For as long as there have been babies, there have been debates over how to feed them.

Wet nursing, which began as early as 2000 B.C., was once a widely accepted option for mothers who could not or did not want to breast-feed, but it faced criticism during the Middle Ages and the Renaissance. The profession eventually declined with the introduction of the infant feeding bottle in the 19th century.

Today, and throughout the 20th century, the benefits of infant formula vs. breast-feeding have been examined from every angle. What was in vogue one decade became critiqued the next as cultural norms shifted, then shifted again.

Earlier this week, it was revealed that the Trump administration opposed an international resolution to encourage breast-feeding, stunning maternal health advocates and drawing swift criticism. But this isn’t the first time the United States has rejected such a measure.

Below, we chart America’s complicated history of infant feeding, starting with the spread of formula.