Falling Behind: The Growing Gap in Life Expectancy Between the United States and Other Countries, 1933–2021

Abstract

Objectives. To document the evolution of the US life expectancy disadvantage and regional variation across the US states.

Methods. I obtained life expectancy estimates in 2022 from the United Nations, the Human Mortality Database, and the US Mortality Database, and calculated changes in growth rates, US global position (rank), and state-level trends.

Results. Increases in US life expectancy slowed from 1950 to 1954 (0.21 years/annum) and 1955 to 1973 (0.10 years/annum), accelerated from 1974 to 1982 (0.34 years/annum), and progressively deteriorated from 1983 to 2009 (0.15 years/annum), 2010 to 2019 (0.06 years/annum), and 2020 to 2021 (–0.97 years/annum). Other countries experienced faster growth in each phase except 1974 to 1982. During 1933 to 2021, 56 countries on 6 continents surpassed US life expectancy. Growth in US life expectancy was slowest in Midwest and South Central states.

Conclusions. The US life expectancy disadvantage began in the 1950s and has steadily worsened over the past 4 decades. Dozens of globally diverse countries have outperformed the United States. Causal factors appear to have been concentrated in the Midwest and South.

Public Health Implications. Policies that differentiate the United States from other countries and circumstances associated with the Midwest and South may have contributed. (Am J Public Health. 2023;113(9):970–980. https://doi.org/10.2105/AJPH.2023.307310)

The United States suffers from a health disadvantage: the US population experiences poorer health than populations in other countries, and the disadvantage has grown over time.¹ One component of this phenomenon is the US life expectancy disadvantage: survival in the developed world has increased over the past century, but growth in US life expectancy has not kept pace with that of other industrialized countries. The gap with other countries widened dramatically after 2010, when life expectancy plateaued in the United States but continued increasing elsewhere.²

A recent demonstration of the US health disadvantage occurred during the COVID-19 pandemic, when the United States experienced more COVID-19 deaths than any other country and among the highest per capita death rates.³ US life expectancy decreased by 2.1 years between 2019 and 2021, the largest decrease in a century.^2–4 Other high-income countries experienced smaller decreases in life expectancy during the pandemic, widening the gap to historic levels.²

The US life expectancy disadvantage began decades ago but exactly when remains unclear. Studies typically date the onset to the 1980s or 1990s, raising intriguing research questions about events in history that might explain this timing. Researchers usually measure the US life expectancy gap in reference to “peer countries,” typically selecting high-income—and largely Western European or Anglo-Saxon—countries as the comparison group.^1,5–8 The implicit assumption is that less affluent or developing countries are unlikely to outperform the United States and cannot serve as a benchmark for documenting a US disadvantage. The validity of either assumption—that only high-income countries surpassed the United States and that the phenomenon began in the 1980s to 1990s—is unclear.

Clarifying the timing and geographic scale of the US life expectancy disadvantage is important groundwork for investigating potential causes. For example, knowing the years when changes occurred in the slope—the rate of change in US life expectancy—is a prerequisite for future studies of period and cohort effects. Comparing this “growth rate” with the slope in comparison countries would clarify when and how the US trajectory diverged. Furthermore, examining how life expectancy trends varied across the country can identify states where adverse life expectancy trends were geographically concentrated.

Several databases could help answer these questions but have not been examined with these aims. For example, the Population Division of the UN Department of Economic and Social Affairs has estimated life expectancy for 237 countries (and other geographic areas) for 1950 to 2021.⁹ The Human Mortality Database—maintained by the University of California, Berkeley, the Max Planck Institute for Demographic Research in Germany, and the French Institute for Demographic Studies—provides life expectancy estimates for more than 40 countries, including 22 populous countries with data from before 1950.¹⁰ Finally, the University of California, Berkeley maintains the US Mortality Database, which provides life tables for 1959 to 2020 for the 50 US states, the District of Columbia, and US Census Bureau regions.¹¹

In this study, I merged data from these 3 sources to document the history and geographic progression of the US life expectancy disadvantage over 8 decades, analyzing a longer period than most studies have considered and widening the scope beyond high-income countries. The study addressed 4 research questions (see subquestions in Table A, available as a supplement to the online version of this article at http://www.ajph.org):

• 1.Over the observation period, how many countries achieved higher life expectancy than the United States, when, and for how long?
• 2.How did the position (rank) of the United States relative to other countries change over time?
• 3.How did the slope (rate of increase in life expectancy) vary in the United States, and when did it diverge from the average slope in other countries?
• 4.How did life expectancy in the 50 states compare with other countries, and which states made the greatest contributions to adverse US life expectancy trends?

METHODS

I focused the analysis on countries that “surpassed” the United States (achieved higher life expectancy) in at least 1 year of the observation period. Because life expectancy estimates can be unstable for small populations, I examined data only for “populous” countries, defined here as those with populations greater than 500 000 (based on UN data⁹).

Data Sources

I obtained life expectancy estimates for the period before 1950 from the Human Mortality Database. That database provides pre-1950 life expectancy estimates for the United States, beginning in 1933; beginning earlier in 18 other countries, including Sweden (1751–), France (1816–), Denmark (1835–), Iceland (1838–), Belgium (1841–), Norway (1846–), the Netherlands (1850–), Scotland (1855–), Italy (1872–), Switzerland (1876–), Finland (1878–), Spain (1908–), Australia (1921–), Canada (1921–), the United Kingdom (1922–), and Northern Ireland (1922–); and beginning later in 4 countries: Portugal (1940–), Bulgaria (1947–), Japan (1947–), and New Zealand (1948–).

I extracted life expectancy estimates for the United States and 236 other countries for the period of 1950 to 2021 from the July 2022 UN Population Division data release.⁹ The UN derived these estimates from official life tables, registered deaths, and modeling methods described elsewhere.^12,13 The UN reported life expectancy estimates for countries and areas as defined in the statistical codes of the UN Secretariat,¹⁴ which included territories (e.g., Puerto Rico) and some areas that are not universally recognized as countries (e.g., Taiwan, Hong Kong, Macao). The UN provided estimates for countries under their current names (e.g., Czechia, Slovenia) and for previous years when those areas were circumscribed in other countries (e.g., Czechoslovakia, Yugoslavia). They combined preunification (pre-1990) data for East and West Germany. I used World Bank sources to classify the income status of countries and to designate “centrally planned,” or Communist, economies.^15,16

I obtained life expectancy estimates for US states for 1959 to 2019 from the US Mortality Database.¹¹

Data Analysis

I grouped countries by continent¹⁷ and US states by US Census Bureau regions (n = 4) and divisions (n = 9).¹⁸ I determined the period of “dominance” (the calendar years when a country’s life expectancy exceeded US life expectancy), total years of dominance during 1950 to 2021, and the country’s income status at the time of dominance.

For each year, I examined the gap between US life expectancy and that of the populous country with the highest life expectancy (Norway in 1950–1962 and 1976–1977, Sweden in 1963 and 1965–1975, the Netherlands in 1964, Japan in 1978–2007, Macao in 2008–2010, and Hong Kong in 2011–2021). For the period 1959 to 2019, I compared estimates of life expectancy by state from the US Mortality Database and by country from UN data to determine where states would rank if they were countries (excluding the United States and other states when determining rankings). For context, I identified 4 “adjacent” populous countries with the most comparable life expectancy: 2 higher and 2 lower. I included countries that never surpassed the United States only for this contextual analysis.

To examine temporal trends in the United States and other populous countries, I calculated year-over-year absolute changes in life expectancy and mean year-over-year changes for the entire 70-year period (1950–2021), for each decade, and for 6 periods (phases) with distinctly different growth rates in US life expectancy. For all 4 measures (yearly changes and mean changes for 1950–2021 and each decade and phase), I also calculated the median value for mean changes in life expectancy among populous countries. In calculations of slopes and rankings, I excluded values for countries with populations below 500 000 during the years of analysis. Because estimates from the UN and US Mortality Database began with 1950 and 1959, respectively, measures of annual increases began with 1951 and 1960.

RESULTS

Growth in US life expectancy during 1950 to 2021 (Figure 1a) occurred in 6 phases with distinctly different slopes (growth rates): phase 1 (1950–1954), a period of brisk growth (0.21 years/annum); phase 2 (1955–1973), when growth slowed by half (0.10 years/annum); phase 3 (1974–1982), when the growth rate rebounded (0.34 years/annum); phase 4 (1983–2009), when growth slowed by half (0.15 years/annum) and remained slow for more than 2 decades; phase 5 (2010–2019), when life expectancy plateaued (0.06 years/annum); and phase 6 (2020–2021), when life expectancy decreased sharply (–0.97 years/annum) during the COVID-19 pandemic.

FIGURE 1—

Change Over Time in (a) US Life Expectancy and (b) US Life Expectancy Gap and Rank Relative to Populous Countries (Population > 500 000): 1950–2021

Note. Phase 1 = 1950–1954; phase 2 = 1955–1973; phase 3 = 1974–1982; phase 4 = 1983–2009; phase 5 = 2010–2019; phase 6 = 2020–2021. Bars plot the difference in life expectancy between the United States and the populous country (population > 500 000) with the highest life expectancy in the given year. The country with the highest life expectancy was Norway in 1950–1962 and 1976–1977, Sweden in 1963 and 1965–1975, the Netherlands in 1964, Japan in 1978–2007, Macao in 2008–2010, and Hong Kong in 2011–2021. The line graph plots US rank relative to other populous countries, with higher rank denoting lower US life expectancy.

Source. Author’s calculations based on UN data.⁹

Life Expectancy

In 1933 (when US estimates first appear in the Human Mortality Database), US life expectancy ranked 8th highest among 16 populous countries, behind the Netherlands, Norway, Australia, Sweden, Denmark, Switzerland, and Canada. These countries, along with the United Kingdom, generally maintained higher life expectancy than the United States from the 1930s through World War II and the late 1940s.

In 1950, US life expectancy ranked 12th highest among populous countries in the UN database, and the gap with the top performer was 3.5 years (Figure 1b). When the US growth rate slowed in phase 2 (1955–1973), 19 countries surpassed the United States. By 1968, the US rank had fallen to 29th. The United States rebounded temporarily in the 1970s, recovering much of these losses; in 1976, US life expectancy ranked 13th among populous countries. However, the United States began losing ground to other countries in the early 1980s; between 1983 and 2009, US ranking among populous countries fell from 15th to 32nd, and the life expectancy gap with the top performer rose from 2.6 years to 4.7 years (Table B, available as a supplement to the online version of this article at http://www.ajph.org). During 2010 to 2019, when US life expectancy plateaued, 7 more populous countries surpassed the United States.

By 2019, the eve of the COVID-19 pandemic, US life expectancy ranked 40th among populous countries—lower than in Albania and Lebanon—and the life expectancy gap with the top performer was 6.1 years. Large decreases in US life expectancy during the pandemic enabled 6 more populous countries to surpass the United States. In 2020, US life expectancy ranked 46th among populous countries, and the gap reached 7.8 years.

Life Expectancy Growth Rates

US ranking decreased because other populous countries averaged larger annual increases in life expectancy in 49 of the 70 years studied. As detailed elsewhere (Table C, available as a supplement to the online version of this article at http://www.ajph.org), the mean US growth rate was lower than median growth in other populous countries when analyzed on multiple measures: for the entire 7-decade period (1951–2021), in each individual decade but the 1970s, and in each phase except phase 3 (1974–1982). The US growth rate was outperformed by 48 populous countries during phase 4 (1983–2009) and by all populous countries but Cuba (n = 56) during phase 5 (2010–2019). Although growth slowed across many countries during phase 5, the median pace in populous countries (0.18 years/annum) was still triple that of the United States (0.06 years/annum), and other countries experienced smaller losses in life expectancy during phase 6 (COVID-19 pandemic).

Between 1933 and 2021, 56 populous countries on multiple continents achieved higher life expectancy than the United States (Figure 2; Figure A and Table D, available as a supplement to the online version of this article at http://www.ajph.org). Before 1950, most populous countries that outperformed the United States were in Northern and Western Europe, with a few exceptions (Australia, Canada, Israel, Latvia, New Zealand). However, in the 1950s and 1960s, Southern European (e.g., Greece, Italy, Spain) and additional Western European countries (e.g., Austria, France, Belgium, Germany, Ireland) surpassed the United States, as did several Eastern Bloc countries (e.g., Belarus, Bulgaria, Czechoslovakia, Lithuania, Ukraine). Asian countries also surpassed the United States, beginning with Japan and Hong Kong in the 1960s and followed by other East Asian countries in the 1990s and beyond. The United States was also surpassed by several Eastern European countries after 2000 and by Middle Eastern states, beginning with Kuwait in the 1990s and followed by Bahrain, Qatar, United Arab Emirates, and Lebanon after 2010. US life expectancy was surpassed by 11 middle-income and 9 Communist countries. Seventeen countries outperformed the United States for more than 50 years.

FIGURE 2—

Populous Countries That Achieved Higher Life Expectancy Than the United States and Calendar Years of Dominance: 1950–2021

Note. Shaded bars depict the calendar years during which populous countries (populations > 500 000) experienced higher life expectancy than the United States; interruptions in bars reflect periods when the United States recovered its advantage (experienced higher life expectancy). A more detailed version of this figure (Figure A, available as a supplement to the online version of this article at http://www.ajph.org) includes each country’s ranking, by year, among populous countries, showing how the relative position of countries surpassing the United States progressed over time.

Source. Author’s calculations based on UN data.⁹

State Contribution to US Changes

In 1959, when US Mortality Database estimates begin, Kansas and South Carolina had the nation’s highest and lowest life expectancy, respectively. Were these states countries, they would have ranked 5th and 34th among the world’s populous countries. Populous countries closest in life expectancy (“adjacent” countries) to Kansas were the Netherlands and Denmark (next highest life expectancy) and Switzerland and the United Kingdom (next lowest), whereas countries adjacent to South Carolina were Hungary and Bulgaria (higher) and Poland and Hong Kong (lower). Over the ensuing 60 years, US states experienced a diminished global position and greater divergence in life expectancy. By 2019, the state with the highest life expectancy, Hawaii, ranked 22nd—adjacent to Austria and Finland (higher) and the United Kingdom and Portugal (lower)—whereas the state with the lowest life expectancy, Mississippi, ranked 79th, adjacent to Mauritius and Bulgaria (higher) and Ukraine and Morocco (lower).

Increases in life expectancy between 1959 and 2019 differed across the 50 states (Table 1; Table E, available as a supplement to the online version of this article at http://www.ajph.org). Growth rates were generally highest in the Northeast (US Census divisions 1–2) and West (divisions 8–9) and lowest in South Central states (US Census divisions 6–7) and the Midwest (divisions 3–4), especially during phases 4 and 5 (Figure 3). In phases 3 to 5, strong growth occurred in the Atlantic coastal states of division 5 (from Delaware to Florida), but growth rates were low in West Virginia, that division’s 1 inland state. The Midwest experienced the lowest growth rates in phases 2 and 4 and accounted for more than half of the 17 states that experienced negative growth (i.e., decreases) in phase 5 (Table 1). All 50 states contributed to the national decline in phases 4 and 5: no state—even states with the highest growth rates—outperformed the US growth rate of the previous phase. Nor did any state match the median growth of populous countries in phases 2, 4, and 5 (except Hawaii and Nevada in phase 2). Patterns reversed during the US rebound in phase 3, when all states but Oklahoma outpaced median growth in populous countries.

TABLE 1—

Yearly Change in Life Expectancy in US States, United States (Total), and Populous Countries: 1960–2019 and Phases 2–5

Location	Increases in Life Expectancy (Years/Annum), by Period
	1960–2019	Phase 2 (1960–1973)	Phase 3 (1974–1982)	Phase 4 (1983–2009)	Phase 5 (2010–2019)
Populous countriesa (median)	0.21	0.20	0.24	0.23	0.18
United Statesb (mean)	0.15	0.11	0.34	0.15	0.06
Region 1: Northeast
Division 1: New England
Connecticut	0.16	0.15	0.26	0.18	0.03
Massachusetts	0.17	0.12	0.34	0.17	0.06
Maine	0.15	0.15	0.38	0.14	−0.05
New Hampshire	0.16	0.13	0.36	0.17	−0.04
Rhode Island	0.16	0.14	0.35	0.15	0.03
Vermont	0.16	0.13	0.33	0.19	−0.02
Division 2: Mid-Atlantic
New Jersey	0.18	0.13	0.29	0.20	0.06
New York	0.19	0.14	0.29	0.22	0.13
Pennsylvania	0.15	0.12	0.35	0.15	0.04
Region 2: Midwest
Division 3: East North Central
Illinois	0.16	0.08	0.37	0.17	0.08
Indiana	0.11	0.06	0.36	0.11	−0.02
Michigan	0.14	0.06	0.33	0.15	0.02
Ohio	0.12	0.08	0.33	0.12	−0.04
Wisconsin	0.14	0.14	0.31	0.14	−0.04
Division 4: West North Central
Iowa	0.12	0.10	0.34	0.12	−0.03
Kansas	0.11	0.08	0.30	0.10	−0.01
Minnesota	0.15	0.14	0.34	0.15	−0.002
Missouri	0.11	0.06	0.35	0.11	0.00
Nebraska	0.13	0.11	0.29	0.13	−0.01
North Dakota	0.13	0.11	0.38	0.10	−0.01
South Dakota	0.13	0.14	0.29	0.14	−0.05
Region 3: South
Division 5: South Atlantic
Delaware	0.15	0.10	0.29	0.17	0.04
Florida	0.16	0.07	0.39	0.15	0.11
Georgia	0.17	0.08	0.44	0.15	0.08
Maryland	0.17	0.06	0.35	0.11	0.00
North Carolina	0.16	0.08	0.45	0.14	0.05
South Carolina	0.18	0.13	0.51	0.15	0.04
Virginia	0.18	0.14	0.39	0.17	0.08
West Virginia	0.09	0.06	0.36	0.07	−0.03
Division 6: East South Central
Alabama	0.12	0.10	0.41	0.07	0.03
Kentucky	0.10	0.05	0.34	0.08	−0.003
Mississippi	0.11	0.09	0.40	0.08	−0.02
Tennessee	0.11	0.07	0.38	0.08	−0.02
Division 7: West South Central
Arkansas	0.10	0.05	0.35	0.06	0.04
Louisiana	0.13	0.08	0.34	0.12	0.07
Oklahoma	0.08	0.06	0.20	0.07	0.05
Texas	0.14	0.05	0.34	0.15	0.09
Region 4: West
Division 8: Mountain
Arizona	0.17	0.18	0.36	0.14	0.07
Colorado	0.16	0.13	0.35	0.14	0.07
Idaho	0.14	0.12	0.33	0.14	0.03
Montana	0.16	0.14	0.39	0.13	0.05
Nevada	0.18	0.20	0.29	0.16	0.09
New Mexico	0.13	0.09	0.43	0.12	−0.05
Utah	0.14	0.12	0.31	0.14	0.01
Wyoming	0.14	0.08	0.40	0.12	0.04
Division 9: Pacific
Alaska	0.16	0.12	0.35	0.16	0.07
California	0.17	0.10	0.28	0.19	0.12
Hawaii	0.17	0.25	0.30	0.11	0.11
Oregon	0.15	0.14	0.35	0.13	0.06
Washington	0.16	0.13	0.36	0.14	0.07

Source. Author’s calculations based on US Mortality Database¹¹ and UN⁹ data. The table omits data on changes in life expectancy during phase 1 and early phase 2 (1955–1958), for which state-level life expectancy estimates were unavailable in the US Mortality Database.

^a Populations of > 500 000. Values for 10 countries were included only for years in which their populations exceeded 500 000; these included Bahrain (1990–), Cyprus (1953–), Macao (2007–), Kuwait (1966–), Luxembourg (2010–), Maldives (2020–), Montenegro (1965–), Qatar (1995–), Réunion (1974–), and United Arab Emirates (1975–).

^b State means are presented by US Census Bureau regions and divisions.¹⁸

FIGURE 3—

Mean Changes in Life Expectancy by State During (a) Phase 4, 1983–2009, and (b) Phase 5, 2010–2019: United States

Note. The maps depict mean changes in life expectancy per annum that states experienced over the years comprising phase 4 (1983–2009), when increases in US life expectancy slowed, and phase 5 (2010–2019), when US life expectancy stagnated.

Source. Author’s calculations based on US Mortality Database.¹¹

DISCUSSION

Studies of the US health disadvantage typically make comparisons with 15 to 30 high-income countries, consisting mostly of British Commonwealth (e.g., United Kingdom, Australia, Canada) and Western European “peer countries.”^1,2,5–8 I found that the 56 countries that outperformed the United States spanned the globe, from East Asia to Central and South America, Eastern Europe, and the Middle East. Moreover, 20 were middle-income or Communist countries when they surpassed the United States. Some developing countries experienced spectacular increases in life expectancy and now rank among the healthiest in the world. For example, in 1959, Hong Kong had lower life expectancy than South Carolina but by 2011 had the world’s highest life expectancy.

A 2013 National Research Council report explored 5 domains that might explain the US health disadvantage—health systems, individual behaviors, socioeconomic factors, the environment, and policies and social values—and with each domain found distinctive US characteristics that might contribute to poorer health.¹ Potential contributors included not only downstream, proximal factors such as obesity, substance abuse, and deficiencies in the US health care system but also upstream, macrostructural factors such as US policies. For example, countries with better health outcomes typically offer more generous social welfare and income support programs and enforce stronger regulations to protect public health and safety.^19,20

Explanations for the US life expectancy disadvantage must account for its timing—when in US history it began and why growth rates changed over particular years. Previous studies dated the onset to the 1980s or 1990s, prompting speculation about the roles of the obesity epidemic, Reagan era policies, and the opioid crisis that followed the 1996 licensing of OxyContin.⁷ However, I found that growth in US life expectancy began slowing as early as phase 2 (1955–1973), allowing 3 countries in the late 1950s and 16 countries in the 1960s to surpass the United States. The rebound in phase 3 (1974–1982) temporarily halted further losses, but the slowing that followed in phase 4 (1983–2009) allowed the United States to be surpassed by 3 countries in the 1980s, 2 countries in the 1990s, and 8 countries in the 2000s.

Understanding the complex reasons for these changes in slope will require further research. Some explanations^6,7,21,22 have emerged for phase 5 (2010–2019), the decade in which US life expectancy plateaued, allowing 7 more countries to surpass the United States. A 2021 report by the National Academies of Science, Engineering, and Medicine attributed the stagnation in US life expectancy to an increase in mortality rates in midlife (25–64 years). This increase, which no other country experienced, was caused primarily by US deaths from drug overdoses, alcohol-related causes, suicides, and cardiometabolic diseases.⁷

By 2019, the eve of the COVID-19 pandemic, 39 populous countries had higher life expectancy than did the United States. The gap with Hong Kong, which had the world’s highest life expectancy, was 6.1 years. Life expectancy in some US states was lower than in developing countries. In 2019, life expectancy in West Virginia and Mississippi was lower than in the State of Palestine. The large decrease in US life expectancy that occurred during the COVID-19 pandemic—larger than in all countries but Bulgaria and Slovakia²³—enabled 6 more countries to surpass the United States. By 2021, the gap with Hong Kong had reached 8.3 years.

Limitations

Limitations of this study include the reliance on life expectancy estimates from the UN Population Division and US Mortality Database, which, although validated,^12,24 are subject to errors that could potentially skew rankings and year-over-year changes. The inclusion of territories and countries with contested legal status could also affect rankings. The method used to define phases 1 to 5 may be less precise than determining inflection points and slopes through statistical modeling (e.g., Joinpoint Regression Program). Finally, data from countries with relatively small populations can provide important insights but are sometimes less generalizable to large countries like the United States, where scalability and cross-cultural adaptability pose greater challenges.

Public Health Implications

The pervasiveness of the US health disadvantage, which involves dozens of diseases and causes of death and has lasted decades, suggests that the problem is larger and more enduring than any single health problem (e.g., drugs, firearms, obesity) and likely involves upstream, systemic factors capable of producing widespread effects on health.¹ Health is not the only domain in which the United States has lost ground to other countries, further indication that systemic obstacles and policy choices may have impeded socioeconomic progress on a more fundamental level. For example, despite its vast aggregate wealth, the United States has the highest income inequality (e.g., Gini coefficient), greatest concentration of wealth, and highest poverty rate in the Organisation for Economic Co-operation and Development.²⁵ Since 1995, 17 Organisation for Economic Co-operation and Development countries have surpassed the United States on the share of the population with a tertiary education.²⁵ In 2018, US students ranked 32nd in math performance at aged 15 years.²⁵ Such declines may reflect the rise of neoliberal policies, beginning in the 1970s, which were intentional about promoting entrepreneurial freedom and deregulation, redistributing wealth from the middle to the upper class, and curbing government’s role in broadening access to education, health care, and human services.²⁶

Social and economic stresses, resulting in part from such policies, may help explain the geographic variation and slower growth in life expectancy observed in certain states. Although Appalachia and the Deep South (i.e., South Central and South Atlantic divisions) typically rank lowest on life expectancy and other health statistics,²⁷ I found that the slowest growth in life expectancy occurred not only in South Central states but also in the Midwest. The Midwest accounted for more than half of US states that experienced a decline in life expectancy in 2010 to 2019. Other studies found that the increase in midlife mortality that followed 2010—much of it driven by drug overdoses, suicide, and liver disease—was disproportionately concentrated in the Industrial Midwest.^7,28,29 States in the Rust Belt and agricultural heartland endured the collapse of the manufacturing sector and the farm crisis, which claimed jobs and family farms, increased economic precarity, and potentially compromised health outcomes.^30,31 These states also underwent a political shift to more conservative policies on matters that affect health (e.g., Medicaid eligibility, tobacco taxes, social welfare).³² Studies show that states that adopted more conservative policies were more likely to experience stagnant or decreasing life expectancy and higher mortality even after adjustment for confounding variables.³²

Whether these factors are causally implicated in the US life expectancy disadvantage or the geographic variation observed here will require additional research using innovative study designs that can distinguish between mediators and confounding variables. A range of potential systemic explanations for the US health disadvantage should be considered. Structural racism, for example, produces deep health inequities among people of color but may also adversely affect the White population.³³ Investigators should also explore the contribution of diet, psychosocial factors, trauma, despair (particularly among young adults^34,35), disruptions in family structure, economic hypersegregation of communities, political polarization, erosions in social cohesion and trust, and harmful technological influences (e.g., social media), among others.

Although these research priorities are important, the US health disadvantage continues to claim lives in real time. The crisis has broad implications, affecting not only mortality but also morbidity, with ripple effects on health care costs, workforce productivity, and the economy. The gravity of the situation may justify intervention even before definitive evidence becomes available. A prudent first step would be to examine policies that have enabled other countries to consistently outperform the United States for decades.