Key takeaways
- Since 1900, the average American lifespan has grown by more than 30 years, and the CDC credits 25 of those years to public health measures such as clean water and safer food3.
- About 4,000 deaths from London’s 1952 coal smog were known at the time, the UK Met Office says, but a 2001 reassessment by Michelle Bell and Devra Davis estimated about 12,000 excess deaths over three months12.
- In 1960, about 48% of private-sector U.S. jobs required at least moderate physical activity; by 2008, about 20% did12.
- In a 2019 NIH trial, people offered ultra-processed meals ate about 500 more calories a day than when offered minimally processed meals15.
- Adults in three traditional societies studied in 2015 slept about 6 hours and 25 minutes a night on average, so electric light seems to have shifted our sleep timing more than it cut our hours1314.
On Friday, December 5, 1952, a fog settled over London and didn’t lift until the following Tuesday1. The weather was cold, and people were burning a great deal of coal to keep warm1. A high-pressure system put a lid of warm air over the city and trapped the smoke near the ground1.
According to Britain’s national weather service, the Met Office, each day of the fog poured about 1,000 tonnes of smoke particles into the air1. The smog also turned 370 tonnes of sulfur dioxide into 800 tonnes of sulfuric acid1. At times, people couldn’t see more than a few meters ahead1.
The Met Office says about 4,000 deaths were known at the time, and the true toll may have been much higher1. In 2001, researchers Michelle Bell and Devra Davis reexamined mortality records, hospital admissions and insurance claims. They estimated about 12,000 excess deaths from December 1952 through February 19532.
That same industrial century also brought safe city water, pasteurized milk and the home refrigerator45. In the United States, the average lifespan has grown by more than 30 years since 19003.
Natural health movements grew up partly as a reaction to industrial life. That reaction was often right. Sometimes it also rejected changes that saved millions of lives. This article sorts out which was which, and what the history suggests you keep, question or resist.
Clean water, safe milk and cold storage helped buy the extra years
In 1999, the Centers for Disease Control and Prevention (CDC) named ten great public health achievements of the 20th century3. It credited public health with 25 of the 30-plus years Americans gained3. The list includes vaccination, safer workplaces, safer and healthier foods, control of infectious diseases, and healthier mothers and babies3.
The numbers from 1900 are hard to read. About 100 of every 1,000 babies died before their first birthday, and in some U.S. cities the share reached 30%4. From 1915 to 1997, the infant death rate fell by more than 90%, to 7.2 per 1,000 births4.
The CDC credits sewage disposal, safe drinking water in cities and pasteurized milk, which Chicago introduced in 19084. Better incomes, nutrition and medical care helped too4.
Food got safer as well. Typhoid fever struck about 100 of every 100,000 Americans in 1900 and 1.7 per 100,000 by 19505. Home refrigerators with freezer compartments arrived in the 1920s and slowed the growth of bacteria in food5.
Industrial food also created its own scandals. Upton Sinclair’s 1906 novel The Jungle exposed filthy Chicago meatpacking plants, and public anger helped pass the Pure Food and Drug Act that year5.
Notice something about this list. Most of the biggest gains came from prevention: clean water, clean food, healthier homes and workplaces. That is a value natural-health readers already hold. Industrial tools, such as pumps, pipes, chlorine and cold storage, made prevention possible on a huge scale.
Industrial mills stripped the grain, and industry put some of it back
Bread changed in the late 1800s, when industrial roller mills transformed how grain was processed6. Refining strips away the bran, the fiber-rich outer layer, and the germ, the small nutrient-packed core6. Millers removed the germ partly because its oils shortened the flour’s shelf life6.
According to Harvard’s School of Public Health, refining wheat removes more than half of its B vitamins, about 90% of its vitamin E and nearly all of its fiber6. Flour can be enriched with some nutrients afterward, but plant compounds and other parts of the whole grain cannot be put back6.
The amount of flour wasn’t the big change. U.S. Department of Agriculture (USDA) data show that per-person wheat use generally fell from the late 1880s until about 19707. The bigger change was in the kind of flour.
Meanwhile, industrial food systems learned to fix some deficiency diseases. Pellagra, linked to poverty and poor diets, caused about 3 million cases and 100,000 deaths in the U.S. from 1906 to 19405. Better diets, economic recovery and the addition of niacin to flour nearly wiped it out by the end of the 1940s5.
Iodine was added to salt in 1924, and goiter rates in Michigan fell from 38.6% to 9.0% over 1922–19275. In 1921, about 75% of New York City infants had rickets; adding vitamin D to milk in the 1940s was key to controlling it5.
Sugar tells a different story, one about reversal. USDA figures show the supply of caloric sweeteners, a measure of what was available rather than what was eaten, was 151.3 pounds per person in 19998. By 2010, it had fallen to 131.9 pounds8. A trend that seemed built into modern life turned around.
Graham saw the factory loaf coming
Some Americans objected to industrial bread almost from the start. Sylvester Graham, born in Connecticut in 1794 and ordained as a Presbyterian minister in 1826, urged people to eat whole grains, fresh fruits and vegetables9.
He attacked the refined flour and chemical additives in factory-made white bread9. In his Treatise on Bread and Bread-Making, he called commercial bread “the most miserable trash that can be imagined”9. His followers, known as Grahamites, multiplied after the cholera epidemic of the 1830s9. In 1837, Boston grocers rioted against him at a hotel9.
Graham’s program went far beyond bread: no meat, no coffee or tea, and no alcohol9. Whatever you make of the rest, his core complaint about refined grain holds up well6. Our history of natural health movements, a companion article in this series, follows the line from Graham to John Harvey Kellogg’s sanitarium and beyond.
Coal smoke taught the world that air is a health issue
London’s smog didn’t stay a local tragedy. Britain passed Clean Air Acts in 1956 and 1968 that banned black smoke and moved city homes and factories to smokeless fuels1. Another London fog in 1962 killed about 750 people, but nothing on the scale of 1952 has happened since1.
The 2001 reassessment shows how extreme the episode was. Bell and Davis found that pollution levels during the fog were 5 to 19 times above modern standards, and death rates ran 50% to 300% higher than the year before2.
The United States moved in steps. The Air Pollution Control Act of 1955 was the first federal air pollution law, and it mostly funded research10. The Clean Air Act of 1963 created the first federal program to control air pollution10. The Clean Air Act of 1970 set national air quality standards, and the Environmental Protection Agency (EPA) was created that December to carry them out10.
Looking ahead, a 2011 EPA report projected that the 1990 amendments to the Clean Air Act would prevent more than 230,000 early deaths in 2020 alone11. Its central estimate put the benefits at more than 30 times the costs11. These are computer-model projections, not body counts, but they point in the same direction as London’s history.
Machines took the work out of work
Safer workplaces made the CDC’s list of great achievements3. But as machines and offices took over, work also stopped moving our bodies.
A 2011 study in the journal PLOS ONE, led by Timothy Church, tracked U.S. jobs over five decades. In 1960, about 48% of private-sector jobs required at least moderate physical activity12. By 2008, only about 20% did12.
The researchers estimated that daily calories burned at work fell by about 140 for men and 124 for women over that span12. A math model built on that drop predicted weight gain that closely matched national survey data12. The authors concluded that less active work explains a significant part of the rise in Americans’ average weight12.
A model is not proof. Food, cars, screens and sleep all changed in the same decades. Still, the lesson is concrete: for most of history, daily work was also daily exercise. Industrial life split them apart, and now most of us have to add movement back on purpose.
Electric light moved our body clocks, but the sleep story has a twist
Electric light let factories, homes and cities run after dark. Researchers have tested what that did to our internal clocks.
In a 2013 study led by Kenneth Wright of the University of Colorado Boulder, eight adults first wore light and activity monitors during a normal week13. Then they camped for a week in Colorado’s Eagles Nest Wilderness with only sunlight and campfires, and no flashlights or phones13.
Outdoors, they took in about four times the light intensity of their normal routine13. Under electric lighting at home, their biological night, measured by the sleep hormone melatonin, began about two hours later than it did after the camping week13. Night owls and early birds alike fell into step with the sun within a week13.
Here is the twist. A common belief holds that people slept far longer before electricity. A 2015 study led by UCLA sleep researcher Jerome Siegel tracked 94 adults in three traditional societies: the Hadza of Tanzania, the San of Namibia and the Tsimane of Bolivia14.
Their nights averaged about 6 hours and 25 minutes of sleep, and most got less than seven hours14. Sunset wasn’t bedtime: on average, they stayed up for 3 hours and 20 minutes after dark, then drifted off as the night air cooled14. Insomnia is rare enough that neither the San nor the Tsimane has a word for it14.
Both studies were small. Taken together, they suggest industrial light changed when we sleep and how well our bodies keep time, more clearly than it changed the total hours.
Ultra-processed food is the newest chapter of the same story
The factory kitchen has its own category in nutrition research. Researchers use a system called NOVA to sort foods by processing15. NOVA treats a food as ultra-processed when it contains ingredients found mainly in industrial food manufacturing, such as hydrogenated oils, high-fructose corn syrup, flavorings and emulsifiers15.
In 2019, National Institutes of Health (NIH) researcher Kevin Hall ran a rare tightly controlled test. Twenty healthy adults lived at the NIH Clinical Center for 28 days and spent two weeks on each of two diets, in random order15. The meals were matched for calories, sugar, fiber, fat and carbohydrates offered, and people could eat as much or as little as they liked15.
An ultra-processed breakfast might be a bagel with cream cheese and turkey bacon. The minimally processed breakfast was oatmeal with bananas, walnuts and skim milk15.
On the ultra-processed diet, people ate about 500 more calories a day and ate faster15. They gained about 2 pounds in two weeks, and they lost about as much on the minimally processed diet15. Hall called it “the first study to demonstrate causality” for ultra-processed food15.
The study had limits. It was small and short, and slight differences in protein may explain up to half of the extra calories15. Nobody yet knows exactly which feature of ultra-processed food drives the overeating15. Our companion guide on living naturally today covers the newer evidence and how much ultra-processed food Americans eat now.
Keep, question, resist: a way to sort modern changes
Industrial life is not one thing. It is hundreds of separate changes, and each deserves its own verdict. Here is one way to sort them, based on the history above.
| Change industrial life brought | Verdict | Why |
|---|---|---|
| Treated drinking water and sewers | Keep | Helped drive the steep fall in infant deaths and infection4 |
| Pasteurized milk and home refrigeration | Keep | Cut milkborne and foodborne disease45 |
| Iodized salt and vitamin D milk | Keep | Brought goiter and rickets under control5 |
| Clean-air laws | Keep | Helped end London’s deadly coal smogs; EPA model projections show large health gains111 |
| Enriched white flour | Question | Fixed some deficiencies, but fiber and plant compounds stay out56 |
| Bright light late at night | Question | Keep the light you need, but expect a later body clock13 |
| Workdays with no movement | Resist | Job-related activity fell sharply after 1960, so add movement back12 |
| Diets built mostly on ultra-processed food | Resist | Led to overeating in a controlled trial15 |
What the evidence supports
| Claim | Evidence level | What the research shows |
|---|---|---|
| Clean water, sewers and pasteurized milk cut deaths from infection | CDC lists them among the reasons infant death rates fell more than 90%4 | |
| Fortifying staple foods controlled deficiency diseases | Goiter, rickets and pellagra fell after iodine, vitamin D and niacin were added5 | |
| Heavy air pollution kills, and clean-air laws save lives | London’s 1952 death toll, plus EPA’s model projections of lives saved1211 | |
| Ultra-processed diets make people overeat | One small, tightly controlled inpatient trial15 | |
| Less active work explains much of U.S. weight gain | A modeling study that matched national data12 | |
| Electric light delays the body clock | A small camping study of eight adults13 | |
| People slept far longer before industrialization | Three traditional societies slept about 6 hours and 25 minutes on average14 | |
| Industrial life was simply bad for health | Lifespans grew by more than 30 years after 19003 |
Natural health traditions have long warned about refined food, dirty air and lives cut off from daylight and movement. History shows those warnings had real substance. It also shows that the biggest health wins of the industrial age were preventive tools, built at scale. The wise response is neither nostalgia nor blind trust in progress, but a careful sorting, one change at a time.
Questions readers ask
Was life healthier before industrialization?
For most people, no. In 1900, about 1 in 10 American babies died before age 14. But some things worth recovering were lost along the way, such as daily physical work and whole grains612.
If white flour is enriched, is it as good as whole wheat?
Not quite. Enrichment adds back some nutrients, but refining removes nearly all the fiber, and plant compounds from the bran and germ can’t be added back6.
Did people really sleep more before electric light?
The best evidence says probably not. Three traditional societies without electricity slept about 6 hours and 25 minutes a night on average14. Electric light seems to have mostly shifted the timing of sleep13.
What made the 1952 London smog so deadly?
Heavy coal burning in a cold snap, plus a layer of warm air that trapped the smoke over the city for five days1. Pollution rose to 5 to 19 times above modern standards2.
The bottom line
Industrialization was neither the fall from grace some natural-health writers describe nor the pure triumph its boosters claim. It gave Americans clean water, safe milk and cold storage, and it helped add more than three decades to their lives. It also gave them stripped-down flour, coal smog, sedentary jobs, late nights under bright lights and a food supply that makes overeating easy.
The lesson of that history is practical. Keep the preventive tools that work, question the conveniences that took something away, and resist the changes that undo your health. That is how the early reformers thought at their best, and it still works.
Related reading
About this article
This article was researched using CDC and EPA reports, USDA data, peer-reviewed studies and university sources, all listed below, and it was reviewed in October 2026. It is general education, not medical, legal or financial advice.
Sources
- UK Met Office. “The Great Smog of 1952.” Met Office, accessed 2026. weather.metoffice.gov.uk
- Bell ML, Davis DL. “Reassessment of the Lethal London Fog of 1952: Novel Indicators of Acute and Chronic Consequences of Acute Exposure to Air Pollution.” Environmental Health Perspectives, 2001 (abstract via Yale Bell Lab). bell-lab.yale.edu
- Centers for Disease Control and Prevention. “Ten Great Public Health Achievements — United States, 1900-1999.” MMWR, 1999. cdc.gov
- Centers for Disease Control and Prevention. “Achievements in Public Health, 1900-1999: Healthier Mothers and Babies.” MMWR, 1999. cdc.gov
- Centers for Disease Control and Prevention. “Achievements in Public Health, 1900-1999: Safer and Healthier Foods.” MMWR, 1999. cdc.gov
- Harvard T.H. Chan School of Public Health, The Nutrition Source. “Whole Grains.” Harvard, accessed 2026. nutritionsource.hsph.harvard.edu
- Economic Research Service, USDA. “Charts of Note: U.S. Per Capita Wheat Flour Use.” USDA ERS, 2013. ers.usda.gov
- Economic Research Service, USDA. “Charts of Note: U.S. Per Capita Caloric Sweetener Availability, 1999–2010.” USDA ERS, accessed 2026. ers.usda.gov
- Connecticut Humanities. “Sylvester Graham: Progressive Advocate for Healthy Living.” ConnecticutHistory.org, accessed 2026. connecticuthistory.org
- U.S. Environmental Protection Agency. “Evolution of the Clean Air Act.” EPA, accessed 2026. epa.gov
- U.S. Environmental Protection Agency. “Benefits and Costs of the Clean Air Act 1990-2020, the Second Prospective Study.” EPA, 2011. epa.gov
- Church TS, Thomas DM, Tudor-Locke C, et al. “Trends over 5 Decades in U.S. Occupation-Related Physical Activity and Their Associations with Obesity.” PLOS ONE, 2011. journals.plos.org
- University of Colorado Boulder. Release on Wright KP Jr, et al., “Entrainment of the Human Circadian Clock to the Natural Light-Dark Cycle,” Current Biology, 2013. CU Boulder Today, 2013. colorado.edu
- UCLA Health. “Our Ancestors Probably Didn’t Get 8 Hours a Night, Either” (on Yetish G, et al., Current Biology, 2015). UCLA Health, 2015. uclahealth.org
- National Institutes of Health. “NIH Study Finds Heavily Processed Foods Cause Overeating and Weight Gain” (on Hall KD, et al., Cell Metabolism, 2019). NIH, 2019. nih.gov