Healthy States
The Medical Expansion, Life Expectancy, and Endogenous Directed Technical Change
Leon Huetsch, Dirk Krueger & Alexander Ludwig
NBER Working Paper, April 2026
Abstract:
We build a unified quantitative theory of increasing adult life expectancy and income growth in the last two centuries, and the emergence of a modern health sector in the 20th century. We interpret the data as three phases of a dynamic equilibrium in which households are initially poor, the price of health goods is prohibitively high, and life expectancy is stagnant. As technological progress fuels income growth, households commence consuming basic health goods and life expectancy rises in the first half of the 19th century. 100 years later, further directed technological progress leads to the emergence of a modern health sector. Through the lens of the model, the quality-adjusted relative price of modern health goods declined by about 2.5% per year between 1940 and 2020 while the model-implied relative price that lacks quality adjustment increases in line with the BEA health price index. Counterfactual analyses suggest that almost one fourth of adult life expectancy gains between 1940 and 2020 are attributed to the emergence and expansion of modern health and that public spending on health R&D during World War II played an important role in the kickoff of the modern health sector.
Municipal water fluoridation, adolescent IQ, and cognition across the life course: Evidence from the Wisconsin Longitudinal Study
John Robert Warren et al.
Proceedings of the National Academy of Sciences, 21 April 2026
Abstract:
We investigate associations between community water fluoridation (CWF), adolescent IQ, and cognition across the life course using representative data from the US state of Wisconsin. Exposure is inferred from historical records on community water fluoridation; adolescent IQ is ascertained from state testing records; and cognition in later life is assessed as part of the Wisconsin Longitudinal Study [P. Herd et al., Int. J. Epidemiol. 43, 34–41 (2014).]. In contrast to studies cited in recent decisions to end CWF in Utah, Florida, and elsewhere, we find no evidence that CWF is negatively associated with adolescent IQ or adult cognitive functioning.
Early-Life Sugar Restrictions Reduce Genetic Disparities in Adult Adiposity
Tadeja Gracner et al.
NBER Working Paper, March 2026
Abstract:
Genetics confer 2–3-fold higher obesity risk through inherited mechanisms affecting appetite and metabolism, with pathways particularly modifiable during the first 1,000 days of life. We leverage the end of UK sugar rationing in September 1953, a sharp discontinuity in early-life sugar exposure by conception date, to examine whether sugar restriction mitigates genetically determined obesity risk using UK Biobank data linking an obesity polygenic index with adiposity phenotypes. Without rationing, high genetic risk individuals had triple the obesity prevalence of low-risk counterparts. Restriction through age two narrowed this disparity by 40%, operating through visceral rather than general adiposity, and was concentrated among high-risk adults with above-median adiposity levels. Early nutritional environments can alter inherited obesity trajectories, pointing to targeted early-life interventions to reduce genetically determined health inequalities.
The rhythm of aging: Stability and drift in the individual rate of senescence
Silvio Patricio
Proceedings of the National Academy of Sciences, 14 April 2026
Abstract:
Human aging is marked by a steady rise in the risk of dying with age -- a process demographers call senescence. Over the past century, life expectancy has risen dramatically, but is this because we are aging slower, or simply starting it later? Vaupel hypothesizes that the pace at which individuals age may be constant, with gains in longevity coming from the delayed onset of senescence rather than its slowing down. We test this idea using a framework that decomposes the pace of senescence into three components: a biological baseline, a long-term trend, and the cumulative impact of period shocks. Applying this to cohort mortality data above age 80 from 12 countries, we find that once period shocks are accounted for, there is no statistical evidence of a long-term trend, consistent with Vaupel’s hypothesis. Analyses using lower starting ages yield the same qualitative conclusion. Rather than indicating a change in the process that drives senescence, these variations are consistent with echoes of shared historical events. These results suggest that while longevity has shifted, the rhythm of human aging may be conserved.
E-Cigarette Flavor Restrictions’ Effects on Tobacco Product Sales
Abigail Friedman et al.
American Journal of Health Economics, Spring 2026, Pages 377-411
Abstract:
More than 385 US localities and 7 states have implemented restrictions on sales of flavored electronic nicotine delivery systems (ENDS), yet these policies’ effects remain unclear. Utilizing comprehensive data on tobacco product flavor policies linked to retail sales data from January 2018 through March 2023, we estimate the effects of these restrictions. Our findings reveal that ENDS flavor restrictions yield substantial decreases in total ENDS sales, primarily owing to significant declines in flavored ENDS sales alongside nonsignificant increases in unflavored ENDS sales. Further analyses find that ENDS flavor restrictions increase sales of combustible cigarettes, a more harmful product: 11 to 15 additional cigarettes are purchased for every 1 less 0.7 mL ENDS pod sold because of these policies. This uptick in cigarette sales stems primarily from non-menthol cigarettes and includes brands disproportionately used by underage youth. These findings suggest that the public health benefits from reducing ENDS sales via flavor restrictions may be offset by the public health costs of consequent increases in cigarette consumption.
A µ-opioid receptor superagonist analgesic with minimal adverse effects
Juan Gomez et al.
Nature, forthcoming
Abstract:
Developing safe and effective pain medications is an ongoing challenge for human health. Agonists for the µ-opioid receptor (MOR) are essential pain medications, but their high intrinsic efficacy also induces adverse side effects, including respiratory depression, constipation, tolerance, dependence, withdrawal and addiction. Strategies to limit adverse effects traditionally include developing MOR agonists that have low intrinsic efficacy or that preferentially activate G-protein signalling over β-arrestin signalling. Here we identify a novel MOR agonist with supramaximal intrinsic efficacy and a unique pharmacological profile that produced effective analgesia in rodents with minimal adverse effects. N-desethyl-fluornitrazene (DFNZ) was derived from a class of synthetic benzimidazole opioids called nitazenes. DFNZ has impaired brain penetrance, a unique spatiotemporal MOR cellular signalling profile, and diminished efficacy at the MOR–galanin 1 receptor (GAL1) heteromer. DFNZ does not induce respiratory depression, tolerance or MOR downregulation after repeated exposure. Compared with other MOR agonists, DFNZ has limited effects on dopamine neurotransmission in nucleus accumbens and weaker reinforcing effects in the drug self-administration procedure. These results provide novel insights about MOR and nitazene pharmacology, have important implications for pain and addiction treatment, and challenge the prevailing dogma that high-efficacy MOR agonists cannot constitute safe and effective therapeutic agents.
Suicide Mortality Among Adolescents and Young Adults After Launch of a Suicide and Crisis Lifeline
Vishal Patel, Michael Liu & Anupam Jena
Journal of the American Medical Association, forthcoming
Background: Suicide remains a leading cause of death among adolescents and young adults in the US. In July 2022, the US launched the 988 Suicide and Crisis Lifeline, replacing the 10-digit 1-800-273-TALK number with a 3-digit number and investing more than $1.5 billion to expand crisis center capacity and workforce nationwide. In the subsequent 3 years, contacts to the lifeline more than doubled, with disproportionately higher use among adolescents and young adults. Whether population-level suicide mortality in this group changed after launch of the 988 Lifeline is unknown.
Methods: This study analyzed quarterly suicide mortality among individuals aged 15 to 34 years using the National Vital Statistics System (1999-2024), a registry of all US death certificates. Suicide deaths were identified using Statistical International Classification of Diseases and Related Health Problems, Tenth Revision underlying or contributing cause-of-death codes U03 and X60–X84. Data from January 1999 through June 2022 were used to model expected suicide mortality in the absence of the July 2022 launch of the 988 Lifeline. Expected postlaunch suicide mortality was forecasted using seasonal autoregressive integrated moving average models that accounted for secular trends and seasonality. Using Substance Abuse and Mental Health Services Administration state-level 988 Lifeline performance reports, states were ranked by relative change in monthly total answered 988 calls from October through December 2024 compared with July through September 2022, and analyses were stratified by the 10 states with the largest and smallest increases. Differences between observed and expected mortality from July 2022 through December 2024 were calculated. Several sensitivity analyses were conducted. First, the analysis was repeated among adults 65 years or older, who were less likely to use the 988 Lifeline and would be expected to experience a smaller reduction in suicide mortality. Second, analyses examined a cause of death that is unlikely to be affected by crisis services (malignant neoplasms, the leading natural cause of death among adolescents and young adults). Third, changes in youth and adolescent suicide deaths were analyzed for England, where no analogous national crisis line transition occurred during the study period. Fourth, analyses assessed whether including the COVID-19 pandemic period (2020-2022) in the baseline model influenced the counterfactual forecast by refitting the model on prepandemic data only. This study was exempted from human participants review by the Harvard Medical School Institutional Review Board given the use of deidentified, public data. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline. Analyses were 2 sided, and significance was defined as α = .05.
Results: From July 2022 through December 2024, nationwide observed suicide mortality among individuals aged 15 to 34 years was lower than expected based on pre–988 Lifeline trends. During this period, 35 529 suicides were observed compared with 39 901 (95% CI, 38 924-40 878) expected suicides, corresponding to an 11.0% (95% CI, 8.7%-13.1%) reduction or 4372 (95% CI, 3395-5349) fewer suicides. The 10 states with the largest increases in answered 988 calls after the launch had a 146.2% increase in monthly calls (from 32 635 to 80 338), whereas the 10 states with the smallest increases had a 23.6% increase in monthly calls (from 39 835 to 49 226). Reductions in observed-to-expected suicide mortality among those aged 15 to 34 years were significantly greater in the 10 states with the highest uptake (−18.2% [95% CI, −21.1% to −15.2%]) than in the 10 states with the lowest uptake (−10.6% [95% CI, −13.2% to −7.9%]). In sensitivity analyses, there was a significantly smaller reduction (−4.5% [95% CI, −7.1% to −1.8%]) in suicide mortality following launch of the 988 Lifeline among adults 65 years or older. No reductions in mortality from malignant neoplasms were observed and no comparable reductions in suicide mortality were observed in England, which did not change its national crisis services. After excluding the COVID-19 pandemic period from the baseline model, suicide deaths among individuals aged 15 to 34 years remained lower than expected based on trends before the initiation of the 988 Lifeline.
Can Money Buy Trust? Social Transfers and Trust During the Covid-19 Pandemic
Hyesang Noh & Ashley Fox
Policy Studies Journal, forthcoming
Abstract:
The United States was among the countries that increased social spending the most during the pandemic, including by adopting new cash transfer schemes. Yet, little is known about the impact of these newly implemented or augmented benefits on citizen trust in public health institutions. Grounded in policy feedback literature and research on attitudinal spillover, we hypothesize that receiving social transfers during the pandemic increased trust in health institutions, with potentially heterogeneous effects across household income and political affiliation. Employing a difference-in-differences model and using the Understanding America Study dataset, we find no overall effect of receiving Stimulus Fund or SNAP benefits on trust in health institutions. However, we observe significant heterogeneity: Republicans -- especially those with middle and high incomes -- tend to decrease their trust after receiving the Stimulus Fund. Independents and respondents with other political affiliations also decrease trust after receiving the SNAP, although the estimates are only marginally statistically significant. Taken together, results suggest that while universalistic social policies are often believed to be broadly politically popular and generate positive feedback effects, their impacts may be limited or heterogeneous depending on political affiliation.