During the last trimester, babies acquire reserves of energy and nutrients. After birth, nutrients are provided by milk with healthy babies doubling their birth weight by the time they are 6 months old.
The miracle of breast milk
The composition of breast milk changes to suit the needs of baby – changing during feeds, the time of day and during lactation. Not only is it the best food for babies, containing all the energy and nutrients that they need but it also includes elements that provide protection from viral and bacterial infections as well as substances that may aid growth and development.
Because of the fast rate of growth, babies need a much greater amount of energy compared to body weight than adults. Fats supply half of the energy content of breast milk and also provide prostaglandins and fat soluble vitamins A, D, E, & K. Breast milk also provides docosahexaenoic and arachidonic acid and omega 3 and omega 6 fatty acids needed for brain and neural development.
At 40%, this supplies most of the rest of the energy provided by breast milk. This is mainly lactose but also includes monosaccharides and oligosaccharides – the latter helping develop probiotic intestinal flora like bifidobacteria and possibly defending against viruses and bacteria.
Babies need protein for developing and maintaining tissue and for making enzymes. There are two types.
1. Casein. It makes up 40% of the protein in breast milk and makes a fine curd in the stomach that takes longer to digest than whey.
2. Whey. This makes up the other 60% and contains lactoferrin and lysozyme, both of which inhibit bacteria. It also includes immunoglobulins (antibodies) and alpha-lactalbumin to help balance essential amino acids.
VITAMINS & MINERALS
Breast milk from a well-nourished mother should provide vitamins A, B, C and E. Vitamin A helps with growth, healthy skin & eyes and the immune system. B helps metabolise energy. Vitamin C helps absorb iron and to form collagen for making skin, scar tissue, blood vessels, tendons and ligaments. Vitamin E is important in metabolism.
Breast milk does not provide adequate amounts of vitamin D or K. Vitamin D is needed for calcium absorption. There is a risk of poor bone growth and rickets without it. It can be synthesized by exposure to sunlight but this is not appropriate for infants. Pregnant and breastfeeding women are recommended to take 10 mg supplements of vitamin D daily. Vitamin K is important for blood clotting and is synthesized in the gut. Intramuscular or oral supplements can be provided by the midwife during baby’s first few weeks.
Infants require calcium and phosphorus for bone growth with calcium also involved in blood clotting, nerve transmission and muscle contraction. Zinc is essential for growth and the immune function and iron has many uses including helping transport oxygen. By 4-6 months, baby’s store of iron, provided in the womb by mum, is depleting and needs to be re-supplied through diet.
Ronesca recognizes World Health Organisation recommendations and encourages mothers to breastfeed for the first 6 months (26 weeks) of life. There are many occasions, however, when breastfeeding is not possible and for babies under the age of 1 year, infant formula is the only alternative.
Based on cow’s milk, many infant formulas have been developed to mimic the content of breast milk. Some infant formulas like Ronalac have gone further in order to mimic the biological effects and benefits of breast milk. Their enriched formulas will typically have revised proportions of prebiotcs, probiotics and long-chain polyunsaturated fatty acids.