Breastfeeding and your diet

You don’t need a 'perfect' diet for breastfeeding. In general, your diet is important for your own health and energy levels, rather than affecting your breastmilk and your baby.

Even in countries where there isn’t much food, mothers are able to breastfeed and their babies do well. However, there are a few nutrients a baby needs that may be affected if the mum's intake is too low, such as iodine and vitamin B12. 

When you are breastfeeding, your body needs more nutrients but it also uses what you take in more efficiently. And you may have an increased appetite too.  

You can get the extra energy and nutrients you need by:   

• eating slightly more of the same foods you would normally eat,  

• using up some of the fat stores your body laid down while you were pregnant and  

• by reducing the amount of energy you use. 

For mothers eating a normal Australian diet, the most common nutrients that may run low are iodine, iron and calcium. Talk to your doctor or a dietitian to find out if you have enough of these in your diet. In the case of iodine, you may be advised to take a supplement, as the amounts recommended for pregnant and breastfeeding mothers are hard to get from a normal Australian diet.

For more information about iodine needs, see the National Health and Medical Research Council publication Iodine supplementation for Pregnant and Breastfeeding Women. 

Making breastmilk uses extra fluid, so breastfeeding mums are often more thirsty than usual. There is no set amount that you need to drink, as it depends on the weather, your activity level and the foods you eat. Be guided by your thirst; don't be tempted to ignore it because you are busy.  

You could make it part of your breastfeeding routine to have a glass of water or a water bottle next to you each time you give your baby a feed. Carrying a water bottle when you're out and about also makes it easy to have a drink when you need it.  

Special diets

There are two types of vegetarian diets: 

• Diets that include some animal products, such as dairy products and/or eggs, and in some cases fish or some other animal products. 

• Diets that don’t contain any animal products (vegan). 

The main nutrients that you have to worry about if you don't eat (or eat only a small amount of) animal products are protein, iron, calcium, vitamin B12 and omega-3 fatty acids. While you are breastfeeding, a well-planned vegetarian diet can satisfy these needs, except perhaps for vitamin B12 in a vegan diet.   

If you have followed a vegan diet for years before having your baby, it would be wise to have your vitamin B12 levels checked. You may need a vitamin B12 supplement.  

Check with your doctor or a dietitian if you aren't sure whether your diet has enough nutrients for both yourself and your baby. 

Some mums have a dairy-free diet because in their culture, they don‘t traditionally eat dairy products. Other mums are dairy-free because they or their babies react to cow's milk. Either way, these mums need to get their calcium from other foods. Dairy products are mainly eaten to supply calcium in the Western diet, but they are also a valuable source of protein and some vitamins like A, B2 (riboflavin) and B12.  

When you don’t eat dairy products, you need to get all these nutrients from other foods. A dietitian can advise on this for your individual situation, taking into account your cultural background. 

If you have food allergies, or a medical condition such as coeliac disease, you will need a special diet. As long as these conditions are well managed, there should be no reason why you can't breastfeed. 

Breastfeeding may help to protect your baby against also having these conditions as they grow up. Your diet can be well balanced and nutritionally complete for both you and your baby. If you are unsure whether your diet is good enough, a dietitian can help assess and advise you. 

Some babies can be food-sensitive and react to tiny amounts of foods that come through their mum's breastmilk. This can include allergies and food intolerances. The most common food allergies in babies are those to cow's milk, soy, wheat, eggs, peanuts and tree nuts. A baby can also have food intolerance (along with an allergy or alone) and react to a range of other foods in the mother's diet. Read more about breastfeeding and food intolerances. 

However, there are many reasons a baby may be unsettled or have other symptoms similar to those of food intolerance. Seek professional advice to help you work out if your baby is food-sensitive. Each mother and baby pair is different.   

Even if you are sure that it’s something in your diet, it can often be very difficult to work out which foods are causing problems. Cutting out a whole food group, such as dairy products, may make it harder for you to eat a balanced diet. A dietitian will be able to help you sort out what the problem foods are and ensure that your diet contains all the nutrients you need. 

Having no alcohol altogether while pregnant or breastfeeding is known to be the safest option. However, you don't have to give it up for the whole time you are breastfeeding. With some planning, you may be able to have an occasional glass. 

© Australian Breastfeeding Association April 2022