One of the most dramatic effects of industrialization was massive urbanization, a rapid shift of people from rural farmland into crowded cities. In 1600, fewer than 8 percent of people in England and Wales lived in towns of 5,000 or more. By 1851, over half the population lived in settlements of 2,500 or more, and that figure peaked at roughly 80 percent by the 1890s. This single shift, millions of people concentrating into dense urban areas to work in factories, triggered a chain of consequences that reshaped public health, the environment, working life, and human bodies themselves.
Cities Grew Faster Than They Could Handle
Urbanization during the Industrial Revolution wasn’t a gradual drift. It accelerated sharply in the first half of the 1800s, as factories in cities like Manchester, Birmingham, and London drew workers away from agricultural life. Cities that had been modest market towns doubled or tripled in population within a generation. The infrastructure to support these people, clean water, sewage systems, housing, simply did not exist yet.
The result was extreme overcrowding. Families packed into poorly ventilated tenements. Streets served as open sewers. Drinking water was drawn from rivers or shallow wells positioned dangerously close to cesspools, often so close that the water had a noticeable odor and taste. These conditions turned industrial cities into breeding grounds for infectious disease.
Disease Spread Through Crowded Cities
Cholera became one of the signature killers of the industrial age. The disease thrived in exactly the conditions industrialization created: dense populations sharing contaminated water supplies with no sanitation systems to speak of. During the 1849 to 1851 outbreak in the United States, St. Louis lost 4,557 people, Cincinnati lost 5,969, and Detroit lost 700. In each outbreak, deaths typically reached 5 to 10 percent of the local population.
Smaller towns fared even worse in proportion. Napoleon, Indiana, a stagecoach hub of about 250 people, lost 35 residents to cholera in 1849, roughly 14 percent of its population in a single season. Salem, Indiana, an inland village of just a few hundred, recorded 113 deaths in July and August of 1833 alone. Transportation networks that industrialization expanded, stagecoach routes and later railroads, carried the disease between communities that might otherwise have been isolated from outbreaks.
At the time, most people blamed cholera on bad air, filthy living conditions, or the moral failings of the poor. Local merchants sometimes tried to suppress news of outbreaks because cholera was bad for business. The actual cause, bacteria in contaminated water, wouldn’t be widely understood until decades later, and meaningful sanitation reform followed even more slowly.
Air Quality Deteriorated for Centuries
Coal powered the Industrial Revolution, and coal smoke choked the cities where it burned. In London, sulfur dioxide levels reached nearly 200 micrograms per cubic meter and stayed at that plateau from roughly 1690 to 1880. Particulate matter, the tiny soot particles that penetrate deep into the lungs, peaked at the end of the 19th century. For people living and working in industrial cities, breathing this air every day contributed to chronic respiratory illness on a scale that preindustrial populations had never experienced.
The atmospheric impact extended far beyond any single city. Before industrialization began in the mid-1700s, carbon dioxide in the atmosphere measured about 280 parts per million. By 2024, the global average hit 422.8 parts per million, a new record and a 50 percent increase over preindustrial levels. The coal, oil, and gas combustion that industrialization set in motion is the primary driver of that rise, making climate change one of the longest-lasting consequences of the industrial era.
Workers Got Shorter, Not Healthier
One of the more counterintuitive findings about industrialization is that it initially made people physically smaller. Average height is a reliable indicator of childhood nutrition and health, and multiple studies using historical records have found that average heights declined during the first half of the 1800s. Children born in the 1830s showed clear evidence of stunting compared to modern growth standards.
This happened because the conditions of industrial life, overcrowded housing, polluted air, contaminated water, long working hours starting in childhood, outweighed whatever gains in food supply or wages industrialization might have produced. The nutritional deficit hit the working poor hardest. Comparisons between the heights of military academy recruits (a stand-in for the wealthy) and boys from charitable institutions (a stand-in for the very poor) reveal significant height gaps between social classes. Studies from Switzerland found the same pattern: higher social groups had a measurable height advantage over lower ones. Industrialization made the economy larger, but for the first several decades, it made ordinary people’s bodies smaller.
The Workday Stretched to Its Limits
Factory work restructured time itself. Before industrialization, agricultural labor was grueling but followed seasonal rhythms, with longer days at harvest and shorter ones in winter. Factory work was relentless year-round. By 1880, the average workday in American manufacturing was almost exactly 10 hours, and that was after decades of gradual reduction from even longer shifts earlier in the century. Workers in the 1830s and 1840s commonly worked 12 to 14 hours a day, six days a week.
Analysis of 1880 census data from manufacturing firms reveals some interesting patterns within this system. Higher-paid workers tended to trade some potential earnings for more leisure time, suggesting that when people had any bargaining power at all, they chose shorter hours. Hours and days of employment moved together, meaning that when daily shifts were long, the number of working days per year was also high. There was little in the way of tradeoff between a brutal daily schedule and more days off. The push for labor regulations, including the eight-hour workday that wouldn’t become standard until the early 20th century, was a direct response to the exhausting pace that industrialization demanded.
Inequality Widened Between Classes
Industrialization generated enormous new wealth, but it did not distribute that wealth evenly. Factory owners and investors accumulated capital at rates that were previously impossible, while the workers who operated the machinery often lived in poverty. The height data tells this story in physical terms: the bodies of the rich and the poor diverged measurably during the industrial period, reflecting vastly different access to nutrition, clean living conditions, and rest.
This inequality wasn’t just about income. It was about exposure to risk. Wealthier residents of industrial cities could afford to live in neighborhoods with better air and cleaner water. They could feed their children adequately. Workers could not. The same economic engine that created unprecedented productivity also created a class of people whose living standards, by several biological measures, were worse than those of their preindustrial ancestors. It took decades of labor organizing, public health reform, and government regulation before the benefits of industrialization began to reach the broader population.