Long before lactation consultants talked about stress and milk supply, a nursing mother in the 1940s agreed to an experiment that sounds almost cruel today. While she fed her baby, researchers dipped her feet in ice water, pulled on her big toe until it hurt, and fired difficult math problems at her, delivering a shock for each wrong answer.
Each time, the baby got less milk. The study, published in 1948 by Dr. Michael Newton and Niles Newton, became an early experimental look at how distress can interfere with the human milk letdown reflex, and its lesson still shapes how clinicians think about breastfeeding support nearly 80 years later.
