Breastfeeding nutrition comes with a lot of conflicting advice. Some sources list dozens of foods to avoid; others say eat whatever you like. The truth, as usual, lies somewhere in the middle - and it's more straightforward than the worry-inducing lists suggest.
The good news: for most breastfeeding mothers, a normal varied diet is absolutely fine. Your body is remarkably efficient at producing quality breast milk even when your own nutrition isn't perfect. That said, a few things genuinely matter.
Increased Nutritional Needs
Breastfeeding is metabolically demanding - you're producing 750-1,000ml of milk daily. This requires:
What Your Body Needs Extra
- ~500 extra calories daily - More than during pregnancy. Many breastfeeding mothers feel genuinely hungry; this is why.
- Increased fluids - Thirst increases significantly. Keep water accessible throughout the day.
- Vitamin D - 10mcg (400IU) daily supplementation is recommended by the NHS throughout breastfeeding.
- Omega-3 fatty acids - DHA passes into breast milk and supports baby's brain development. Oily fish twice weekly, or a supplement if you don't eat fish.
- Iodine - Often overlooked. Dairy, fish, and eggs are good sources. Important for baby's thyroid development.
- Calcium - Your body will draw from your bones if dietary intake is inadequate.
Foods That Actually Need Limiting
Despite the long lists you'll find online, only a few things genuinely require attention:
Caffeine
About 1% of caffeine passes into breast milk. This sounds small, but babies metabolise caffeine very slowly - especially newborns. A cup of coffee for you might mean a restless baby for hours.
- Limit: 200mg daily (roughly 2 cups of coffee, or 4 cups of tea)
- Watch for: Baby seems jittery, irritable, or won't settle after feeds
- Note: Caffeine metabolism improves as babies get older. What affects a newborn may be fine at 6 months.
Alcohol
Alcohol does pass into breast milk at roughly the same concentration as your blood alcohol level. However, occasional light drinking is generally considered compatible with breastfeeding:
- Occasional drink: One or two units occasionally is unlikely to harm your baby
- Timing: Alcohol levels peak in breast milk 30-60 minutes after drinking. If possible, feed before drinking or wait 2-3 hours per unit consumed.
- "Pump and dump": This doesn't speed up alcohol clearance from milk - it clears as it clears from your blood. But expressing can relieve discomfort if you're waiting to feed.
- Regular heavy drinking: This is harmful and should be avoided.
High-Mercury Fish
Mercury accumulates in certain large, predatory fish and passes into breast milk:
Limit These Fish
- Shark
- Swordfish
- Marlin
- Fresh tuna (canned is lower mercury - safe up to 4 cans weekly)
Other fish - salmon, sardines, mackerel, cod, haddock - are not only safe but beneficial. Aim for 2 portions weekly for omega-3s.
Foods You DON'T Need to Avoid
Many traditional "avoid" lists include foods with little or no evidence of harm:
Spicy Foods
These flavour your breast milk slightly but don't harm your baby. Studies show babies whose mothers eat varied diets may be more accepting of diverse flavours later. Unless your baby specifically reacts, enjoy what you normally eat.
Garlic & Onions
Same as above - they change the flavour of milk but aren't harmful. Some babies seem to like the variety; others might be temporarily fussy. Observe your baby, but don't pre-emptively restrict.
Chocolate
Contains small amounts of caffeine and theobromine. In normal amounts (a few squares), it's fine. Only restrict if you notice your baby is unusually unsettled after you eat it.
Eggs, Peanuts, Dairy
Current evidence suggests avoiding allergens during breastfeeding does NOT prevent allergies in your baby. Only avoid if your baby shows signs of reaction (see below) or if advised by a doctor.
Signs Your Baby Is Reacting to Something
True food sensitivities in breastfed babies are uncommon, but they do happen. Signs include:
- Unusual fussiness or crying after feeds (beyond normal)
- Mucus or blood in nappy
- Eczema or skin rashes
- Diarrhoea or constipation
- Congestion or wheezing
- Refusal to feed
If You Suspect a Reaction
Cow's milk protein is the most common culprit in genuinely reactive babies. If you suspect this, speak to your GP or health visitor before eliminating dairy. Proper diagnosis matters - unnecessary restriction is difficult and may affect your own nutrition.
Common Myths Debunked
Myth: Gassy Foods Make Your Baby Gassy
"Avoid beans, cabbage, and broccoli or your baby will have wind."
The gas-producing compounds in these foods (oligosaccharides) aren't absorbed into your bloodstream and therefore don't appear in breast milk. Your digestion and your baby's are separate systems.
Myth: You Need to Drink Milk to Make Milk
"Drink lots of cow's milk to increase breast milk supply."
Your breast milk production is driven by demand (baby feeding) and hormones, not by what you drink. Dairy is a good calcium source, but it doesn't boost supply. Water and other fluids are what you need for hydration.
Myth: Certain Foods Increase Milk Supply
"Eat oats, fenugreek, or brewer's yeast to boost supply."
There's no robust evidence that any food increases milk supply. What does help: frequent feeding, proper latch, adequate rest, and sufficient hydration. The best galactagogue is a feeding baby.
Practical Eating Strategies
When you're sleep-deprived and holding a baby much of the time, elaborate meals aren't realistic:
- One-handed foods: Prepare snacks you can eat while feeding - nuts, cheese, fruit, pre-made sandwiches
- Batch prep when possible: Cook larger portions when you can, refrigerate extras
- Accept help: Let people bring you meals. This is not the time to be self-sufficient.
- Ready meals aren't cheating: A balanced ready meal beats skipping lunch because you're too tired to cook
- Keep water everywhere: Every room you breastfeed in should have a drink accessible
Key Takeaway
Breastfeeding nutrition is simpler than it's often made out to be. Eat a varied diet, limit caffeine to 200mg daily, be sensible with alcohol, and take vitamin D. Beyond that, only restrict foods if YOUR baby specifically reacts to them - not because a list told you to. Trust your body, observe your baby, and eat enough to support both of you.
References
- NHS. (2024). Breastfeeding and diet.
- Jeong, G. et al. (2017). Maternal food restrictions during breastfeeding. Korean Journal of Pediatrics
- Martin, C.R. et al. (2016). Review of Infant Feeding: Key Features of Breast Milk and Infant Formula. Nutrients
- Academy of Breastfeeding Medicine. (2018). ABM Clinical Protocol #9: Use of Galactogogues
- Scientific Advisory Committee on Nutrition. (2023). SACN Vitamin D Guidelines
