Healthy Lives

Kevin Lewis

May 11, 2023

The Uptrend Effect: Encouraging Healthy Behaviors Through Greater Inferred Normativity
John Costello et al.
Journal of Marketing Research, forthcoming 


Only a minority of Americans are adequately engaging in activities experts recommend to curb preventable disease, such as consumption of healthful foods and regular physical exercise. This poses a challenge for policymakers and social marketers alike, given the substantial impact descriptive norms have on behaviors in the health domain. We propose a new way to address this challenge by identifying what we call the “uptrend effect.” This effect encourages descriptively non-normative, healthy behaviors through uptrend messaging that makes salient actual increased engagement in those behaviors over time without referencing an objective descriptive norm. Across seven experimental studies, including studies conducted in the field and measuring real behaviors, we demonstrate that uptrend messaging leads recipients to infer greater descriptive normativity for the target behavior, which subsequently improves engagement. We identify theoretically and practically relevant boundary conditions, showing that the uptrend effect is attenuated when the growth in a behavior is driven by a dissimilar group or when the message explicitly states a descriptive norm. We also demonstrate that uptrend messaging outperforms other norm-based approaches. Our theory and findings inform scholars, policy makers, and marketers by providing actionable and easy to implement techniques to encourage behaviors that improve consumer quality of life.

Cognitive activity at work and the risk of dementia
Nicolau Martin-Bassols et al.
Health Economics, forthcoming 


Dementia prevalence is projected to rise steeply in coming decades, producing tremendous burdens on families, and health and social services. Motivated by the need for further robust evidence on modifiable risk factors, we investigate the relationship between cognitive activity at work and later-life dementia. Using data from the US Health and Retirement Study matched to the O*NET occupational database, we find that a one standard deviation increase in the cognitive activity associated with one's longest held occupation is associated with a 0.9 percentage point reduction in (predicted) dementia, or a 24% reduction relative to the mean. This relationship is consistently found across model specifications and robustness tests. When controlling for individual fixed-effects we find that the association between dementia and work cognitive activity increases with age. Overall, our results provide some evidence in support of the inclusion of cognitive activity at work as a recognized modifiable risk factor for dementia.

Individual Empowerment, Institutional Confidence, and Vaccination Rates in Cross-National Perspective, 1995 to 2018
Wade Cole, Evan Schofer & Kristopher Velasco
American Sociological Review, forthcoming 


In the past decade, before the onset of the Covid-19 pandemic, rates of childhood vaccination against diseases such as measles, diphtheria, pertussis, and tetanus declined worldwide. An extensive literature examines the correlates and motives of vaccine hesitancy -- the reluctance or refusal to vaccinate despite the availability of vaccines -- among individuals, but little macrosociological theory or research seeks to explain changes in country-level vaccine uptake in global and comparative perspective. Drawing on existing research on vaccine hesitancy and recent developments in world society theory, we link cross-national variation in vaccination rates to two global cultural processes: the dramatic empowerment of individuals and declining confidence in liberal institutions. Both processes, we argue, emerged endogenously in liberal world culture, instigated by the neoliberal turn of the 1980s and 1990s. Fixed- and random-effects panel regression analyses of data for 80 countries between 1995 and 2018 support our claim that individualism and lack of institutional confidence contributed to the global decline in vaccination rates. We also find that individualism is itself partly responsible for declining institutional confidence. Our framework of world-cultural change might be extended to help make sense of recent post-liberal challenges in other domains.

Politicization of Science in COVID-19 Vaccine Communication: Comparing US Politicians, Medical Experts, and Government Agencies
Alvin Zhou, Wenlin Liu & Aimei Yang
Political Communication, forthcoming 


We compare the social media discourses on COVID-19 vaccines constructed by U.S. politicians, medical experts, and government agencies, and investigate how various contextual factors influence the likelihood of government agencies politicizing the issue. Taking the political corpus and the medical corpus as two extremes, we propose a language-based definition of politicization of science and measure it on a continuous scale. By building a machine learning classifier that captures subtle linguistic indicators of politicization and applying it to two years of government agencies’ Facebook posting history, we demonstrate that: 1) U.S. politicians heavily politicized COVID-19 vaccines, medical experts conveyed minimal politicization, and government agencies’ discourse was a mix of the two, yet more closely resembled medical experts;’ 2) increasing COVID-19 infection rates reduced government agencies’ politicization tendencies; 3) government agencies in Democratic-leaning states were more likely to politicize COVID-19 vaccines than those in Republican-leaning states; and 4) the degree of politicization did not significantly differ across agencies’ jurisdiction levels. We discuss the conceptualization of politicization of science, the incumbency effect, and government communication as an emerging area for political communication research.

Political Attitudes and Equity Market Reactions to Vaccine Mandate Bans
Michael Cooper et al.
University of Utah Working Paper, March 2023 


In 2021, many firms began considering and implementing vaccine mandates as a means to return workers to in-person work. In response, twelve states enacted laws banning employer COVID-19 vaccine mandates. We study equity market reactions to these bans and find a 0.64 percentage point increase in cumulative abnormal returns to affected firms over a three-day window when the bans are signed into law, compared to unaffected firms. The positive market reaction concentrates in firms in Republican-leaning counties, especially if they face a tight local labor market, and in firms with Democratic leadership but Republican workforce. Overall, our findings highlight the importance of workers’ non-monetary preferences on labor-related outcomes and suggest that regulations aligned with workers’ preferences could relieve firms from potential labor adjustment costs.

Effects of diagnosis threat on cognitive complaints after COVID-19
Daniella Winter & Yoram Braw
Health Psychology, May 2023, Pages 335–342 

Method: Recovered patients (n = 270) and controls (n = 290) reported daily cognitive failures after being randomly assigned to either a diagnosis threat (exposure to an article providing information regarding long-COVID) or a control condition.

Results: Recovered patients, but not controls, reported more cognitive failures in the diagnosis threat condition compared with the control condition. Diagnosis threat added significantly to the prediction of cognitive complaints based on relevant demographic variables and suggestibility. Diagnosis threat and suggestibility interacted (i.e., suggestible individuals were particularly vulnerable to the impact of a diagnosis threat).

Let's come to order: The influence of question order on willingness to register as an organ donor
Danielle Blazek & Jason Siegel
Social Science & Medicine, May 2023 

Method: We conducted an experiment using Amazon's Mechanical Turk (MTurk) between March and May of 2021 to investigate the influence of question order on donor registration willingness. Participants received a question regarding their willingness to register either before or after a series of questions often asked at DMVs.

Results: The placement of the donor registration question had a positive effect on registration willingness for non-registered individuals (OR = 2.01, 95% CI [1.59, 2.54]) and previously registered donors (OR = 2.57 95% CI [2.22, 2.99]).

Triangulating causality between childhood obesity and neurobehavior: Behavioral genetic and longitudinal evidence
Leonard Konstantin Kulisch et al.
Developmental Science, forthcoming 


Childhood obesity is a serious health concern that is not yet fully understood. Previous research has linked obesity with neurobehavioral factors such as behavior, cognition, and brain morphology. The causal directions of these relationships remain mostly untested. We filled this gap by using the Adolescent Brain Cognitive Development study cohort comprising 11,875 children aged 9–10. First, correlations between the age- and sex-specific 95th BMI percentile (%BMIp95) and neurobehavioral measures were cross-sectionally analyzed. Effects were then aggregated by neurobehavioral domain for causal analyses. Behavioral genetic Direction of Causation modeling was used to test the direction of each relationship. Findings were validated by longitudinal cross-lagged panel modeling. %BMIp95 correlated with impulsivity, motivation, psychopathology, eating behavior, and cognitive tests (executive functioning, language, memory, perception, working memory). Greater %BMIp95 was also associated with reduced cortical thickness in frontal and temporal brain areas but with increased thickness in parietal and occipital areas. Similar although weaker patterns emerged for cortical surface area and volume. Behavioral genetic modeling suggested causal effects of %BMIp95 on eating behavior (β = 0.26), cognition (β = 0.05), cortical thickness (β = 0.15), and cortical surface area (β = 0.07). Personality/psychopathology (β = 0.09) and eating behavior (β = 0.16) appeared to influence %BMIp95. Longitudinal evidence broadly supported these findings. Results regarding cortical volume were inconsistent. Results supported causal effects of obesity on brain functioning and morphology. The present study highlights the importance of physical health for brain development and may inform interventions aimed at preventing or reducing pediatric obesity.

Slow Traffic, Fast Food: The Effects of Time Lost on Food Store Choice 
Panka Bencsik, Lester Lusher & Rebecca Taylor
University of Chicago Working Paper, March 2023


Time scarcity is one of the strongest correlates of fast food consumption. To estimate the causal effect of time lost on food choice, we match daily store-specific foot traffic data traced via smartphones to plausibly exogenous shocks in highway traffic data in Los Angeles. We find that on days when highways are more congested, individuals are more likely to dine out and less likely to grocery shop. The effects are particularly pronounced for afternoon rush hour traffic. Our results imply a net reduction in healthy food store choice due to time lost.

Total daily energy expenditure has declined over the past three decades due to declining basal expenditure, not reduced activity expenditure
John Speakman et al.
Nature Metabolism, April 2023, Pages 579–588


Obesity is caused by a prolonged positive energy balance. Whether reduced energy expenditure stemming from reduced activity levels contributes is debated. Here we show that in both sexes, total energy expenditure (TEE) adjusted for body composition and age declined since the late 1980s, while adjusted activity energy expenditure increased over time. We use the International Atomic Energy Agency Doubly Labelled Water database on energy expenditure of adults in the United States and Europe (n = 4,799) to explore patterns in total (TEE: n = 4,799), basal (BEE: n = 1,432) and physical activity energy expenditure (n = 1,432) over time. In males, adjusted BEE decreased significantly, but in females this did not reach significance. A larger dataset of basal metabolic rate (equivalent to BEE) measurements of 9,912 adults across 163 studies spanning 100 years replicates the decline in BEE in both sexes. We conclude that increasing obesity in the United States/Europe has probably not been fuelled by reduced physical activity leading to lowered TEE. We identify here a decline in adjusted BEE as a previously unrecognized factor.

Engineering longevity -- design of a synthetic gene oscillator to slow cellular aging
Zhen Zhou et al.
Science, 28 April 2023, Pages 376-381 


Synthetic biology enables the design of gene networks to confer specific biological functions, yet it remains a challenge to rationally engineer a biological trait as complex as longevity. A naturally occurring toggle switch underlies fate decisions toward either nucleolar or mitochondrial decline during the aging of yeast cells. We rewired this endogenous toggle to engineer an autonomous genetic clock that generates sustained oscillations between the nucleolar and mitochondrial aging processes in individual cells. These oscillations increased cellular life span through the delay of the commitment to aging that resulted from either the loss of chromatin silencing or the depletion of heme. Our results establish a connection between gene network architecture and cellular longevity that could lead to rationally designed gene circuits that slow aging.


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