This site is intended for Healthcare Professionals only

8. Key ingredients of milks

Breastfeeding bookmark icon off

8. Key ingredients of milks

The following ingredients are present in both breast and infant formula milks to ensure babies get all the nutrients they need to thrive

Fats

Due to their fast growth rate, babies require three to four times more energy per kilogram of body weight than adults. Fat contains lots of calories and is a very concentrated source of energy, accounting for half the energy content of breast milk. This high energy density is important as babies have a limited stomach capacity. Fat also acts as the carrier for the fat-soluble vitamins A, D, E and K. Breast milk and most infant formula milks also contain essential fatty acids and long-chain polyunsaturated fatty acids (LCPs), including arachidonic acid (AA) and docasahexaenoic acid (DHA).

Carbohydrates

The main carbohydrate is lactose, a natural milk sugar that provides 40 per cent of the energy content of breast milk. Breast and infant formula milks also contain oligosaccharides, a type of carbohydrate consisting of linked sugar units. Also included are fructo- and galacto-oligosaccharides.

Proteins

Protein is required for the growth and maintenance of muscles and bones. Casein and whey are the two main proteins, which occur in breast milk in a ratio of 40:60. 

  • Whey protein forms an easily-digestible soft curd. In breast milk, whey protein also contains other important proteins: lactoferrin, lysozyme, alpha-lactalbumin, and immunoglobulins   
  • Casein protein has coagulating properties, so forms a firmer curd that may take longer to digest.

Vitamins

  • Vitamin A: contributes to normal immune system function, maintenance of normal vision and skin, and helps the body metabolise iron
  • Vitamin D: needed for calcium absorption, it contributes to normal function of the immune system and helps maintain normal teeth, muscle function and bones
  • Vitamin E: helps to protect cells from oxidative stress
  • Vitamin K: helps maintain normal bones and blood clotting
  • Vitamin C: contributes to normal immune and nervous system function. Increases iron absorption 
  • B vitamins: important for energy metabolism.

Casein and whey are the two main proteins, which occur in breast milk in a ratio of 40:60

Minerals

  • Calcium: needed for the maintenance of normal bones and teeth, and contributes to normal blood clotting and muscle function
  • Phosphorus: contributes to the maintenance of normal bones and teeth
  • Zinc: contributes to normal cognitive function, the metabolism of fatty acids and vitamin A, and the maintenance of normal bones, vision and immunity
  • Selenium: protects cells from oxidative damage
  • Iodine: important for growth and normal cognitive function
  • Iron: contributes to normal cognitive function. The iron content of breast milk is low as babies are generally able to rely on their own stores until four to six months of age. At this age, babies need a dietary source of iron. Iron is more efficiently absorbed from breast milk than infant formula milk, which is why infant formula milk contains higher levels.

Probiotics and prebiotics

Prebiotics are non-digestible ingredients that stimulate the growth of “friendly” bacteria – or probiotics – in the gut. These are live bacteria and yeast that can change the gut’s bacterial balance. Probiotics help to push food through the gut and keep the digestive tract healthy. Some clinical trials suggest that probiotics may also have a role in supporting gastrointestinal health in healthy children, potentially helping to treat things like irritable bowel syndrome, inflammatory bowel disease, diarrhoea, colic and eczema.

Prebiotic oligosaccharides are the third most prevalent component of breast milk but are virtually absent in cows’ milk, which is why they are often added to infant formula to mimic the benefits. Research shows that differences in the bacterial balance in the gut and incidence of infection exist between breast-fed and formula-fed infants, with the former thought to have improved protection. Whether this formula milk supplementation is as beneficial as natural prebiotics in breast milk is still being debated.

Copy Link copy link button

Breastfeeding

Share: