What Exactly Is In Breastmilk?

The composition of breastmilk depends on a number of factors, and breastmilk is constantly changing - even throughout a single feed where the first (or fore) milk is thirst-quenching, and the later (or hind) milk is rich, creamy and full of good fats. It will adapt to meet your baby’s individual nutrition and fluid requirements, so the composition can vary depending on the time of day and between mothers.  

What are the nutrients in breastmilk?

Breastmilk contains all the nutrients your baby needs for proper growth and development, including:

• Water
• Proteins
• Essential fatty acids and long-chain polyunsaturated fatty acids
• Carbohydrates – the principal carbohydrate being lactose
• Minerals, vitamins, and trace elements; including sodium, calcium, phosphorus, iron, vitamin A, vitamin C and vitamin D

Breast milk also contains important non-nutritional components, such as antimicrobial factors, digestive enzymes, hormones and growth factors that can protect against infections and immune-related diseases, and help build the immune system.  

The different stages of lactation

There are three stages of lactation, and the nutrients found in breastmilk will change from stage to stage. Here’s how:

• Colostrum - Colostrum is the secretion produced during the first few days (1-7 days) after birth and differs from both transitional and mature milk. It contains a higher amount of protein, less fat and a number of immunising factors for your newborn
• Transitional milk - produced from approximately day 8 – 20, this is the milk produced during the transition from colostrum to mature milk, where lactation is established and production of milk begins in the breast tissue. It shares some of the characteristics of colostrum, but is a period of ‘ramped up’ milk production to support the nutritional and developmental needs of your baby– this is the time your milk will ‘come in’ and you may experience engorgement as the volume rapidly increases
• Mature milk - produced from 20 days after birth, onwards, this milk can vary in and between individuals, and the energy (or calories) can vary between 270 and 315 kJ per 100mL. This is largely due to the variation in the fat content, as the fat of the milk received by your baby increases as the feed progresses. Mature milk continues to provide immune factors and other important non-nutritional components

The food factor

A 'perfect' diet is not required for breastfeeding- however, for mothers eating a normal Australian diet, sufficient iodine, iron and calcium intake may still be a concern. Talk to your healthcare practitioner to find out if you have enough of these in your diet, as they may recommend supplementation.

A healthy diet, rich in whole grains, legumes, fruit and vegetables, lean protein, low fat dairy and plenty of water will help you keep your energy up while you breastfeed – while your body will continue to make breastmilk, it’s important that you  pay enough attention to consuming a quality diet to maintain your own wellbeing.  And if you are concerned please speak to your healthcare professional.

Blackmores supports the benefits of breastfeeding as the best source of nutrition for babies. However, we also recognise that not all mums are able to breastfeed, and the reasons women are not able to breastfeed are for each mum to discuss with her health care professional.