1. We have doubled human life expectancy over the past century.
One hundred years ago, the average human life expectancy was around 30 years. In the United States during the last major pandemic, she was 41 years old. Today, the global life expectancy is 72 years, and in some parts of the world it is approaching 90. We have essentially given ourselves an extra life in just a century. A significant part of this change has come from the reduction in infant mortality. It doesn’t matter whether you are rich or poor, live in the city or are a hunter-gatherer – two in five of your children will die before they reach adulthood. Now, childhood has become the safest time in your life.
We are also extending the lifespan on the other end of the spectrum. In England, where we have the best data on these things, if you’ve gone through childhood in 1850, you can expect to live another 40 years to age 60. Today, a Briton who survives to the age of 20 can expect to live to the end of the 1980s. Globally, the percentage of people over 100 has quadrupled. over the past two decades. This is the most important thing that has happened to us during this time.
2. Don’t just thank the doctors; the toilets and sewers were equally important.
We have a natural tendency, when we think of improvements in human health, to focus on medical interventions – pills, x-rays, vaccines – but sometimes the breakthroughs that make the biggest difference are those behind the scenes. , those that don’t even look like major technological advancements.
One of the great killers of the 19th century was drinking water. In a big city like New York or London, you could drink a glass of water and die from a terrible disease like cholera in 48 hours. The improvements we needed to make weren’t happening in hospitals, they were happening in basic infrastructure. We had to find a way to clean up the drinking water supply in the big cities. The invention of toilets and the sewage system to which they are attached, the invention of water distribution systems and the chlorination of drinking water, these are major achievements in the history of human progress. They aren’t as sexy as your smartphone, but they actually have more of an impact on overall health and human lifespan.
3. Improving human health is not just a matter of science: we also need activists.
When we look at our history in terms of the extension of human life, we usually focus on scientific breakthroughs. But when you look at this story closely, you realize that something is missing. A medical or scientific breakthrough alone is not enough. You need to get this idea around and encourage people to embrace it before it can change the world. The best example is pasteurization.
In New York City in 1850, 60% of all deaths were in young children, and milk was the main culprit. We first solved this problem with chemistry – Louis Pasteur invented the technique of pasteurization in 1865. But it did not become the standard for milk in grocery stores in the United States until 1915 – fifty years later. that Pasteur made his breakthrough. And that’s because it took a whole generation of activists and legal reformers to get the idea that milk should be pasteurized – convincing consumers to buy it, convincing the dairy industry to change its practices. , pass laws, etc. When you look at the history of this kind of massive progress, you almost come close to things like social movements, like the abolition of slavery or the rise of universal suffrage. Ideas came from science, but they needed people to fight for them.
4. We have bad heroes in our society because progress in human health is measured in non-events.
There is this strange property about the progress of human health that is different from other more traditional forms of technological progress: it is measured in non-events, things that have not happened. With advancements in technology, the achievements are easy to see – the smartphone in your hand, the electric car in your garage – but the biggest advancements in health come in the form of events that didn’t happen: the smallpox infection that didn’t kill you at the age of two because we invented a vaccine; the glass of drinking water that didn’t give you a fatal case of cholera when you were 15 because we chlorinated the drinking water.
Our progress, in terms of health, is commensurate with all these changes that have kept us quietly safe over the years. We need to go the extra mile to go back and remember those accomplishments.
5. There is a strange paradox in the history of our extended human life expectancy.
One hundred years ago, when life expectancy was in the mid-1930s, there were just under two billion people on the planet. Today, they are nearly eight billion. And this rampant population growth did not come from people with more children; in fact, people are having fewer children per capita than ever. The growth of the world’s population is a result of people not dying – children live long enough to have children of their own, their parents live long enough to meet their great-grandchildren. As wonderful as life is, it creates its own set of problems for the planet. If we had simply maintained our population levels where they were in 1920, we would not be facing the climate crisis we are experiencing today. In a strange sense, today we have climate change because of two things: industrialization and the triumph of public health and medicine.
This begs the question: what comes next? Using existing approaches to treat the disease, we can probably push the average life expectancy into the 90s. But it’s hard to go much beyond that – the outer limit of human life seems to be around. about 110. A number of scientists, however, believe that there is a radical paradigm shift in our future. They believe that we can treat aging itself as some kind of disease that can be cured, allowing us to exceed this limit and possibly double life expectancy once again. But if we start living to be 150 years old, the impact on population growth could be terrifying. We need to decide as a species not only if we can cure aging, but if we really want it.
Steven Johnson is the bestselling author of thirteen books, including Where Good Ideas Come From, Farsighted, and The Ghost Map. He is the host and co-creator of the Emmy Award-winning PBS / BBC series How We Got to Now, and the host of the American Innovations podcast.
This article is reprinted with permission from the Next Big Idea Club, a subscription book club hosted by Malcolm Gladwell, Susan Cain, Daniel Pink and Adam Grant. The Next Big Idea Club provides key information on all the best new books through the Next Big Idea app, website and podcast. To listen to the audio version of this article, narrated by the author, and to enjoy other tidbits of books, download the Next Big Idea app.