For years, the question of whether health insurance directly influences death rates has sparked heated discussions, particularly in the context of the United States’ health care debates. In the midst of such a polarising issue, researchers like Richard Kronick in 2009, set out to determine whether there was a definitive link between health insurance and mortality. The answer, it seemed, was less than conclusive at the time, muddied by numerous confounding factors and a lack of comprehensive data. However, more recent research, bolstered by real-world experiments, has now shifted the consensus toward a resounding yes.
Early Research and the Complexity of Mortality
When Richard Kronick, a health policy expert, published his study in 2009, the findings were surprising to many. In a time when debates over the Affordable Care Act (ACA) were heating up, Kronick’s research suggested there was limited evidence to support the claim that health insurance directly affected mortality rates. His study criticised earlier, widely cited research from the Institute of Medicine, which had suggested that 18,000 deaths annually could be attributed to a lack of health insurance in the U.S. Kronick’s study, however, found that this assertion was “almost certainly incorrect.”
The issue, it seemed, was that mortality, particularly in the U.S., was influenced by a multitude of factors beyond insurance status. Lifestyle choices, socioeconomic status, and pre-existing health conditions all played a role. Even more intriguing was the possibility that some uninsured individuals, particularly those with fewer medical problems, might live longer due to their relative risk aversion. The lack of definitive evidence on mortality left a gap in the political debate, with some critics questioning the true significance of health insurance in preventing deaths.
The ACA and Real-World Evidence
The passing of the Affordable Care Act (ACA) in 2010, which expanded Medicaid in participating states, gave researchers an unexpected opportunity to assess the effects of health insurance on mortality in real time. The Supreme Court’s ruling allowed some states to opt out of expanding Medicaid, effectively creating a natural experiment. According to Benjamin Sommers, a health economist at Harvard, several studies showed that states that expanded Medicaid saw a noticeable decline in mortality rates, particularly among older adults.
One such study, cited by the health economist, found an 8% drop in mortality among older adults in states that expanded Medicaid, leading to the conclusion that the ACA was likely saving lives. This was a significant development, marking the first robust evidence that health insurance, at least in the form of Medicaid, could have a tangible impact on survival rates. A separate study, also cited by Sommers, found that the expansion of dependent coverage for young adults contributed to a decrease in disease-related deaths.
IRS Data Confirms the Findings
In 2017, a unique experiment provided further clarity. The IRS inadvertently created a randomised control trial when it sent letters to 4 million taxpayers who had previously paid a penalty for not having insurance under the ACA mandate. The letters encouraged recipients to sign up for insurance. Researchers tracked the outcomes of those who responded and compared them to a control group that did not receive the letters. The results were striking: those who obtained insurance had a significantly lower mortality rate over the following two years, particularly among those aged 45-64.
This study, according to Jacob Goldin, a law professor at the University of Chicago, “finished it for me.” The evidence was now strong enough to conclude that health insurance did, in fact, reduce mortality rates. However, the precise reasons for this effect remain unclear. Goldin speculates that insurance might facilitate earlier treatment for life-threatening conditions or open access to preventative care that could be life-saving.
The growing body of evidence has now reached a point where experts no longer question the role of insurance in saving lives. A 2025 study published in the Annual Review of Public Health unequivocally supports this conclusion, citing a decade’s worth of data showing a clear link between health insurance and improved health outcomes.
Despite this, the political discourse remains divisive. While researchers affirm that health insurance is a matter of life and death, certain political figures continue to downplay its significance, often using sweeping statements to dismiss the issue altogether.
