The Uncontrollable Mortality Risk Hypothesis: Theoretical foundations and implications for public health.

The 'Uncontrollable Mortality Risk Hypothesis' employs a behavioural ecological model of human health behaviours to explain the presence of social gradients in health. It states that those who are more likely to die due to factors beyond their control should be less motivated to invest in preventative health behaviours. We outline the theoretical assumptions of the hypothesis and stress the importance of incorporating evolutionary perspectives into public health. We explain how measuring perceived uncontrollable mortality risk can contribute towards understanding socioeconomic disparities in preventative health behaviours. We emphasize the importance of addressing structural inequalities in risk exposure, and argue that public health interventions should consider the relationship between overall levels of mortality risk and health behaviours across domains. We suggest that measuring perceptions of uncontrollable mortality risk can capture the unanticipated health benefits of structural risk interventions, as well as help to assess the appropriateness of different intervention approaches.

The Relationship Between Perceived Uncontrollable Mortality Risk and Health Effort: Replication, Secondary Analysis, and Mini Meta-analysis.

BACKGROUND: The Uncontrollable Mortality Risk Hypothesis (UMRH) states that those who are more likely to die due to factors beyond their control should be less motivated to invest in preventative health behaviors. Greater levels of perceived uncontrollable mortality risk (PUMR) have been associated with lower health effort in previous research, but the topic remains understudied. PURPOSE: To examine the evidence for the UMRH by replicating a previous study investigating the effects of PUMR on social gradients in health effort, and conducting a mini meta-analysis of the overall relationship between PUMR and health effort. METHODS: We replicated Pepper and Nettle (2014), who reported a negative relationship between PUMR and health effort, and that the positive effect of subjective socioeconomic position on health effort was explained away by PUMR. We also compared the predictive effect of PUMR on health effort with that of dimensions from the Multidimensional Health Locus of Control scale-a well-used measure of a similar construct, which is frequently found to be associated with health behavior. Finally, we conducted a mini meta-analysis of the relationship between PUMR and health effort from the available research. RESULTS: PUMR was negatively associated with health effort, and mediated 24% of the total effect of subjective socioeconomic position on health effort, though this mediation effect was weaker than in Pepper and Nettle (2014). PUMR was shown to be a substantially stronger predictor of health effort than the relevant dimensions of the MHLC scale. Finally, our mini meta-analysis indicated a medium-sized negative relationship between PUMR and health effort. CONCLUSIONS: Our findings offer support for the role of PUMR in mediating the relationship between subjective socioeconomic position and health effort. The results highlight the importance of measuring and understanding PUMR in studying socioeconomic inequalities in health behaviors. We discuss potential areas for future research, including determining the accuracy of PUMR, investigating influential cues, examining the role of media in shaping risk perceptions, and understanding individuals' awareness of their own perceptions of mortality risk.

Previous research suggests that people who are more likely to die due to uncontrollable factors are less motivated to look after their health. This is because they are less likely to live to see the long-term benefits of a healthy lifestyle. The purpose of this study is to examine and expand upon previous research investigating the relationship between perceptions of uncontrollable mortality risk and the amount of effort people devote to their health. Our findings support past research and show that the more people feel their risk of dying is out of their control, the less effort they put into looking after their health. Our analysis suggests there is a medium-strength relationship between perceived uncontrollable mortality risk and health effort, which we argue warrants further empirical investigation. The strength of this relationship emphasizes the importance of improving the safety of people's living environments and highlights the positive impact that this can have on health behaviors.

Individual characteristics associated with perceptions of control over mortality risk and determinants of health effort.

People who believe they have greater control over health and longevity are typically more likely to invest in their long-term health. Investigating individual differences in perceived control over risk and exploring different determinants of health effort may help to tailor health promotion programs to more effectively encourage healthy behaviors. From a sample of 1500 adults, we measured perceived control over 20 causes of death, overall perceived uncontrollable mortality risk (PUMR), state-level optimism, self-reported health effort, and the accuracy of estimations of avoidable deaths. We found individual differences in perceptions of control over specific causes of death based on age, gender, and income. PUMR was predicted by socioeconomic variables expected to influence exposure to risk and resource availability. Higher levels of PUMR, not perceptions of control over specific causes of death, predicted self-reported health effort. The strength of relationship between PUMR and lower health effort was not moderated by state-level optimism. Age and education both positively predicted greater accuracy in assessing the prevalence of avoidable deaths. We suggest that PUMR may capture people's "general sense" of mortality risk, influenced by both exposure to hazards and the availability of resources to avoid threats. Conversely, perceived control over specific risks may involve more deliberate, considered appraisals of risk. This general sense of risk is thought to play a more notable role in determining health behaviors than specific assessments of control over risk. Further study is needed to investigate the degree to which PUMR accurately reflects objective measures of individual risk.

No effect of hunger on attentional capture by food cues: Two replication studies.

Food cues potently capture human attention, and it has been suggested that hunger increases their propensity to do so. However, the evidence for such hunger-related attentional biases is weak. We focus on one recent study that did show significantly greater attentional capture by food cues when participants were hungry, using an Emotional Blink of Attention (EBA) task [Piech, Pastorino, & Zald, 2010. Appetite, 54, 579-582]. We conducted online (N = 29) and in-person (N = 28) replications of this study with British participants and a Bayesian analytical approach. For the EBA task, participants tried to identify a rotated target image in a Rapid Serial Visual Presentation (RSVP). Targets were preceded by "neutral", "romantic", or "food" distractor images. Participants completed the task twice, 6-11 days apart, once hungry (overnight plus 6h fast) and once sated (after a self-selected lunch in the preceding 1h). We predicted that food images would create a greater attentional blink when participants were hungry than when they were sated, but romantic and neutral images would not. We found no evidence that hunger increased attentional capture by food cues, despite our experiments passing manipulation and quality assurance checks. Our sample and stimuli differed from the study we were replicating in several ways, but we were unable to identify any specific factor responsible for the difference in results. The original finding may not be generalisable. The EBA is more sensitive to the physical distinctiveness of distractors from filler and target images than their emotional valence, undermining the sensitivity of the EBA task for picking up subtle changes in motivational state. Moreover, hunger-related attentional bias shifts may not be substantial over the intensities and durations of hunger typically induced in laboratory experiments.

Food insecurity as a cause of adiposity: evolutionary and mechanistic hypotheses.

Food insecurity (FI) is associated with obesity among women in high-income countries. This seemingly paradoxical association can be explained by the insurance hypothesis, which states that humans possess evolved mechanisms that increase fat storage to buffer against energy shortfall when access to food is unpredictable. The evolutionary logic underlying the insurance hypothesis is well established and experiments on animals confirm that exposure to unpredictable food causes weight gain, but the mechanisms involved are less clear. Drawing on data from humans and other vertebrates, we review a suite of behavioural and physiological mechanisms that could increase fat storage under FI. FI causes short-term hyperphagia, but evidence that it is associated with increased total energy intake is lacking. Experiments on animals suggest that unpredictable food causes increases in retained metabolizable energy and reductions in energy expenditure sufficient to fuel weight gain in the absence of increased food intake. Reducing energy expenditure by diverting energy from somatic maintenance into fat stores should improve short-term survival under FI, but the trade-offs potentially include increased disease risk and accelerated ageing. We conclude that exposure to FI plausibly causes increased adiposity, poor health and shorter lifespan. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part II)'.

Perceptions of control over different causes of death and the accuracy of risk estimations.

Background: A large number of deaths could be avoided by improving health behaviours. The degree to which people invest in their long-term health is influenced by how much they believe they can control their risk of death. Identifying causes of death believed to be uncontrollable, but likely to occur, may provide actionable targets for health interventions to increase control beliefs and encourage healthier behaviours. Method: We recruited a nationally representative online sample of 1500 participants in the UK. We assessed perceived control, perceived personal likelihood of death, certainty of risk estimation, and perceived knowledge for 20 causes of death. We also measured overall perceived uncontrollable mortality risk (PUMR) and perceived prevalence for each of the Office for National Statistics' categories of avoidable death. Findings: Risk of death due to cancer was considered highly likely to occur but largely beyond individual control. Cardiovascular disease was considered moderately controllable and a likely cause of death. Drugs and alcohol were perceived as risks both high in control and low in likelihood of death. However, perceptions of control over specific causes of death were found not to predict overall PUMR, with the exception of cardiovascular disease. Finally, our sample substantially overestimated the prevalence of drug and alcohol-related deaths in the UK. Conclusions: We suggest that more can be done by public health communicators to emphasise the lifestyle and behavioural changes that individuals can make to reduce their general cancer risk. More work is needed to understand the barriers to engaging with preventative behaviours and maintaining a healthy heart. Finally, we call for greater journalistic responsibility when reporting health risks to the public. Supplementary Information: The online version contains supplementary material available at 10.1007/s10389-023-01910-8.

COVID-19: the relationship between perceptions of risk and behaviours during lockdown.

Aim: Understanding COVID-19 risk perceptions and their impact on behaviour can improve the effectiveness of public health strategies. Prior evidence suggests that, when people perceive uncontrollable risks to their health, they are less likely to engage in healthful behaviour. This article aims to understand the extent to which COVID-19 is perceived as an uncontrollable risk, and to assess whether this perceived risk is associated with health behaviour. Subject and methods: We surveyed a nationally representative sample of 496 participants during the first UK lockdown. We assessed perceptions of COVID-19-related risk, self-reported adherence to infection control measures recommended by the UK Government, and general health behaviours. We predicted that increased perceived extrinsic mortality risk (the portion of mortality risk perceived to be uncontrollable) would disincentivise healthy behaviour. Results: Perceived threat to life was the most consistent predictor of reported adherence to infection control measures. Perceived extrinsic mortality risk was found to have increased due to the pandemic, and was associated with lower reported adherence to Government advice on diet, physical activity, and smoking. Conclusions: Our findings suggest that health messages that highlight threat to life may be effective in increasing adherence to infection control, but may also lead to a reduction in health-promoting behaviours. We suggest that messages that highlight threat to life should be accompanied by statements of efficacy. Further, messages evoking feelings of concern for others may be effective in promoting compliance with anti-infection measures, without the potential for the unwelcome side-effect of discouraging healthy behaviour. Supplementary Information: The online version contains supplementary material available at 10.1007/s10389-021-01543-9.

A qualitative study of perceptions of control over potential causes of death and the sources of information that inform perceptions of risk.

Background: Investigating perceptions of control over mortality risk may be fundamental to understanding health behaviours and tackling socioeconomic gradients in health. Few studies have explored perceptions of control over different causes of death and there is a lack of qualitative risk research. Our aim was to examine participants' perceptions of control over potential causes of death and the sources that inform perceptions of risk. Method: We conducted semi-structured interviews with 24 participants (14 female and 10 male) and conducted a template analysis to analyse the transcripts. Findings: We identified six themes to represent participants' perceptions of control over potential mortality risks and the sources that inform these perceptions: Health-Related Mortality Risks, External Causes of Risk, Finding Balance, Family Medical History, Online Sources of Risk and Health-Related Information, and Health Misinformation. Dying from heart disease was broadly reported as being a controllable risk, whereas cancer was mostly discussed as uncontrollable. Gender-specific cancers were perceived as posing a significant risk to life, however controlling this risk was discussed in terms of screening and treatment, not prevention. Family medical history was discussed as an informative source for longevity predictions, but less so for specific causes of death. Most risk information is retrieved from 'Dr Google', though trusted sources, such as NHS websites, are used for validation. Health misinformation online was seen as a problem experienced by other people, rather than the individual. Conclusions: Causal pathways between behaviours and specific cancers may not be obvious to individuals. Messages emphasising the broader links between diet, alcohol and general cancer risk may highlight the controllability of cancer risk through improved health behaviours. Furthermore, given the rise in health misinformation, and the belief that it is other people not ourselves that are typically susceptible to believing misinformation online, further attempts are needed to combat this growing 'infodemic'.

Food insecurity and patterns of dietary intake in a sample of UK adults.

The aim of this study was to identify the dietary intake correlates of food insecurity (FI) in UK adults. We recruited groups of low-income participants who were classified as food insecure (n 196) or food secure (n 198). Participants completed up to five 24 h dietary recalls. There was no difference in total energy intake by FI status (ßFI = -0·06, 95 % CI - 0·25, 0·13). Food insecure participants consumed a less diverse diet, as evidenced by fewer distinct foods per meal (ßFI = -0·27, 95 % CI - 0·47, -0·07), and had more variable time gaps between meals (ßFI = 0·21, 95 % CI 0·01, 0·41). These associations corresponded closely to those found in a recent US study using similar measures, suggesting that the dietary intake signature of FI generalises across populations. The findings suggest that the consequences of FI for weight gain and health are not due to increased energy intake. We suggest that there may be important health and metabolic effects of temporal irregularity in dietary intake, which appears to be an important component of FI.

Smoking does not accelerate leucocyte telomere attrition: a meta-analysis of 18 longitudinal cohorts.

Smoking is associated with shorter leucocyte telomere length (LTL), a biomarker of increased morbidity and reduced longevity. This association is widely interpreted as evidence that smoking causes accelerated LTL attrition in adulthood, but the evidence for this is inconsistent. We analysed the association between smoking and LTL dynamics in 18 longitudinal cohorts. The dataset included data from 12 579 adults (4678 current smokers and 7901 non-smokers) over a mean follow-up interval of 8.6 years. Meta-analysis confirmed a cross-sectional difference in LTL between smokers and non-smokers, with mean LTL 84.61 bp shorter in smokers (95% CI: 22.62 to 146.61). However, LTL attrition was only 0.51 bp yr-1 faster in smokers than in non-smokers (95% CI: -2.09 to 1.08), a difference that equates to only 1.32% of the estimated age-related loss of 38.33 bp yr-1. Assuming a linear effect of smoking, 167 years of smoking would be required to generate the observed cross-sectional difference in LTL. Therefore, the difference in LTL between smokers and non-smokers is extremely unlikely to be explained by a linear, causal effect of smoking. Selective adoption, whereby individuals with short telomeres are more likely to start smoking, needs to be considered as a more plausible explanation for the observed pattern of telomere dynamics.

Cuing both positive and negative episodic foresight reduces delay discounting but does not affect risk-taking.

Humans frequently create mental models of the future, allowing outcomes to be inferred in advance of their occurrence. Recent evidence suggests that imagining positive future events reduces delay discounting (the devaluation of reward with time until its receipt), while imagining negative future events may increase it. Here, using a sample of 297 participants, we experimentally assess the effects of cued episodic simulation of positive and negative future scenarios on decision-making in the context of both delay discounting (monetary choice questionnaire) and risk-taking (balloon-analogue risk task). Participants discounted the future less when cued to imagine positive and negative future scenarios than they did when cued to engage in control neutral imagery. There were no effects of experimental condition on risk-taking. Thus, although these results replicate previous findings suggesting episodic future simulation can reduce delay discounting, they indicate that this effect is not dependent on the valence of the thoughts, and does not generalise to all other forms of "impulsive" decision-making. We discuss various interpretations of these results, and suggest avenues for further research on the role of prospection in decision-making.

Telomeres as integrative markers of exposure to stress and adversity: a systematic review and meta-analysis.

Telomeres have been proposed as a biomarker that integrates the impacts of different kinds of stress and adversity into a common currency. There has as yet been no overall comparison of how different classes of exposure associate with telomeres. We present a meta-analysis of the literature relating telomere measures to stresses and adversities in humans. The analysed dataset contained 543 associations from 138 studies involving 402 116 people. Overall, there was a weak association between telomere variables and exposures (greater adversity, shorter telomeres: r = -0.15, 95% CI -0.18 to -0.11). This was not driven by any one type of exposure, because significant associations were found separately for physical diseases, environmental hazards, nutrition, psychiatric illness, smoking, physical activity, psychosocial and socioeconomic exposures. Methodological features of the studies did not explain any substantial proportion of the heterogeneity in association strength. There was, however, evidence consistent with publication bias, with unexpectedly strong negative associations reported by studies with small samples. Restricting analysis to sample sizes greater than 100 attenuated the overall association substantially (r = -0.09, 95% CI -0.13 to -0.05). Most studies were underpowered to detect the typical association magnitude. The literature is dominated by cross-sectional and correlational studies which makes causal interpretation problematic.

The relationships between exercise and affective states: a naturalistic, longitudinal study of recreational runners.

BACKGROUND: Although people generally feel more positive and more energetic in the aftermath of exercise than before, longitudinal research on how exercise relates to within-person fluctuations in affect over the course of everyday life is still relatively limited. One constraint on doing such research is the need to provide participants with accelerometers to objectively record their exercise, and pagers to capture affective reports. AIMS: We aimed to develop a methodology for studying affect and exercise using only technology that participants already possess, namely GPS running watches and smartphones. Using this methodology, we aimed to characterize within-individual fluctuations in affective valence and arousal in relation to bouts of exercise, and explore possible moderators of these fluctuations. METHODS: We recruited a sample of 38 recreational runners. Participants provided daily affective reports for six weeks using their smartphones. Information on their runs was harvested from their own GPS devices via an online platform for athletes. RESULTS: Average valence and arousal were higher on days when the person had run than on the next day, and higher the day after a run than on the days after that. Over the course of the day of a run, valence and arousal declined significantly as the time since the run increased. Physically fitter participants had more positive valence overall, and this was particularly true when they had not run recently. There was some evidence of higher-dose (i.e., longer and faster) runs being associated with lower arousal on the next and subsequent days. Gender did not moderate associations between running and valence or arousal. DISCUSSION: Our study demonstrated the potential for studying the associations between affect and exercise in a way that is precise, undemanding for participants, and convenient for researchers, using technologies that participants already own and use.

The influence of mortality and socioeconomic status on risk and delayed rewards: a replication with British participants.

Here, we report three attempts to replicate a finding from an influential psychological study (Griskevicius et al., 2011b). The original study found interactions between childhood SES and experimental mortality-priming condition in predicting risk acceptance and delay discounting outcomes. The original study used US student samples. We used British university students (replication 1) and British online samples (replications 2 and 3) with a modified version of the original priming material, which was tailored to make it more credible to a British audience. We did not replicate the interaction between childhood SES and mortality-priming condition in any of our three experiments. The only consistent trend of note was an interaction between sex and priming condition for delay discounting. We note that psychological priming effects are considered fragile and often fail to replicate. Our failure to replicate the original finding could be due to demographic differences in study participants, alterations made to the prime, or other study limitations. However, it is also possible that the previously reported interaction is not a robust or generalizable finding.

The behavioural constellation of deprivation: Causes and consequences.

Socioeconomic differences in behaviour are pervasive and well documented, but their causes are not yet well understood. Here, we make the case that a cluster of behaviours is associated with lower socioeconomic status (SES), which we call "the behavioural constellation of deprivation." We propose that the relatively limited control associated with lower SES curtails the extent to which people can expect to realise deferred rewards, leading to more present-oriented behaviour in a range of domains. We illustrate this idea using the specific factor of extrinsic mortality risk, an important factor in evolutionary theoretical models. We emphasise the idea that the present-oriented behaviours of the constellation are a contextually appropriate response to structural and ecological factors rather than a pathology or a failure of willpower. We highlight some principles from evolutionary theoretical models that can deepen our understanding of how socioeconomic inequalities can become amplified and embedded. These principles are that (1) small initial disparities can lead to larger eventual inequalities, (2) feedback loops can embed early-life circumstances, (3) constraints can breed further constraints, and (4) feedback loops can operate over generations. We discuss some of the mechanisms by which SES may influence behaviour. We then review how the contextually appropriate response perspective that we have outlined fits with other findings about control and temporal discounting. Finally, we discuss the implications of this interpretation for research and policy.

Using foresight to prioritise the present.

Planning for the future may encourage apparently "impulsive" behaviour when the future is anticipated to be bleak. Thus, a seeming failure of self-control in reactive violence could be caused not by a disinclination to plan ahead, but by virtue of this ability. Furthermore, we point to empirical and theoretical shortcomings in the authors' case, such as a failure to distinguish proximate and ultimate explanations.

Strengths, altered investment, risk management, and other elaborations on the behavioural constellation of deprivation.

We are grateful to have received so many insightful commentaries from interested colleagues regarding our proposed behavioural constellation of deprivation (BCD) and our thoughts on its causes and consequences. In this response article, we offer some clarifications regarding our perspective and tackle some common misperceptions, including, for example, assumptions that the BCD is adaptive and that it should include all behaviours that vary with socioeconomic status. We then welcome some excellent proposals for extensions and modifications of our ideas, such as the conceptualisation of the BCD as a risk-management strategy and the calls for a greater focus on strengths and differential investment rather than deficits and disinvestment. Finally, we highlight some insightful explorations of the implications of our ideas for ethics, policy, and practice.

The evolved psychological mechanisms of fertility motivation: hunting for causation in a sea of correlation.

Cultural, ecological, familial and physiological factors consistently influence fertility behaviours, however, the proximate psychological mechanisms underlying fertility decisions in humans are poorly understood. Understanding the psychological mechanisms underlying human fertility may illuminate the final processes by which some of these known predictors have their influence. To date, research into the psychological mechanisms underlying fertility has been fragmented. Aspects of reproductive psychology have been examined by researchers in a range of fields, but the findings have not been systematically integrated in one review. We provide such a review, examining current theories and research on psychological mechanisms of fertility. We examine the methods and populations used in the research, as well as the disciplines and theoretical perspectives from which the work has come. Much of the work that has been done to date is methodologically limited to examining correlations between ecological, social and economic factors and fertility. We propose, and support with examples, the use of experimental methods to differentiate causal factors from correlates. We also discuss weaknesses in the experimental research, including limited work with non-WEIRD (western, educated, industrialized, rich and democratic) populations.

Out of control mortality matters: the effect of perceived uncontrollable mortality risk on a health-related decision.

Prior evidence from the public health literature suggests that both control beliefs and perceived threats to life are important for health behaviour. Our previously presented theoretical model generated the more specific hypothesis that uncontrollable, but not controllable, personal mortality risk should alter the payoff from investment in health protection behaviours. We carried out three experiments to test whether altering the perceived controllability of mortality risk would affect a health-related decision. Experiment 1 demonstrated that a mortality prime could be used to alter a health-related decision: the choice between a healthier food reward (fruit) and an unhealthy alternative (chocolate). Experiment 2 demonstrated that it is the controllability of the mortality risk being primed that generates the effect, rather than mortality risk per se. Experiment 3 showed that the effect could be seen in a surreptitious experiment that was not explicitly health related. Our results suggest that perceptions about the controllability of mortality risk may be an important factor in people's health-related decisions. Thus, techniques for adjusting perceptions about mortality risk could be important tools for use in health interventions. More importantly, tackling those sources of mortality that people perceive to be uncontrollable could have a dual purpose: making neighbourhoods and workplaces safer would have the primary benefit of reducing uncontrollable mortality risk, which could lead to a secondary benefit from improved health behaviours.

Perceived extrinsic mortality risk and reported effort in looking after health: testing a behavioral ecological prediction.

Socioeconomic gradients in health behavior are pervasive and well documented. Yet, there is little consensus on their causes. Behavioral ecological theory predicts that, if people of lower socioeconomic position (SEP) perceive greater personal extrinsic mortality risk than those of higher SEP, they should disinvest in their future health. We surveyed North American adults for reported effort in looking after health, perceived extrinsic and intrinsic mortality risks, and measures of SEP. We examined the relationships between these variables and found that lower subjective SEP predicted lower reported health effort. Lower subjective SEP was also associated with higher perceived extrinsic mortality risk, which in turn predicted lower reported health effort. The effect of subjective SEP on reported health effort was completely mediated by perceived extrinsic mortality risk. Our findings indicate that perceived extrinsic mortality risk may be a key factor underlying SEP gradients in motivation to invest in future health.