The result of both inadequate support for new mothers and poor medical advice was that more and more mothers bottle-fed their babies cow’s milk. Young children drank lots of milk, too. Medical authorities like the pediatrician Luther Emmett Holt, whose 1894 The Care and Feeding of Children would become the most popular parenting manual of the early 20th century, advised parents to feed their toddlers milk at every meal.
But for kids at the turn of the century, milk came with dire risks. Amid the unbridled capitalism of the Gilded Age, the milk supply was a nightmare of corruption and contamination. On the farm, poor sanitation enabled cows and dairy workers to introduce tuberculosis, typhoid, and other pathogens into milk. Farmers or middlemen also frequently adulterated milk, watering it down to stretch supplies—with impure water likely to introduce further pathogens—or adding toxic substances, like formaldehyde or chalk, meant to conceal spoilage or make milk appear whiter. The milk was then shipped in open, unrefrigerated containers no matter the weather, vulnerable to even more contamination and spoilage.
This poisoned milk threatened America’s most vulnerable consumers: young children. Infant mortality skyrocketed in the second half of the 19th century, up to 20% nationally and closer to 30% in urban centers. Tens of thousands of babies died every year of gastroenteritis known as “the summer complaint,” an epidemic of diarrhea that worsened in the warmer months. Gastrointestinal infections were the third leading cause of death across all ages, but particularly impacted small children’s fragile immune systems.
Parents, many mourning dead children, pushed for lawmakers to clean up the milk supply. They joined a movement of Americans calling for government regulation of the food industry. Progressive Era reformers chronicled the lax food safety and labor conditions that put Americans at risk. In 1902, a Department of Agriculture chemist named Harvey Wiley launched a brilliant but dangerous public relations campaign dubbed “The Poison Squad” dosing human test subjects with food additives like formaldehyde and chronicling their alarming effects on the body. In his famous 1905 novel The Jungle, the journalist Upton Sinclair exposed the horrors of meatpacking plants and the threat they posed to Americans.
This activism prodded state and federal authorities to enact a flurry of public health legislation. In 1906, Congress passed the Pure Food and Drug Act, leading to the creation of the FDA. In 1910, New York State mandated the pasteurization of all milk sold for human consumption. As an extra layer of oversight, public health authorities began testing cows for diseases like tuberculosis, to ensure that milk remained safe for American consumers.