastfeeding can make you feel thirsty.
A water bottle permanently attached to your person may become part of your new personality.
That is fine.
You don't need to turn hydration into competitive sport.
Can certain foods increase milk supply?
Welcome to the world of galactagogues.
This term refers to substances used with the intention of increasing breast milk production. Depending on which corner of the internet you've wandered into, you may encounter oats, fenugreek, fennel, brewer's yeast, milk thistle, special biscuits, herbal teas and an alarming number of supplements marketed for milk supply.
Some traditional remedies have been used for generations.
Some have also been researched.
But evidence that particular foods or herbal products reliably increase milk supply is often limited, and herbal products can have side effects and interactions.
More importantly, perceived low milk supply can have many causes.
If you're concerned about milk production, it is much more useful to have feeding and milk transfer assessed by somebody appropriately qualified than to spend £37 on biscuits containing fenugreek and hope for the best.
What actually affects milk supply?
Milk production is strongly influenced by milk removal.
In simplified terms, regular and effective removal of milk from the breast signals continued production.
That means concerns about milk supply often need to look at the whole feeding picture rather than just diet.
Factors such as how frequently your baby feeds, how effectively they transfer milk, latch, expressing practices and certain medical circumstances can all be relevant.
And importantly, things that are often interpreted as proof of low supply aren't necessarily proof at all.
A baby wanting to feed frequently does not automatically mean you aren't producing enough milk.
Neither does your breast feeling softer than it did last week.
Neither does being unable to pump a particular quantity.
If you're worried about supply, seek breastfeeding support rather than trying to solve it entirely through your shopping list.
Does eating more make more milk?
Breastfeeding requires energy, and your nutritional requirements can increase during lactation.
The CDC estimates that well-nourished breastfeeding mothers generally require approximately 330 to 400 additional kilocalories per day compared with what they consumed before pregnancy, although individual requirements vary.[3]
That doesn't mean you need to count calories.
It certainly doesn't mean every breastfeeding person needs exactly the same amount of food.
Appetite is allowed to be information too.
If you're hungry, eat.
Revolutionary wellness advice, we know.
What nutrients deserve particular attention while breastfeeding?
Although you don't need a special breastfeeding diet, certain nutrients are particularly worth considering.
Requirements for nutrients including iodine and choline increase during lactation.[3]
Vitamin B12 deserves particular attention if you eat a vegan diet because animal products are major dietary sources of B12. The CDC notes that babies breastfed by someone consuming no animal products may be at risk of receiving inadequate B12 if maternal status is low.[3]
Omega-3 fatty acids are another interesting example because maternal intake can influence the fatty-acid profile of breast milk.[1][4]
This does not mean you need an enormous supplement stack labelled ULTIMATE BREASTFEEDING MAMA.
It means individual nutritional requirements matter.
If you follow a vegan or highly restrictive diet, have known deficiencies, have difficulty eating adequately or are concerned about your nutritional intake, speak to a doctor, dietitian or other appropriately qualified healthcare professional.
What about herbal tea while breastfeeding?
Herbal tea is another area where the word “natural” can create a false sense of simplicity.
A herbal tea isn't one ingredient.
Peppermint, chamomile, fennel, fenugreek, sage and liquorice are different plants containing different compounds.
Some have long histories of traditional use during breastfeeding. Others have limited lactation-specific safety data. And a concentrated herbal supplement is not necessarily equivalent to drinking an ordinary infusion.
If you're drinking a simple herbal tea occasionally, that's a very different exposure from taking concentrated botanical extracts several times per day.
If you're considering a herbal product specifically because it claims to increase milk supply, check what evidence exists for the actual preparation and dose rather than assuming the plant name on the front of the packet tells you everything you need to know.
Tea is very good at being tea.
It doesn't automatically need a second career in lactation medicine.
Do foods you eat make breast milk “better” or “worse”?
This is perhaps the part of the conversation where we can remove a little unnecessary pressure.
Breast milk isn't graded according to how perfectly you ate that day.
You do not produce “bad milk” because lunch was toast.
You haven't failed nutritionally because there wasn't a leafy green vegetable within a five-metre radius of dinner.
Research does show that maternal nutrition can influence certain aspects of milk composition, particularly fatty acids and some micronutrients.[1][4] But breast milk composition is also regulated by complex physiological processes and does not simply mirror everything you eat.
One recent systematic review concluded that while evidence linking maternal diet with breast-milk fatty acids has grown, research into many other milk components remains limited and methodologically varied.[1]
So yes, eating well matters.
Your health matters too.
But feeding yourself does not need to become another opportunity to achieve maternal perfection.
You have enough going on.
When should you speak to a healthcare professional?
Speak to your GP, health visitor, midwife, paediatrician or appropriately qualified breastfeeding professional if:
- you're worried your baby isn't gaining weight appropriately
- you're concerned about your milk supply
- feeding is painful or difficult
- your baby has persistent vomiting, diarrhoea, constipation or significant digestive symptoms
- you notice blood in your baby's stool
- your baby develops significant or persistent skin symptoms
- you suspect a food allergy
- you're considering a restrictive elimination diet
- you have concerns about your own nutrition while breastfeeding.
If your baby develops signs of a severe allergic reaction, such as difficulty breathing or swelling of the tongue or throat, seek emergency medical attention.[6]
The answer to a feeding problem is not always hidden in your fridge.
