Extending life expectancy was one of the outstanding achievements of the 20th century. A baby born in 1900, when infectious disease outbreaks were a regular occurrence and chronic diseases like cancer, dementia and heart disease were barely understood, lived just 32 years, on average. A baby born in 2021, after more than a century of modern medical research, will live to an average of 71.
At the same time, fertility rates have plummeted worldwide. In 1950, the average woman gave birth to nearly five children. Today that number is just over two—barely enough to maintain a stable population.
Fewer parents mourn the loss of their infants, fewer children have parents snatched away in midlife and more grandparents get to meet their grandchildren. But despite this stunning progress, few people are jumping up and down with excitement. The usual response is pessimism and worry.
At the heart of this reaction is a shift. In the 20th century, improvements in public health and advances in modern medicine reduced infant and midlife mortality and boosted life expectancy. These extra years of life were gained when people were mainly in good health and at their most productive. Now, most life-expectancy gains in high-income countries arise from declining mortality rates after 70 years of age, and a growing chance of living into your 90s. And for more and more people, the extra years of life coincide with declining health and economic inactivity.
Policymakers worry that this shift will lead to a dwindling workforce that’s unable to support the needs of an ever-expanding older population, including their needs for income, healthcare and living assistance. The fear is that pension deficits will become unsustainable, health expenditures will rise and economic growth will decline. By 2050 gross domestic product (GDP) per capita will drop by an average of eight percent for the nations of the Organization for Economic Cooperation and Development (OECD), the group predicts, plummeting 15 percent in South Korea and Italy and more than 20 percent in Spain.
When only a minority can expect to live to old age, it isn’t worth it, economically speaking, for society to invest in ensuring they live long, healthy and productive lives into their 80s. When it is the majority, it becomes an imperative.
If we are to avoid the worst predictions of an aging society, we need to focus on creating a longevity society that supports the length of life we can now expect. We need radical adjustment and adaptation to ensure life isn’t only longer, but also healthier, productive and engaging for longer. With global life expectancy exceeding 70, and half of children born today in high-income countries expected to live into their 90s, the first longevity revolution has ended—the young can now expect to become the old. A second longevity revolution must now begin, aimed at changing how we age.
A historic miscalculation
In 1798 the renowned economist and demographer Thomas Malthus argued that “the power of population is so superior to the power of the Earth to produce subsistence ... that premature death must in some shape or other visit the human race.” Malthus feared that society would be unable to provide the resources that extra mouths require and that overpopulation would inevitably result in famine, disease and war. Similarly, many in our aging society fear that we will be unable to provide the resources that the extra years of longevity demand.
Malthus’s insights have been hugely influential and continue to resonate as the world wrestles with the implications of climate change. But Malthus wrote at a time when the global population was approaching one billion; today it exceeds eight billion.
Central to Malthus’s near-term miscalculation was his failure to foresee the impact of the then-nascent Industrial Revolution. A powerful mix of ingenuity, innovation, investment and institutional change led to increases in productivity that helped provide additional resources to support a larger population. As a result, resources increased to levels that helped boost investment in health and education, leading to further gains in productivity, life expectancy and population.
To create a second longevity revolution, we need a mix just as powerful. Until now the proportion of lifespan that is healthy has remained approximately the same, even as life expectancy has increased, though the details differ in different countries. Increases in life expectancy have transformed the global burden of disease so that now the most common causes of death and illness globally are predominantly those whose incidence increases with age—cardiovascular disease, cancer, pulmonary disease, dementia, and so forth. The biggest lifetime health burden a newborn child will face is these aging-related diseases.
Medical progress has achieved wonders at keeping us alive longer, but not while keeping us healthier. We have hit diminishing returns. We need a new approach.
Daria Kirpach/Salzmanart.com
Improving how we age
Malthus’s pessimism has echoes today in the pessimism around the economic prospects of an aging society. His mistake may echo as well. Whatever the merits of his logic, he dramatically underestimated humanity’s ability to support a large population. Might the same be true of an aging society?
When people talk about artificial intelligence and climate change, they often emphasize the need for radical adjustment and adaptation. But talk about the challenges of an aging society rarely goes beyond raising the retirement age, cruise ships, care homes and adult diapers.
Rather than obsessing over all those people who are now older than 65, we need to focus on the future—specifically, what to do about today’s five-year-olds, who have extremely good odds of living to 65 years and beyond. Specifically, there’s an urgent need to ensure that our healthspan—the number of years we spend in good health—extends to match our new lifespan.
Improving how we age offers the prospect of enormous benefits for health and well-being as well as the economy. Using economic tools to place a dollar value on health gains, my colleagues and I estimate that slowing down the rate at which Americans age enough to boost life expectancy by one year, while also lowering morbidity rates, would yield $37 trillion of current and future welfare. Crucially, the analysis reveals that lowering morbidity to the point where healthy life expectancy is the same as life expectancy is far more valuable than any further increases in life expectancy.
Tackling how we age requires a major shift in how we think about health. The gains in life expectancy over the 20th century came from remarkable progress in tackling various diseases such as typhus, smallpox, cholera and tuberculosis. Health systems around the world have responded to these breakthroughs by successfully intervening to treat disease and thereby boosting life expectancy.
Today we need to shift our focus to prevention and keeping people healthy. Aging-related diseases are chronic and long-lasting, so it is best to delay their incidence rather than intervene when they occur. Once an individual experiences one chronic disease, the likelihood of experiencing a second increases, leading to multiple morbidities. All this points to a focus on intervening upstream to prevent the incidence of aging-related diseases.
This is why there is so much excitement about the emerging field of geroscience and its recent advances illuminating the biological pathways of aging. The hope is that better understanding will ultimately lead to treatments and therapeutics that slow down the aging process keep us healthier for longer. The potential gains of focusing on the underlying aging process, rather than tackling myriad individual diseases, are large. Since aging is an underlying risk factor for multiple diseases, success in improving how we age leads to gains across multiple illnesses. The effect of reducing multiple diseases unlocks an important complementarity: the gains from reducing the risk of cancer are greater when you do not run the risk of experiencing dementia, and vice versa.
The economics of healthy aging
If we manage to keep ourselves healthy for longer, we unlock not only health benefits but economic ones as well. In response to growing life expectancy, governments worldwide are increasing the eligibility age for state pensions. In 1983, the U.S. began increasing the retirement age from 65 to its current 67. According to OECD data, 22-year-olds in Denmark will have to wait until they are 74 before collecting a state pension. However, these measures assume individuals are capable of working for that long; right now, around 80 percent of Americans are working at age 50, but by 65, it has fallen to around a third. If most people have already left the labor market, there would be no point in raising the state pension age—it would cause financial hardship for many people.
The reasons for withdrawing from the labor market are varied, but high among them is poor health—either for the individuals themselves or because they need to care for a family member. For instance, in the U.K., someone who is in their 50s is six times more likely to leave the labor force if they have a cardiovascular event than if they don’t. With an aging population, that makes preventive health measures ever more valuable.
The need to invest in health for the sake of the economy has become increasingly apparent as populations age. Over the past 10 years, most of the employment growth in high-income countries has come from workers aged over 50, and in the European Union, it’s more than 100 percent. As the population ages, so does the labor force, making health and GDP increasingly intertwined.
The gains we’ve already seen to life expectancy need to be matched with efforts to make life not just longer but healthier, productive and engaging for longer. This is the longevity imperative that societies face if they are to avoid rising healthcare costs, growing pension deficits and stalling economic growth. The required social changes that this longevity imperative demands are broad and profound. As with the transformation that undermined Malthus’s pessimistic predictions, we will need widespread ingenuity, innovation, investment and new institutions.
Advancements in geroscience promise to play a key role in helping us age better and reduce morbidity. Given that the richest Americans live more than 10 years longer than the poorest, it’s also clear that policies aimed at tackling socioeconomic inequalities are also key. These inequalities show that we already know how to slow down aging for some, and a priority must be ensuring this occurs for many. It would help to prioritize inexpensive treatments that benefit the many, rather than expensive treatments that radically prolong life for a few.
Katie Peek; Source: U.S. Census Bureau
An evergreen economy
Major cultural change will also be required. Ageism involves underestimating the capacity of older people and our own later years. The fact that an “aging society” is seen as a problem speaks volumes about ageism. But in a world where the young can now expect to become old, we need to invest in our own futures and cannot afford to be prevented by ageist attitudes. If we wish to age better, we cannot wait until we are old to start doing so. If we do not invest in our newly found longer lives, then we run the risk of spending them in poor health and with too few resources.
Much else needs to change. While there is much talk of a “silver economy” providing the resources older individuals require, there needs to be the development of an “evergreen economy” focused on supporting aging better. Currently, only around three percent of government health expenditures are on prevention. That needs to increase in a way that encourages innovation in prevention. As the health system shifts from focusing on disease to promoting health, this agenda will spread beyond hospitals and medics to include food and drink, public housing and transport, and much else.
If people work longer, they will also need to be skilled for longer, which will generate increased demand for education around lifelong learning and career transitions. The financial sector will also need to respond because longer careers will require a more complex pattern of accumulation and decumulation of financial assets than the current simple pension model. In addition, while the 20th century saw the growth of an enormous life insurance industry aimed at eliminating the financial risk of dying early, in the 21st century, as more people live to 100 and beyond, a new form of insurance will be required to ameliorate the risk of running out of money.
For the first time, the young can expect to live into their tenth decade or even longer. This makes radical social change inevitable. We are entering a potentially dramatic turning point in the human condition.
When infant mortality was the biggest health challenge, resources were focused on tackling that problem. As progress was made, attention shifted to the diseases of middle age. Now, the majority of people will become old, and increasing attention will be placed on geroscience and understanding aging-related diseases.
There is something different, however, about aging-related diseases, compared to infant or mid-life diseases. The better we age, the more valuable further improvements become. When we are ill in our 80s, living into our 90s holds limited appeal. But when we are healthy and productive in our 90s, we become interested in living beyond 100. There are increasing returns to improving how we age that didn’t exist for infant- or midlife-mortality improvements.
None of this implies that geroscience is guaranteed to deliver sporty 120-year-olds. The biological mysteries of aging may remain forever too complex to understand or manipulate. It does point, though, to the need to invest in improving our understanding of how we age. Given the life expectancy we can now expect, few things are as crucial to our individual and collective future. Humanity is entering a radically new era.
Explore the emerging science of healthspan in other stories in this special report.
