If you ask the internet if breastfeeding is good, you will soon learn that YOU MUST BREASTFEED because BREAST MILK = OPTIMAL FOOD FOR BABY. But if you look for evidence, you’ll discover two disturbing facts.

First, there's no consensus about why breastfeeding is good. I’ve seen experts suggest at least eight possible mechanisms:

Formula can’t fully reproduce the complex blend of fats, proteins and sugars in breast milk.
Formula lacks various bio-active things in breast milk, like antibodies, white blood cells, oligosaccharides, and epidermal growth factor.
If local water is unhealthy, then the mother's body acts as a kind of “filter”.
Breastfeeding may have psychological/social benefits, perhaps in part by releasing oxytocin in the mother.
Breastfeeding decreases fertility, meaning the baby may get more time before resources are redirected to a younger sibling.
Breastfeeding may help mothers manage various post-birth health issues?
Infants are often given formula [...]