2 | Maria Almudena Claassen

Heuristics for Healthier Food Selection

Sun, 01 Mar 2026 00:00:00 +0000

Modern food environments challenge people’s capacity to make healthy dietary choices, lead-ing consumers to rely on heuristics—simple decision rules using limited information. Whilepolicies support this by highlighting negative nutrients on food packaging (e.g., sugar), it re-mains unclear whether such rules effectively navigate the complex nutritional trade-offs ofreal markets. We evaluate single-cue heuristics using nutrient data from over 7,600 productsand identify a small set of effective rules. By analysing nutritional profiles from hundreds ofthousands of simulated product choices, we show that a heuristic aimed at reducing energycontent also reduces sugar and saturated fat, and that heuristics targeting fibre or protein in-crease vitamin, mineral, protein, and fibre densities. Heuristics inspired by folk wisdom (e.g.,choosing raw foods or darker grains) yield broader benefits but are category-specific. Thesefindings demonstrate that such heuristics can boost healthy food choices at scale and providedata-driven guidance for nutrition policy.

Underhydration is prevalent across education levels and associated with low intake of water but notsugar-sweetened beverages - A cross-sectional study from the UK

Thu, 01 Jan 2026 00:00:00 +0000

Purpose Adequate hydration is vital for health, yet many people do not meet fluid recommendations. This study aimed to characterise the role of water and sugar-sweetened beverages in hydration across different levels of socioeconomic status (SES) in the UK.

Methods In a pre-registered cross-sectional study, participants (N = 1,112) recalled beverages consumed on the previous day and reported urine colour as an indicator of their hydration status. We analysed water intake (H1), sugar-sweetened beverage (SSB) intake (H2), and SES (education; H3) as predictors of hydration status using stepwise binomial logistic regression adjusted for health, demographic, and lifestyle covariates.

Results Forty percent of participants were classified as underhydrated. Higher water intake was associated with a greater likelihood of adequate hydration: Drinking one extra glass of water per day (250 ml) increased the odds of being adequately hydrated by about 16%. However, SSB intake was not associated with hydration unless intake from other drink sources was held constant. Having a higher versus lower level of education was not significantly associated with hydration status, although finer-grained and income-based analyses suggested modest socioeconomic differences.

Conclusion Water intake—rather than SSB intake—is the primary correlate of adequate hydration in this UK sample. Public health initiatives should emphasise the importance of water for hydration, invest in ways to make water more appealing, and promote the use of urine colour as a marker of hydration status.

The (mis-)measurement of food decisions

Sun, 01 Jun 2025 00:00:00 +0000

Humans have a fascination with quantifying behaviors. While numbers can provide intriguing insights, they can also distort public perceptions and misguide policy design. This article deconstructs the popular belief that individuals make 200 mindless food-related decisions a day, offering alternative perspectives on the conceptualization and measurement of food decisions. Specifically, we argue that existing decision-making theories offer limited guidance in defining and measuring such decisions, and advocate for more precise operationalizations. We emphasize the need for contextual understanding over simplistic numerical representations, propose a comprehensive working definition of food decisions, and consider alternative methods that may be better suited to capturing the complexity and nuance of food decisions. To conclude, we advocate for methodological pluralism in studying food decisions.

Representational shifts - Increasing motivation for bottled water through advertisements

Thu, 01 Jun 2023 00:00:00 +0000

Background Despite its numerous health benefits, consumers’ daily water consumption is below recommend levels while soft drink consumption remains high. Previous research has shown that the degree to which drinks are cognitively represented in terms of consumption and enjoyment (i.e., through simulations of consumption and reward) predicts desire and intake. Here, we examined whether simulation-enhancing advertisements that frame water in terms of consumption and reward change cognitive representations and increase motivation for a fictitious bottled water. Methods In three pre-registered online experiments (Nexp1 = 984; Nexp2 = 786; Nexp3 = 907), UK participants viewed three advertisements that either highlighted the rewarding consumption experience of water (e.g., “Refresh all your senses with this smooth, cool water”; simulation-enhancing ads), the health consequences of drinking water (e.g., “This water takes care of your health”; health-focused ads), or control ads. We assessed cognitive representations of the bottled water with a semantic feature production task, and we coded the words used as consumption and reward features or positive long-term health consequences features. We assessed motivation through ratings of the attractiveness of the water (Exp. 1 only), desire to drink it, and willingness to pay for it (WTP). Results In line with our hypotheses, participants represented the bottled water more in terms of consumption and reward after viewing simulation-enhancing advertisements, and more in terms of positive long-term health consequences after viewing health-focused advertisements. There was no direct effect of advertisement condition on motivation ratings. However, significant indirect effects showed that simulation-enhancing advertisements increased desire and WTP through the proportion of consumption and reward features, whereas health-focused advertisements increased motivation through an increase in the proportion of positive long-term health consequences features. The effects through consumption and reward were stronger. Conclusions These findings are consistent with research suggesting that the experience of immediate reward from drinking water underlies intake. Public health interventions should emphasize the enjoyment of drinking water, rather than the long-term health benefits.

Competition and moral behavior - A meta-analysis of forty-five crowd-sourced experimental designs

Mon, 01 May 2023 00:00:00 +0000

Does competition affect moral behavior? This fundamental question has been debated among leading scholars for centuries, and more recently, it has been tested in experimental studies yielding a body of rather inconclusive empirical evidence. A potential source of ambivalent empirical results on the same hypothesis is design heterogeneity—variation in true effect sizes across various reasonable experimental research protocols. To provide further evidence on whether competition affects moral behavior and to examine whether the generalizability of a single experimental study is jeopardized by design heterogeneity, we invited independent research teams to contribute experimental designs to a crowd-sourced project. In a large-scale online data collection, 18,123 experimental participants were randomly allocated to 45 randomly selected experimental designs out of 95 submitted designs. We find a small adverse effect of competition on moral behavior in a meta-analysis of the pooled data. The crowd-sourced design of our study allows for a clean identification and estimation of the variation in effect sizes above and beyond what could be expected due to sampling variance. We find substantial design heterogeneity—estimated to be about 1.6 times as large as the average standard error of effect size estimates of the 45 research designs—indicating that the informativeness and generalizability of results based on a single experimental design are limited. Drawing strong conclusions about the underlying hypotheses in the presence of substantive design heterogeneity requires moving toward much larger data collections on various experimental designs testing the same hypothesis.

Increased consumption despite fewer occasions - A longitudinal analysis of COVID-19 lockdown effects on soft drink consumption in England

Mon, 01 May 2023 00:00:00 +0000

We examined the impact of a COVID-19 lockdown in England on the frequency of consumption occasions and amount of soft drinks consumed. Beverage consumption is strongly associated with specific, often social, consumption situations (e.g., going out). We reasoned that lockdown would affect consumption behaviour because it removed typical soft drink consumption situations. Specifically, we hypothesised that soft drink consumption occasions and amount would be reduced during lockdown compared to before and after lockdown, especially in typical soft drink consumption situations. In two surveys (Dec. 2020 and May 2021) among the same participants (N = 211, N = 160; consuming soft drinks at least once/week), we assessed the frequency of soft drink and water consumption occasions before, during, and after the Nov./Dec. 2020 lockdown, across typical soft drink and water drinking situations. This presents a detailed picture of the situations in which participants drink soft drinks and water, and how this was affected by a lockdown. We also assessed the daily amount of soft drinks and water consumed in each period, and perceived habitualness of drinking soft drinks and water. As predicted, participants reported fewer occasions of drinking soft drinks during lockdown compared to before and after, especially in typical soft drink consumption situations. Unexpectedly, however, the daily amount of soft drinks consumed increased during lockdown, compared to before and after, especially among participants with stronger perceived habitualness of soft drink consumption. Exploratory analyses suggest that during lockdown, participants increased their soft drink consumption at home. Water consumption, on the other hand, was not systematically affected by the lockdown. These findings suggest that even if some typical consumption situations disappear, consumption may be hard to disrupt if the behaviour is rewarding.

I’ll have what they’re having - a descriptive social norm increases choice for vegetables in students

Mon, 01 May 2023 00:00:00 +0000

Social information, such as norms, influences behavior. Descriptive norms can be used to guide behavior toward healthier choices. Here, we examined the effect of a descriptive norm on the choice between two similar products (vegetables or fruits). Participants were exposed to a norm promoting vegetables, fruits, or no norm in a remote confederate design. A descriptive norm signaling that a greater proportion of previous participants had chosen a vegetable over a fruit basket tripled the odds of participants choosing vegetables. We found no to small effects of norms on intentions to consume fruits and vegetables or on taste expectations and experiences in a taste test. These findings suggest that descriptive norms may serve as a heuristic to guide food choices in certain choice settings involving similar options.

Grounding Motivation for Behaviour Change

Tue, 01 Mar 2022 00:00:00 +0000

Many of the key problems humans are facing today result from desires, habits, and social norms impeding behaviour change. Here, we apply a grounded cognition perspective to these phenomena, suggesting that simulating the consequences of one’s actions plays a key role in them. We first describe the grounded cognition theory of desire and motivated behaviour, and present evidence on how consumption and reward simulations underlie people’s representation of appetitive stimuli and guide motivated behaviour. Then, we discuss how the theory can be used to understand the effects of habits, social norms, and various self-regulation strategies. We suggest conceptualising behaviour change as overcoming the simulations of hedonic and social reward that favour existing habits and behaviours, and as updating situated representations of motivated behaviours in their social context. We discuss how this perspective can help us understand the challenges that people experience in initiating, preparing, and repeating new behaviours, and in high-impact decision making in the face of the status quo. In order to move beyond the socially sanctioned, habitual behaviours that currently threaten human and planetary health, we must understand what motivates them, and how this motivation can be harnessed for the greater good.

No evidence that consumption and reward words on labels increase the appeal of water

Sat, 01 May 2021 00:00:00 +0000

Many people consume too much sugar from sugar-sweetened beverages (SSBs) and would benefit from drinking water instead. Previous research has shown that taste and reward expectations play a key role in food and drink choices, and that thinking about drinks in terms of consuming and enjoying them (i.e., simulations) predicts desire and intake. Here, we examined whether labels using consumption and reward words increased the appeal of water. In three pre-registered experiments with regular consumers of SSBs (N = 1355), we presented numerous different labels of fictitious water brands with words related to the rewarding consumption experience of water (e.g., “refreshing”, “cool”), with conventional descriptions of water that emphasised its origin and purity, or with brand names only. We assessed anticipated reward of water, desire for water (Exp. 1, 2, 3), simulations of drinking water, and water attractiveness (Exp. 2 and 3). Contrary to our expectations, waters with consumption and reward-focused labels were not rated more favourably than waters with conventional labels, but both were rated higher than brand-only labels. Our findings suggest that the appeal of water cannot easily be increased by emphasising the rewarding consumption experience through language only, possibly because consumers may have a relatively fixed representation of what water tastes and feels like. Future research could test interventions that include stronger sensory information such as images to increase the appeal of water among SSB consumers.

The time is ripe - Thinking about the future reduces unhealthy eating in those with a higher BMI

Tue, 01 Sep 2020 00:00:00 +0000

Research suggests that being oriented more towards the future (than the present) is correlated with healthier eating. However, this research tends to be correlational, and thus it is unclear whether inducing people to think about their future could increase healthy eating. Therefore, we investigated whether inducing people to think about their lives in the future versus the present would influence their intake of healthy (muesli) and unhealthy (Maltesers) food. Across two experiments, the effect of thinking about the future versus the present interacted with participants’ body mass index (BMI) to influence their consumption of unhealthy food, but no reliable effects were found for the consumption of healthy food. Among individuals with a higher BMI, thinking about their lives in the future resulted in lower consumption of the unhealthy food compared to thinking about their lives in the present. However, this effect was reversed for those with a lower BMI. In Experiment 2, we found no evidence that this effect was due to reduced impulsivity (as measured by a delay discounting task and a stop-signal task). This suggests that thinking about the future can reduce unhealthy eating among heavier people.

A systematic review of psychosocial explanations for the relationship between socioeconomic status and body mass index

Tue, 01 Jan 2019 00:00:00 +0000

A negative association between socioeconomic status (SES) and levels of overweight/obesity is consistently found in high- and middle-income countries. Yet, there is little conclusive evidence about the mechanisms driving this association. In this systematic review, we discuss and compare the results of 22 studies that examine the role of psychosocial mediators in the association between SES and BMI in diverse population samples. These include factors related to resources and constraints in one’s external neighborhood, social resources, and psychological factors such as stress. The findings support theoretical models indicating that SES is related to BMI partially through environmental and psychological factors. Importantly, SES often remains a significant predictor of weight status, indicating the importance of also addressing structural antecedents in order to improve health among lower SES populations. We thoroughly discuss the quality and limitations of current study designs and mediation testing and provide recommendations for future research.

Poverty, inequality, and increased consumption of high calorie food - Experimental evidence for a causal link

Sun, 01 May 2016 00:00:00 +0000

Rising obesity represents a serious, global problem. It is now well established that obesity is associated with poverty and wealth inequality, suggesting that these factors may promote caloric intake. Whereas previous work has examined these links from an epidemiological perspective, the current paper examined them experimentally. In Study 1 we found that people experimentally induced to view themselves as poor (v. wealthy) exhibited increased calorie intake. In Study 2, participants who believed that they were poorer or wealthier than their interaction partners exhibited higher levels of anxiety compared to those in an equal partners condition; this anxiety in turn led to increased calorie consumption for people who had a strong need to belong. The findings provide causal evidence for the poverty-intake and inequality-intake links. Further, we identify social anxiety and a strong need to belong as important social psychological factors linking inequality to increased calorie intake.