Why our babies are more like kangaroos than cows – and what that means for your breastfeeding experience
Mammals and Their Milk
All mammals produce milk to feed their young. This is where the word “mammal” comes from. Not all of that milk is the same though and mothering styles vary along with the different types of milk. You can actually connect different mothering styles to the different types of milk animals produce.
The protein and fat found in milk is what keeps babies full and satisfied for longer periods of time. The same goes for grown-ups which is why diets tend to emphasize protein for snacks to keep you full longer. In the mammal world human milk is a bit like a timbit (except that it is much more nutritious). If you were to try and keep full for more than 2-3 hours on some timbits it would be pretty tough. They contain lots of sugar and some fat but little in the way of protein. Some other mammals though, have milk that’s more like a massive protein shake with a bunch of fat thrown in for good measure.
Human Milk – What’s it Made of?
Human milk contains 0.8-1% protein – the lowest of all mammals. Human milk is also the sweetest of all the milks in the animal kingdom. This is because our brains run on sugar. Big brain = big amount of sugar in our milk.
Human milk contains only 3-5% fat. Human milk starts out more watery and sweet at the beginning of the feed and creamier with more fat near the end. These different phases of milk during a feed are called foremilk and hindmilk. Foremilk at the beginning helps to satisfy a baby’s thirst and need for some quick energy before finishing off with the creamier hindmilk that may keep them full for a while.
So human milk contains a tiny bit of protein, little bit of fat and lots of sugar. Unfortunately for us this means our milk has the staying power of that timbit – our babies need to feed almost around the clock when they start out to stay full and satisfied.
Different Mammals – Different Milks
1. Cache mammals
Deer, Seal, Rabbits – Born mature
Milk Content: Highest fat and protein content - Hooded seals milk contains approximately 60% fat!
Seals and other cache mammals leave their young for up to 12 hours at a time
2. Follow mammals
Giraffes, Cows – Less mature at birth
Milk Content: Lower fat and protein content
Young follow their mothers to feed at shorter intervals
3. Nest mammals
Dogs, Cats – Even less mature at birth
Milk Content: Even lower fat and protein content
Mothers return to litter to feed young often
4. Carry mammals
Kangaroos, primates, humans – Least mature at birth - Human babies are born extremely immature compared to most other mammals
Milk Content: Least amount of fat and protein
Mothers maintain continuous body contact with young and feed around the clock
What does this all mean if you're breastfeeding a newborn?
All of this means that in those first few draining newborn months you can expect that your baby will want to be held all of the time and possibly also to breastfeed every 1-2 hours (or sometimes it may seem even more frequent!). You may luck out and have a baby that settles on their own early on, and feeds at 3 hour intervals – I’ve known this to happen. But if you don’t, and you have a newborn that needs to be held and fed constantly hang tight, the kangaroos and primates are right there with you ;)
References
Mannel, R., Martens, P.J., & Walker, M. (2013). Core Curriculum for Lactation
Consultant Practice (3rd ed.). Burlington, MA: Jones & Bartlett Learning.
Wilson-Clay, B., & Hoover, K. (2015). The Breastfeeding Atlas (5th ed.).