Breastfeeding diet: what your body needs

When you’re breastfeeding, your body needs extra nutrients. That’s because your body is working harder to make breastmilk full of nutrients for your baby. But you don’t need a lot of extra energy. So it’s really important to eat a wide variety of foods every day from the five main food groups:

  • vegetables – 7½ serves a day
  • fruit – 2 serves a day
  • grain foods – 9 serves a day
  • protein – 2½ serves a day
  • dairy or calcium-enriched products – 2½ serves a day.

If you’re eating a healthy diet, you’ll be getting enough of most nutrients. But there are a few nutrients you need to be aware of – calcium, iodine, vitamin B12 and vitamin D. It’s also important to make sure you’re drinking enough healthy fluids.

Calcium
Calcium makes up an important part of breastmilk and is very important for your baby’s bone development.

You get calcium from:

  • dairy products like milk, cheese and yoghurt
  • calcium-enriched products like some brands of soy milk
  • fish with edible bones, like sardines and salmon
  • tofu
  • some green leafy vegetables like kale and bok choy.

Iodine
Your baby depends on your breastmilk as a source of iodine, which keeps his brain and nervous system developing.

You get iodine from dairy products, seafood, iodised salt and bread made with iodised salt.

Iodine deficiency in breastfeeding mothers can be a risk for babies. So when you’re breastfeeding, it’s recommended that you take an iodine supplement of 150 micrograms (μg) per day. If you have any pre-existing thyroid problems, check with your doctor before taking a supplement.

Vitamin B12
Your baby gets vitamin B12 from your breastmilk. Vitamin B12 is very important for your baby’s developing nervous system.

You get vitamin B12 from meat, fish, eggs, milk and fortified breakfast cereals.

If you follow a restricted diet, particularly a vegan diet, you need to be extra careful about making sure you get enough vitamin B12. You might need a supplement. Your GP or a dietitian can help you work out what you need.

Vitamin D
Your baby depends on your breastmilk as a source of vitamin D. Vitamin D helps your baby absorb calcium, which she needs for bone growth and development.

Your body makes most of the vitamin D you need when you get enough direct sunlight on your skin. There are small amounts in oily fish, fish liver oils, egg yolks and butter.

You might be at risk of vitamin D deficiency if you’re dark-skinned, if you keep all of your skin covered or if you rarely go outdoors. If you’re deficient, you and your baby might need to take a vitamin D supplement. Your GP or a dietitian can help you work out what you need to do.

Fluids
Your body needs slightly more water when you’re breastfeeding. You should aim to have around nine glasses of fluids a day. But you might need more on hot or humid days or if you’re very active.

If you’re not sure whether you’re getting enough fluids, have a look at your urine. It should be pale yellow. Dark yellow urine is a sign that you need to drink more fluids.

Water is the cheapest and healthiest drink. Avoid soft drinks, fruit juices, flavoured milk, flavoured water, sports drinks and energy drinks.

Some women worry about losing their ‘baby weight’. The best way to get back to a healthy weight after pregnancy is by breastfeeding, eating healthy food and doing gentle exercise. Crash or fad diets aren’t good ways to lose weight, because you’ll miss out on important nutrients.

Foods to limit in a breastfeeding diet

Caffeine
Caffeine transfers into breastmilk, so avoid drinking large amounts of caffeinated drinks like tea and coffee. Newborns are especially sensitive to caffeine.

A moderate amount of caffeine is usually fine – about two cups of coffee or three cups of tea a day. You could also try things like non-caffeinated and herbal teas or decaffeinated coffee instead.

If your baby is restless or has difficulty sleeping, you could try limiting how much caffeine you have and see whether this helps.

‘Sometimes’ foods
Keep ‘sometimes’ foods to a minimum. These foods are high in salt, saturated fat and sugar, and low in fibre and nutrients.

Excluding potential allergy-causing foods while you’re breastfeeding won’t reduce the risk of your baby developing allergies. In fact, avoiding too many foods can be dangerous, because your baby won’t get important nutrients.

Alcohol, smoking, medication and breastfeeding

A lot of what you eat, drink or smoke is passed through your breastmilk to your baby and can affect your baby’s brain development.

If you’re breastfeeding, it’s best not to drink alcohol, smoke or use drugs, including marijuana.

But if you plan to have a drink, it’s best to limit the amount to one drink. And wait 2-3 hours (per drink) before breastfeeding again.

Even if you smoke, breastfeeding is still the best option for your baby. You can protect your baby by always smoking outside, and not smoking for an hour before feeding.

Smoke gets trapped on your hair, clothing and skin. So when you’re smoking, cover your hair and clothes with something your baby won’t come into contact with. And you should also wash your hands and brush your teeth after each time you smoke.

Make sure other people smoke well away from you and your baby too.

If you need to take drugs or medication, check with your doctor or pharmacist about what medications are safe while breastfeeding, and about the timing of medications around breastfeeds.

Exercise and breastfeeding

It’s important to allow your body to recover after birth, but when you’re ready, some regular exercise will boost your health and wellbeing.

Being active every day:

  • strengthens your bones
  • reduces your risk of heart disease, cancer and type-2 diabetes
  • controls your weight
  • improves your sleep
  • reduces your stress levels
  • improves your mental wellbeing.

You can begin with gentle exercise like walking, and then try activities like swimming, yoga or Pilates.

Moderate exercise won’t affect your breastmilk, your supply, the amount of nutrients in your breastmilk or your baby’s growth.

Some women worry that exercising will lead to too much lactic acid in their breastmilk. But this happens only after exercising at a very high intensity, and extra lactic acid in your breastmilk won’t harm your baby anyway.

Talk with your doctor or physiotherapist about the right exercise for you.

It can be hard to find the time to fit exercise in, but you can try making it part of everyday activities – for example, pushing your baby’s pram to the shops to pick up some things for dinner gets you out of the house and keeps you active too. You could learn a few exercises to do from home, or use exercise apps or YouTube videos.