We humans have evolved to drink our mother’s milk until anywhere between the ages of around 2 and 7+ years old. Some babies stop earlier, some children carry on for longer. This is known as natural term breastfeeding, or natural term weaning. It’s thought that the eruption of the permanent set of teeth influences this timescale.
Many cultures around the world breastfeed until natural term, including many women in the Western world. This age range is only surprising in cultures that interrupt breastfeeding, often without realising it or knowing which norms are biological and which are cultural.
The concentration of fats and proteins increase as the baby grows into a toddler, along with increased levels of antibacterial and antiviral components such as lysozyme, which is an anti-inflammatory and destroys bacteria. Lysozyme increases in concentration from about 6 months old, and keeps increasing after the first year.
The concentration of Lactoferrin also increases over time. Lactoferrin inhibits the growth of some cancerous cells. It also helps our babies to absorb their own iron stores, whilst binding to the iron in our baby’s body which prevents it from being available to harmful microorganisms that need iron to survive. Lactoferrin also kills the bacteria strep mutans, which causes tooth decay and cavities.
Our body’s immune system takes around 6 years to become fully mature, so the support of the protective factors in human milk could play a part in the timescale of natural term weaning.
It is also associated with a reduced risk of disease for the mother, including breast cancer.
We acknowledge that many mothers find it difficult to establish breastfeeding in the first place, that breastfeeding is a multi-layered investment on the part of a mother and that natural term feeding might not feel like - or be - a possibility for many.
We also acknowledge that lack of information about our biology contributes to the lack of support for mothers when they want to establish - or continue - breastfeeding, but cannot find the help they need from people who understand why it matters so much.
Let's continue to turn that around.