The impact of education on life expectancy

Despite spending far more on healthcare per capita than any other OECD (economically advanced) nation, the United States consistently lags behind in key health outcomes and access metrics. Life expectancy is lower, and infant mortality rates are higher in the U.S. compared to peer countries. This disparity is partly due to the lack of universal healthcare coverage, leaving millions uninsured or underinsured, which often delays or prevents necessary care. The complex, fragmented system, driven by a mix of private and public insurance, also creates administrative inefficiencies and high costs, with a significant portion of spending going towards administrative overhead rather than direct patient care. Furthermore, disparities in access and quality of care based on income, race, and geographic location contribute to poorer outcomes for vulnerable populations, widening the gap with other developed nations that prioritize equitable access and preventative care.

The COVID-19 pandemic provides one example of how the U.S. healthcare system fails its most vulnerable citizens. The pandemic caused a significant decline in life expectancy in the United States, far exceeding the average decrease observed in other OECD nations. Between 2019 and 2021, U.S. life expectancy dropped by roughly 2.7 years, a staggering decline not seen in generations. While other OECD countries also experienced decreases, their average decline was significantly smaller, around 0.56 years.

Socioeconomic factors, particularly wealth and education, exert a profound influence on life expectancy in the United States creating a stark gradient where higher status correlates with longer, healthier lives. Individuals with higher incomes have significantly better access to quality healthcare, including preventative services, specialist care, and advanced treatments, often through comprehensive employer-sponsored health insurance.

In the U.S., higher educational attainment is consistently linked to higher life expectancy. Moreover, the gap in life expectancy between those with high and low levels of education has been increasing in recent decades. As a result, gains in life expectancy have primarily benefited highly educated individuals with declining or stagnant life expectancy for lower education groups. Higher education leading to greater income and reduced exposure to health risks can help explain the correlation.

However, previous research primarily focused on national-level trends, and lacked detail at the local (e.g. county) level. The absence of detailed information could hamper more local insights and targeted interventions. For example, more granular data could identify populations and areas where increased educational support could have the greatest impact on life expectancy. A new paper attempted to address this gap by examining the relationship between life expectancy and education at the county level.

Using data from the National Vital Statistics System (deaths) and the Census (education), researchers estimated age-specific mortality rates by educational attainment, county, sex, age, and year from January 1, 2000, to December 31, 2019. The mortality rates were converted into life expectancy at age 25 for broken down at the country level. There were four educational attainment categories:

• Less than high school
• High school graduate (including equivalency)
• Some college (including associate degrees)
• College graduate (including graduate/professional degrees)

These data reaffirmed the national trends described above (Figure 1). There was a clear "educational gradient" in life expectancy with higher education correlated with higher life expectancy at age 25: College graduates > Some college (by 0.3 to 2.0 years) > High school graduates (by 4.1 to 4.9 years)> Less than high school (by 3.4 to 5.1 years). Moreover, life expectancy increased from 2000-2019 for college graduates (+2.5 years), some college (+0.7 years), and high school graduates (+0.3 years), but was unchanged for those with less than a high school education (0.0 years).

At the country level, there was substantial variation in life expectancy between counties, even within the same educational attainment groups. For example in 2019, the interquartile range (IQR) for life expectancy was 67.4-72.1 years for those with less than high school education, compared to 82.3-84.6 years for college graduates. Thus, the between country variation was largest for those with the least education. 

There were some interesting geographical patterns that emerged at the country-level across educational groups. Counties in central Colorado consistently showed relatively high life expectancy across all education levels. On the other hand, counties in the Southeast, parts of Appalachia, and parts of South Dakota showed relatively low life expectancy, especially pronounced for those with less than a high school education. Overall, the educational gradient was present in the vast majority of counties.

The authors concluded that educational disparities in life expectancy are significant, widespread, and increasing, both nationally and within most US counties, and that further research is needed to investigate how to mitigate barriers to good health for people with lower educational attainment so as to achieve the ultimate goal of improving health and increasing lifespans for all, particularly those with lower educational attainment.

In summary, the educational gradient in life expectancy is consistently observed (in agreement with previous studies), substantial geographic variation exists, especially for the least educated, and life expectancy gains have been unequal, favoring those with higher education.

Figure 1. U.S. estimated life expectancy by educational attainment from 2000 to 2019. In the upper panel, the four categories of educational attainment are 1) college graduate (purple), 2) some college (orange), 3) high school graduate (green), and 4) less than high school (blue). The shaded areas are the 95% uncertainty intervals. The time span from 2000 to 2019 is on the x-axis. The lower panel shows the difference in life expectancy between college graduates and less than high school educational categories.