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Three Cheers for Refrigeration—and Four, Once Everyone Has It

Blog Post | Health & Medical Care

Three Cheers for Refrigeration—and Four, Once Everyone Has It

Refrigerators have revolutionized health and wellbeing for those with access to them, but their affordability is under fire.

Summary: Refrigeration has revolutionized public health and improved the quality of life worldwide, but its future is under threat. The remarkable benefits it brings, such as reducing foodborne illnesses and improving the quality of food, are being undermined by misguided climate change policies that increase costs. This article explains why it is crucial to prioritize the accessibility and affordability of refrigeration and reliable electricity, as they are such powerful keys to human progress.

It is difficult to overstate the benefits of refrigeration. Even more than its technological sibling air conditioning, refrigeration has dramatically improved public health and the quality of life wherever it has become widespread. And unlike air conditioning, the utility of which is questioned in some intellectual circles, refrigeration has few if any critics. Nonetheless, in an age when climate change has become the near obsession of most international policymakers—and given that refrigeration does require a considerable amount of (often) fossil-fuel fired electricity—it is worth highlighting the importance of avoiding measures that threaten its continued spread throughout the world.

The Rise of Refrigeration and Fall of Foodborne Illness

In 2013–2014, salmonella-contaminated chicken from Foster Farms in California caused a known 634 illnesses across 29 states. This major outbreak and recall received substantial press coverage at the time, as have similar ones that have happened. But before refrigeration, such incidents would not have been treated as news; they were an everyday reality.

Along with air conditioning, the United States was the first nation to have a refrigerator in most residences, as well as an extensive cold chain among food producers and wholesalers and retailers upstream of the consumer. Therefore, America provides the longest test case of the public health benefits from having a food supply that can be kept cold as needed. Those benefits are impressive.

It is over the last century that American households went from zero to nearly 100 percent in refrigerator use. Indeed, market penetration was already above 80 percent by the 1940s. Thanks to a fridge in every kitchen, and along with other major advances like pasteurization, food-related illness and mortality have seen a precipitous decline.

Even health outcomes not obviously connected to refrigeration have benefited from it. For example, there is considerable evidence that cancers of the stomach became considerably less common in the United States thanks to refrigerators.

Beyond reducing foodborne illness, refrigeration has also improved the quality of the food supply. This is particularly true for protein sources like dairy, meat, and fish that are quickly perishable without it. It has also enabled wider and year-round availability of fresh fruits and vegetables. These fresh (and also fresh frozen, as sizeable freezer sections have become a standard feature in refrigerators) foods have largely replaced heavily salted or smoked or pickled foods, and thus improved diets.

Lower income households have benefited the most from refrigeration. Not only has the cost of a high-quality diet come down, but the once-considerable expense of food spoilage has been reduced. This is particularly important for those who live in hotter regions.

Given all the health benefits of a safer and better food supply attributable to refrigeration, there is little doubt it has contributed to the considerably longer life expectancies in the United States over the past century. Granted, improved health care has been the main driver of these improvements, including vaccines against many once-common diseases. But even with that, refrigeration has played a vital role in the manufacture, transport, and storage of those vaccines as well as in many other medical applications.

Progress and Challenges toward Global Availability of Refrigeration

Refrigerators started as a luxury good a century ago, but prices have substantially declined since (although it should be noted that the recently growing regulatory burden on appliances in the United States and Europe may undercut this trend). Today, very few kitchens in the developed world are without a refrigerator, and market penetration in the developing world has been robust, particularly over the last three decades.

At this point, equipment cost is a barrier for only the world’s very poorest households. However, United Nations efforts favoring “climate-friendly” refrigerators represent a worrisome trend threatening affordability. For example, many existing refrigerators use refrigerants called hydrofluorocarbons (HFCs) that are considered to have a high per-molecule global warming potential, though their overall contribution to anthropogenic warming is only 3 percent. These refrigerants are now subject to restrictions pursuant to the Kigali Amendment, a United Nations treaty.

Although the Kigali Amendment is more lenient toward developing nations than developed ones, it will nonetheless harm the developing world’s refrigerator buyers in two ways. First, the treaty and implementing provisions will serve to disrupt with the supply of second-hand refrigerators from first-world nations, which are often the lowest cost option in developing nations. In fact, the trade in such refrigerators is now perceived by many in the international community as an environmental threat that needs to be eradicated. Second, the Kigali Amendment will eventually impose restrictions on the types of new systems allowed to be produced in developing nations.

These measures are fairly new and are just beginning to be implemented, so the impact on equipment costs is not yet known. But they will likely raise, at least to some extent, the purchase price of a refrigerator. It does not take much of an increase to have a deleterious impact on market penetration among the world’s poorest households.

Access to Reliable Electricity

While refrigerator affordability is an ongoing concern, the greater obstacle is access to reliable electricity.

The slow march to a completely electrified world is 90 percent complete. We have finally reached the point where most of the developing world has joined the developed world in being electrified, but about 750 million people still don’t have it. Worse, by adding in those lacking access to reliable electricity, the number jumps to 3.5 billion, according to one estimate. In Africa, less than half the population enjoys access to reliable electricity.

An unreliable electricity supply can significantly undercut the advantages of refrigeration, as anyone who has had to clean out the fridge after an extended blackout can attest. More progress on both the availability and reliability of electricity is still needed if the benefits of refrigeration are to become universal.

Once again, the climate change agenda is becoming a growing impediment. Progress on electrification is jeopardized by the United Nations’ Paris Agreement and other measures that target affordable and reliable—but carbon-emitting—coal and natural gas in favor of intermittent and unreliable wind and solar. Doing so threatens to both slow progress in expanding electrification for those who don’t yet have it and to improve reliability for those who do.

Even in the first world where refrigeration has long been nearly universal, there are risks from mandates and subsidies for an increasingly renewables-heavy electricity mix chosen for climate considerations at the expense of reliability. If unchecked, this trend could lead to more frequent blackouts and, thus, backsliding on the refrigeration benefits people take for granted. This is especially so for the summer months when refrigeration is most vital.


Today, a large and growing number of the world’s households, both rich and poor, are able to buy a refrigerator, plug it in, and enjoy the benefits of its uninterrupted operation. This has been an indisputably significant boon to the safety and quality of the food supply and thus to public health. However, ill-advised climate change policy measures are emerging as a real threat to refrigeration’s continued spread. Prioritization of a climate agenda that raises the cost of a refrigerator is likely to do considerably more harm than good and deter the spread of affordable and reliable electricity throughout the world. Refrigeration has been a growing success story for humanity over the past century, but continued progress is now at risk.

Blog Post | Human Development

1,000 Bits of Good News You May Have Missed in 2023

A necessary balance to the torrent of negativity.

Reading the news can leave you depressed and misinformed. It’s partisan, shallow, and, above all, hopelessly negative. As Steven Pinker from Harvard University quipped, “The news is a nonrandom sample of the worst events happening on the planet on a given day.”

So, why does Human Progress feature so many news items? And why did I compile them in this giant list? Here are a few reasons:

  • Negative headlines get more clicks. Promoting positive stories provides a necessary balance to the torrent of negativity.
  • Statistics are vital to a proper understanding of the world, but many find anecdotes more compelling.
  • Many people acknowledge humanity’s progress compared to the past but remain unreasonably pessimistic about the present—not to mention the future. Positive news can help improve their state of mind.
  • We have agency to make the world better. It is appropriate to recognize and be grateful for those who do.

Below is a nonrandom sample (n = ~1000) of positive news we collected this year, separated by topic area. Please scroll, skim, and click. Or—to be even more enlightened—read this blog post and then look through our collection of long-term trends and datasets.



Farming robots and drones

Food abundance

Genetic modification

Indoor farming

Lab-grown produce


Other innovations

Conservation and Biodiversity

Big cats




Other comebacks



Rivers and lakes

Surveillance and discovery

Rewilding and conservation


Culture and tolerance

Gender equality

General wellbeing


Treatment of animals

Energy and natural Resources



Fossil fuels

Other energy

Recycling and resource efficiency

Resource abundance

Environment and pollution

Climate change

Disaster resilience

Air pollution

Water pollution

Growth and development


Economic growth

Housing and urbanization

Labor and employment



Disability and assistive technology

Dementia and Alzheimer’s


Heart disease and stroke

Other non-communicable diseases



Other communicable diseases

Maternal care

Fertility and birth control

Mental health and addiction

Weight and nutrition

Longevity and mortality 

Surgery and emergency medicine

Measurement and imaging

Health systems

Other innovations



    Artificial intelligence



    Construction and manufacturing


    Robotics and automation

    Autonomous vehicles


    Other innovations


    AI in science


    Chemistry and materials






      Bloomberg | Infrastructure & Transportation

      An Underground Lunch Delivery Train Comes to the Atlanta Suburbs

      “Underground tubes are already the transportation method of choice for essentials like water, sewage, and Wi-Fi. This week, one Georgia city will start sending sandwiches through the pipes, too.

      Peachtree Corners, northeast of Atlanta, is the first test case for an underground last-mile delivery mode, developed by the logistics startup Pipedream Labs. Founded in 2021, the company seeks to solve the problems that plague the terrestrial delivery space: the emissions and congestion from vehicle traffic, the jockeying for curb space, and the costs. About 40% of supply chain logistics expenses are associated with last-mile trips.”

      From Bloomberg.

      Blog Post | Food Prices

      Eight Centuries of Increasing Food Abundance in England: Dairy (Part 2)

      The work required for an average English worker to afford a gallon of milk has fallen from 13 hours to 14 minutes.

      Human progress is often incremental, but many positive trends have become clearly visible over time. One of these trends is the growing abundance of food. This series of articles looks at the affordability of food relative to wages in England between the 13th century and the present.

      For this series, the average nominal hourly wage since 1260 came from the Bank of England’s Millennium of Macroeconomic Data. The UK Office of National Statistics collected nominal prices of milk, cheese, and butter since 1914. The price data for before 1914 is from professor Gregory Clark’s “The Price History of English Agriculture, 1209–1914.”

      Figure 1: A continuous series of dairy product abundance

      An hour’s work buys a lot more than it used to. For much of English history, the purchasing power of the average nominal wage remained relatively constant. There were some fluctuations, such as cheese becoming slightly more abundant in the 1400s. However, the purchasing power of nominal wages increased rapidly during the 20th century.

      Figure 2: A continuous series of dairy product time prices

      As we can see, at its peak, an English worker worked over 13 hours to afford a gallon of milk. That fell to just 14 minutes in 2022 (i.e., less than 2 percent of the previous time price). Next time you hear someone complaining about increasing food prices, think about just how affordable they are compared to the past. Food is much more affordable in terms of the one commodity that is truly scarce: our time.

      Blog Post | Wellbeing

      Is This the Best Time to Be Alive?

      Overwhelming evidence shows that we are richer, healthier, better fed, better educated, and even more humane than ever before.

      Imagine, if you will, the following scenario. It is 1723, and you are invited to dinner in a bucolic New England countryside, unspoiled by the ravages of the Industrial Revolution. There, you encounter a family of English settlers who left the Old World to start a new life in North America. The father, muscles bulging after a vigorous day of work on the farm, sits at the head of the table, reading from the Bible. His beautiful wife, dressed in rustic finery, is putting finishing touches on a pot of hearty stew. The son, a strapping lad of 17, has just returned from an invigorating horse ride, while the daughter, aged 12, is playing with her dolls. Aside from the antiquated gender roles, what’s there not to like?

      As an idealized depiction of pre-industrial life, the setting is easily recognizable to anyone familiar with Romantic writing or films such as Gone with the Wind or the Lord of the Rings trilogy. As a description of reality, however, it is rubbish; balderdash; nonsense and humbug. More likely than not, the father is in agonizing and chronic pain from decades of hard labor. His wife’s lungs, destroyed by years of indoor pollution, make her cough blood. Soon, she will be dead. The daughter, the family being too poor to afford a dowry, will spend her life as a spinster, shunned by her peers. And the son, having recently visited a prostitute, is suffering from a mysterious ailment that will make him blind in five years and kill him before he is 30.

      For most of human history, life was very difficult for most people. They lacked basic medicines and died relatively young. They had no painkillers, and people with ailments spent much of their lives in agonizing pain. Entire families lived in bug-infested dwellings that offered neither comfort nor privacy. They worked in the fields from sunrise to sunset, yet hunger and famines were common. Transportation was primitive, and most people never traveled beyond their native villages or nearest towns. Ignorance and illiteracy were rife. The “good old days” were, by and large, very bad for the great majority of humankind. Since then, humanity has made enormous progress—especially over the course of the last two centuries.

      How much progress?

      Life expectancy before the modern era, which is to say, the last 200 years or so, was between ages 25 and 30. Today, the global average is 73 years old. It is 78 in the United States and 85 in Hong Kong.

      In the mid-18th century, 40 percent of children died before their 15th birthday in Sweden and 50 percent in Bavaria. That was not unusual. The average child mortality among hunter-gatherers was 49 percent. Today, global child mortality is 4 percent. It is 0.3 percent in the Nordic nations and Japan.

      Most of the people who survived into adulthood lived on the equivalent of $2 per day—a permanent state of penury that lasted from the start of the agricultural revolution 10,000 years ago until the 1800s. Today, the global average is $35—adjusted for inflation. Put differently, the average inhabitant of the world is 18 times better off.

      With rising incomes came a massive reduction in absolute poverty, which fell from 90 percent in the early 19th century to 40 percent in 1980 to less than 10 percent today. As scholars from the Brookings Institution put it, “Poverty reduction of this magnitude is unparalleled in history.”

      Along with absolute poverty came hunger. Famines were once common, and the average food consumption in France did not reach 2,000 calories per person per day until the 1820s. Today, the global average is approaching 3,000 calories, and obesity is an increasing problem—even in sub-Saharan Africa.

      Almost 90 percent of people worldwide in 1820 were illiterate. Today, over 90 percent of humanity is literate. As late as 1870, the total length of schooling at all levels of education for people between the ages of 24 and 65 was 0.5 years. Today, it is nine years.

      These are the basics, but don’t forget other conveniences of modern life, such as antibiotics. President Calvin Coolidge’s son died from an infected blister, which he developed while playing tennis at the White House in 1924. Four years later, Alexander Fleming discovered penicillin. Or think of air conditioning, the arrival of which increased productivity and, therefore, standards of living in the American South and ensured that New Yorkers didn’t have to sleep on outside staircases during the summer to keep cool.

      So far, I have chiefly focused only on material improvements. Technological change, which drives material progress forward, is cumulative. But the unprecedented prosperity that most people enjoy today isn’t the most remarkable aspect of modern life. That must be the gradual improvement in our treatment of one another and of the natural world around us—a fact that’s even more remarkable given that human nature is largely unchanging.

      Let’s start with the most obvious. Slavery can be traced back to Sumer, a Middle Eastern civilization that flourished between 4,500 BC and 1,900 BC. Over the succeeding 4,000 years, every civilization at one point or another practiced chattel slavery. Today, it is banned in every country on Earth.

      In ancient Greece and many other cultures, women were the property of men. They were deliberately kept confined and ignorant. And while it is true that the status of women ranged widely throughout history, it was only in 1893 New Zealand that women obtained the right to vote. Today, the only place where women have no vote is the Papal Election at the Vatican.

      A similar story can be told about gays and lesbians. It is a myth that the equality, which gays and lesbians enjoy in the West today, is merely a return to a happy ancient past. The Greeks tolerated (and highly regulated) sexual encounters among men, but lesbianism (women being the property of men) was unacceptable. The same was true about relationships between adult males. In the end, all men were expected to marry and produce children for the military.

      Similarly, it is a mistake to create a dichotomy between males and the rest. Most men in history never had political power. The United States was the first country on Earth where most free men could vote in the early 1800s. Prior to that, men formed the backbone of oppressed peasantry, whose job was to feed the aristocrats and die in their wars.

      Strange though it may sound, given the Russian barbarism in Ukraine and Hamas’s in Israel, data suggests that humans are more peaceful than they used to be. Five hundred years ago, great powers were at war 100 percent of the time. Every springtime, armies moved, invaded the neighbor’s territory, and fought until wintertime. War was the norm. Today, it is peace. In fact, this year marks 70 years since the last war between great powers. No comparable period of peace exists in the historical record.

      Homicides are also down. At the time of Leonardo Da Vinci, some 73 out of every 100,000 Italians could expect to be murdered in their lifetimes. Today, it is less than one. Something similar has happened in Belgium, the Netherlands, Switzerland, Germany, Scandinavia, and many other places on Earth.

      Human sacrifice, cannibalism, eunuchs, harems, dueling, foot-binding, heretic and witch burning, public torture and executions, infanticide, freak shows and laughing at the insane, as Harvard University’s Steven Pinker has documented, are all gone or linger only in the worst of the planet’s backwaters.

      Finally, we are also more mindful of nonhumans. Lowering cats into a fire to make them scream was a popular spectacle in 16th century Paris. Ditto bearbaiting, a blood sport in which a chained bear and one or more dogs were forced to fight. Speaking of dogs, some were used as foot warmers while others were bred to run on a wheel, called a turnspit or dog wheel, to turn the meat in the kitchen. Whaling was also common.

      Overwhelming evidence from across the academic disciplines clearly shows that we are richer, live longer, are better fed, and are better educated. Most of all, evidence shows that we are more humane. My point, therefore, is a simple one: this is the best time to be alive.