Delay discounting and household food purchasing decisions: The SHoPPER study

Delay Discounting and BMI in Hypertensives: Serial Mediations of Self-Efficacy, Physical Activity and Sedentary Behavior

Objective

Our study aimed to examine the association between delay discounting (DD) and body mass index (BMI) in individuals with hypertension. Additionally, we sought to explore and compare the potential mediating effects of self-efficacy, physical activity and sedentary behavior in this association.

Methods

A cross-sectional survey was conducted in two cities in the Jiangsu province of China, specifically Nanjing and Yangzhou, from March to June 2023. A total of 972 hypertensive patients completed the questionnaire (M age = 64.7 years, SD age = 8.2 years, 54.2% female). Participants engaged in a money choice experiment on computers, provided their height and weight, and completed the International Physical Activity Questionnaire-Short Form (IPAQ-SF) and General Self-Efficacy Scale (GSES). The experimental program was generated using the programming software E-Prime version 2.0. Multiple hierarchical regression analysis was conducted to identify potential covariates. Two serial mediation models were conducted using PROCESS macro 4.1 in SPSS 27.0. Physical activity and sedentary behavior were designated as M2 to investigate and contrast their respective mediating effects in the association between delay discounting and body mass index.

Results

Self-efficacy, physical activity, and sedentary behavior served as mediators in the relationship between delay discounting and BMI. Self-efficacy accounted for 14.9% and 14.3% of the total effect in Models 1 and 2, respectively, while physical activity and sedentary behavior each accounted for 14.9% and 9.5% of the total effect, respectively. The serial mediation effects of self-efficacy and physical activity, as well as self-efficacy and sedentary behavior, were significant (B = 0.01, 95% CI [0.01, 0.02]; B = 0.01, 95% CI [0.002, 0.01]), collectively contributing 2.1% and 2.4% of the total effect. Sedentary behavior played a smaller mediating role compared to physical activity in this association.

Conclusion

The results indicated that self-efficacy, physical activity and sedentary behavior could act as mediators in the association between delay discounting and BMI, thus potentially mitigating the risk of obesity in hypertensive individuals.

Relationship Between Delay Discounting and Clinical Diabetes Outcomes: A Systematic Review

OBJECTIVE

To evaluate the evidence on the relationship between delay discounting and clinical diabetes outcomes, identify current measures, and recommend areas for future work.

METHODS

A reproducible search using OVID Medline, PsycINFO, PubMed, Science Direct, and Scopus was conducted. Articles published from database creation up to March 2024 were searched. Medical Subject Heading (MeSH) terms and keywords representing delay discounting and diabetes were used. Outcomes included hemoglobin A1c (HbA1c), LDL, body mass index (BMI), blood pressure, quality of life (QOL), psychosocial factors, self-care behaviors, and diabetes complications.

RESULTS

A total of 15 articles met the inclusion criteria and were included for final synthesis. Overall, 14 studies included in this review found a significant relationship between delay discounting and diabetes-related outcomes, such that higher delay discounting is significantly related to worse diabetes outcomes for HbA1c, self-care behaviors, BMI, stress, and quality of life across self-reported measures of delay discounting and delay discounting tasks.

CONCLUSIONS

Evidence supports the relationship between delay discounting and diabetes-related outcomes and self-care behaviors across measures of delay discounting and type of diabetes. To understand delay discounting as a mechanism driving diabetes outcomes and to develop targeted interventions, additional work using a multidisciplinary approach is needed to validate the construct, identify pathways, and refine intervention approaches that can be tested to improve population health.

Positive autobiographical memory recall does not influence temporal discounting: an internal meta-analysis of experimental studies

People tend to discount the value of future rewards as the delay to receiving them increases. This phenomenon, known as temporal discounting, may underlie many impulsive behaviors, such as drug abuse and overeating. Given the potential role of temporal discounting in maladaptive behaviors, many efforts have been made to find experimental manipulations that reduce temporal discounting. One class of manipulations that has held some promise involves recalling positive autobiographical memories prior to making intertemporal choices. Just as imagining positive future events has been shown to reduce temporal discounting, a few studies have shown that recalling positive past events reduces temporal discounting, especially if memory retrieval evokes positive affective states, such as gratitude and nostalgia. However, we failed to replicate these findings. Here we present an internal meta-analysis combining data from 14 studies (n = 758) that involved within-subjects positive memory recall-based manipulations. In each study, temporal discounting was assessed using a monetary intertemporal choice task. The average effect size was not significantly different from zero. This finding helps elucidate the neurocognitive mechanisms of temporal discounting; whereas engaging the episodic memory system to imagine future events might promote more patience, engaging the episodic memory system to imagine past events does not.

Recent Experience Affects Delay Discounting: Evidence across Temporal Framing, Signs, and Magnitudes

Delay discounting, the decrease in outcome value as a function of delay to receipt, is an extensive area of research. How delays are framed (i.e., temporal framing), as well as the sign and magnitude of an outcome, produce important effects on the degree to which outcomes are discounted. Here, we examined how recent experience (i.e., order of presentation) modifies these well-known findings. Experiment 1 examined the effects of temporal framing across gains and losses. Regardless of outcome sign, the order of task presentation affected the effect of temporal framing. In particular, when typical delay frames (e.g., 1 week) preceded delays framed as actual dates (e.g., February 15), discounting was less in the date-framed task. However, when dates were followed by the delay frame, there was no difference in the degree of discounting. The experience of date-framed delays persisted or carried over to the delay-framed task. Experiment 2 examined recent experience and the magnitude effect. In particular, $10 and $100 were discounted similarly between-subjects when it was the first task completed. However, once participants completed the second magnitude task, the magnitude effect was present both within-subjects and across subjects. Furthermore, $10 was discounted more steeply when it followed $100, and $100 was discounted less steeply when it followed $10. The impact of recent experience on delay discounting has important implications for understanding mechanisms that may contribute to delay discounting. Recent experience should be considered when designing delay discounting experiments as well as when implementing interventions to reduce steep delay discounting.

Health Prompts Affect Consideration of Health but Not Intertemporal Preferences While Promoting Healthier Food Choices

Diet-related diseases impact populations across the globe. While intertemporal preferences-a fundamental preference for the distribution of benefits across time-have been used to explain low-quality food choices, the recent literature proposes another cause: inattention to the future implications (or opportunity costs) of the options faced. Food choices tend to become habitual to conserve cognitive resources, rather than carefully modeling future health impacts. Both low discount rates for future benefits and attention to future health impacts predict healthier decisions. While intertemporal preferences are stable, attention may provide an opportunity to intervene in the decision process to promote healthier decisions. In this study, we test the impact of a simple message that highlights health during food choice on the healthiness of the foods chosen and on health consideration and intertemporal preferences. Our results show that actively considering health outcomes and lower discount rates lead to healthier food choices. We find that messaging increases the consideration of health outcomes during food choice but does not affect intertemporal preferences, suggesting that simple prompts may be an effective way to promote decisions balancing short- and long-term benefits by drawing attention to the overlooked opportunity costs of choices.

Tunneling, cognitive load and time orientation and their relations with dietary behavior of people experiencing financial scarcity - an AI-assisted scoping review elaborating on scarcity theory

BACKGROUND

The concept of a financial scarcity mindset has raised much attention as an explanation for poor decision-making and dysfunctional behavior. It has been suggested that financial scarcity could also impair dietary behavior, through a decline in self-control. Underlying cognitive mechanisms of tunneling (directing attention to financial issues and neglecting other demands), cognitive load (a tax on mental bandwidth interfering with executive functioning) and time orientation (a shift towards a present time horizon, versus a future time horizon) may explain the association between financial scarcity and self-control related dietary behavior. The current scoping review gathers recent evidence on how these mechanisms affect dietary behavior of people experiencing financial scarcity. It builds on a theoretical framework based on insights from behavioral economics and health psychology.

METHODS

A literature search was executed in six online databases, which resulted in 9.975 papers. Search terms were tunneling, cognitive load and time orientation, financial scarcity, and dietary behavior. Screening was performed with ASReview, an AI-ranking tool. In total, 14 papers were included in the scoping review. We used PRISMA-ScR guidelines for reporting.

RESULTS

Limited evidence indicates that a scarcity mindset could increase tunneling, through attentional narrowing on costs of food, which then directly impacts dietary behavior. A scarcity mindset involves experiencing financial stress, which can be understood as cognitive load. Cognitive load decreases attentional capacity, which could impair self-control in dietary choices. Financial scarcity is related to a present time orientation, which affects dietary choices by shifting priorities and decreasing motivation for healthy dietary behavior.

CONCLUSIONS

A scarcity mindset affects dietary behavior in different ways. Tunneling and a shift in time orientation are indicative of an attentional redirection, which can be seen as more adaptive to the situation. These may be processes indirectly affecting self-control capacity. Cognitive load could decrease self-control capacity needed for healthy dietary behavior because it consumes mental bandwidth. How a changing time orientation when experiencing financial scarcity relates to motivation for self-control in dietary behavior is a promising theme for further inquiry.

Relationship between delay discounting, delay aversion and psychosocial domains of diabetes care

PURPOSE

Delay discounting and aversion are important areas for diabetes management; however, little has been done to understand the relationship with psychosocial outcomes among adults with type 2 diabetes.

METHODS

This study used data from 365 adults with type 2 diabetes to evaluate relationships between delay discounting and aversion and psychosocial outcomes. Delay discounting and aversion were measured with the validated Quick Delay Questionnaire. Psychosocial outcomes included depression, measured by the PHQ, anxiety by the GAD scale, perceived stress by the PSS, and social support by the Duke Social Support and Stress Scale. Multiple linear regression was used to assess the relationship between delay discounting and aversion on psychological health and social support controlling for relevant covariates.

RESULTS

Mean age of the sample was 61.8 years, 54.5 % were NHB, 41.8 % NHW, and 3.7 % Hispanic/Other. After adjusting for covariates, delay aversion was significantly associated with depression (beta = 0.35; p < 0.001), anxiety (beta = 0.52; p < 0.001), perceived stress (beta = 0.22; p < 0.001), and lower family support (beta = -0.62; p < 0.05). Delay discounting was significantly associated with depression (beta = 0.32; p < 0.001), anxiety (beta = 0.46; p < 0.001), and perceived stress (beta = 0.26; p < 0.001).

LIMITATIONS

This data is cross-sectional, future work should examine the longitudinal relationship while also including additional psychosocial outcomes.

CONCLUSIONS

Delay discounting and aversion are significantly associated with poor psychosocial outcomes, including lower social support. As the body of evidence grows, additional research is needed to better understand the construct, mechanisms, and the impact of choice settings to better inform intervention development.

COVID-19-related financial scarcity is associated with greater delay discounting but not probability discounting

Prior studies suggest that scarcity increases delay discounting (devaluation of delayed outcomes) and disturbs other decision-making processes. Evidence on the effect of COVID-19 on delay discounting is mixed. Also, no study has examined the effect of COVID-19-related scarcity on probability discounting (devaluation of probabilistic outcomes). The goal of the study was to examine cross-sectional associations between financial impact during the COVID-19 pandemic, delay discounting, and probability discounting. During April 2020, 1012 participants with low income were recruited on Amazon Mechanical Turk and completed measures of delay and probability discounting, perceived COVID-19-related financial impacts, and food security. Regression analyses indicate that compared to those with no COVID-19-related financial impacts, those with severe COVID-19-related financial impacts had greater delay discounting of money and greater delay discounting of a grocery gift card. Also, greater food insecurity in the past month was associated with greater delay discounting of a grocery gift card but not delay discounting of money. Perceived COVID-19 related financial impact was not associated with probability discounting. Combined with laboratory experiments, this study provides additional support for the idea that feelings of scarcity may increase delay discounting. However, as this study was observational, no assumptions of causality should be made about the specific effect of COVID-19 on delay discounting.

Valuing the future at different temporal points: The role of time framing on discounting

The rate of delay discounting exhibited by individuals has been experimentally altered by manipulating the way in which time is described, a specific application of the framing effect. Previous research suggests that using specific dates to describe delays tends to lower temporal discounting and change the shape of the discounting function. The main purpose of this study was to assess the influence of framing on discounting in different temporal contexts. Participants chose between hypothetical monetary gains (gains group), or between hypothetical monetary losses (losses group). Each group completed eight discounting tasks over two sessions (two choice tasks [SmallNow/SmallSoon] by two time frames [dates/calendar units] by two magnitudes. The results indicate that Mazur's model adequately described the observed discounting functions in most conditions. However, the decrease in discounting rate when both consequences were delayed only occurred when calendar units (but not dates) were used for both gains and losses. These findings suggest that framing affects the influence of a shared delay instead of changing the shape of the discounting function. Our results support the idea that time influences behavior similarly in humans and nonhumans when they choose between two delayed consequences.

Rationale and Design of the Groceries for Black Residents of Boston to Stop Hypertension Among Adults Without Treated Hypertension (GoFresh) Trial

BACKGROUND

Poor diet quality significantly contributes to hypertension disparities affecting Black adults. While the Dietary Approaches to Stop Hypertension (DASH) eating pattern lowers blood pressure (BP), access to DASH-patterned groceries is a major barrier for residents of urban food deserts.

METHODS

The Groceries for Black Residents of Boston to Stop Hypertension among Adults without Treated Hypertension (GoFresh) study is one of five projects in the RESTORE Network, an AHA-funded initiative focused on hypertension prevention. GoFresh is testing whether online, dietitian-assisted, home-delivered, DASH-patterned groceries lowers BP among Black adults with elevated BP. This individual-level, parallel-arm trial will enroll up to 176 Black adults with SBP (systolic blood pressure) between 120 and <150 mm Hg residing in Boston-area communities with reduced grocery store access. Following randomization, half of the participants will be assigned to weekly sessions with a dietitian who will assist participants in ordering DASH-patterned groceries online for home delivery; the remainder will receive a $500 monthly stipend. Both interventions will last 3 months, followed by a 9-month maintenance phase.

RESULTS

The primary outcome is the difference in SBP after 3 months. Secondary outcomes include a change in 24-hour ambulatory BP, body mass index, 24-hour urine sodium and potassium, hemoglobin A1C, lipids, fruit and vegetable intake, and saturated fat intake. Qualitative interviews with 45 participants 6 months after baseline assessments will determine barriers and facilitators to long-term maintenance of DASH-patterned grocery shopping.

DISCUSSION

Findings from this study will inform ongoing work on scalable interventions to prevent hypertension among Black adults with implications for public and healthcare-based food supplementation programs.

TRIAL REGISTRATION

NCT05121337. Registered on 16 November 2021, at ClinicalTrials.gov: https://clinicaltrials.gov/ct2/show/NCT05121337.

Information, ingestion, and impulsivity: The impact of technology-enabled healthy food labels on online grocery shopping in impulsive and non-impulsive consumers

Introduction

Unhealthy food consumption is a problem for society, companies, and consumers. This study aims to contribute to knowledge regarding such issues by investigating how technology-enabled healthy food labels can impact food choice in an online grocery store context. We conceptualized unhealthy and healthy food choice as a matter of impulsivity problems. Three technology-enabled healthy food labels were derived based on variables that might impact self-control, and their influence on food choice was investigated.

Methods

The empirical study consisted of three parts. In the first part, participants’ impulsivity was measured using an adjusting delay task. Part two investigated the effects of self-monitoring, pre-commitment, and social comparison-based technology-enabled healthy food labels on food choice in a hypothetical online grocery shopping setting using a choice-based conjoint experiment. Lastly, in the third part, three where demographical questions were asked.

Results

The results (n = 405) show that self-monitoring, pre-commitment, and social comparison-based technology-enabled healthy food labels had the most to least impact on food choice in that order. Furthermore, the results indicate that self-monitoring and pre-commitment labels had more impact on the choice for impulsive compared to non-impulsive participants. Similarly, the results indicate that social comparison had more impact on choice for non-impulsive participants. These findings suggest that self-monitoring of previous healthy food choices might be more effective than pre-commitment based on discounts for healthy food products. However, these differences were minor.

Discussion

This finding has managerial implications as grocery stores might increase their revenue by introducing self-monitoring labels in an online grocery shopping setting. Future research should investigate these technology-enabled healthy food labels in natural food purchase settings.

Putting prospection into practice: Methodological considerations in the use of episodic future thinking to reduce delay discounting and maladaptive health behaviors

In recent years, episodic future thinking (EFT) has emerged as a promising behavioral intervention to reduce delay discounting or maladaptive health behaviors; however, considerable methodological heterogeneity in methods for eliciting engagement in EFT has been observed in prior research. In this narrative review, we briefly describe methods for generating EFT cues, the content of EFT cues, common control conditions for experiments utilizing EFT, and considerations for cue delivery and implementation. Where possible, we make suggestions for current best practices in each category while identifying gaps in knowledge and potential areas of future research. Finally, we conclude by using the NIH Stage model to better frame the current state of the literature on EFT and propose gaps to be addressed if EFT is to be both an efficacious and effective behavioral intervention.

Deprivation Has Inconsistent Effects on Delay Discounting: A Review

Delay discounting, the tendency for outcomes to be devalued as they are more temporally remote, has implications as a target for behavioral interventions. Because of these implications, it is important to understand how different states individuals may face, such as deprivation, influence the degree of delay discounting. Both dual systems models and state-trait views of delay discounting assume that deprivation may result in steeper delay discounting. Despite early inconsistencies and mixed results, researchers have sometimes asserted that deprivation increases delay discounting, with few qualifications. The aim of this review was to determine what empirical effect, if any, deprivation has on delay discounting. We considered many kinds of deprivation, such as deprivation from sleep, drugs, and food in humans and non-human animals. For 23 studies, we analyzed the effect of deprivation on delay discounting by computing effect sizes for the difference between delay discounting in a control, or baseline, condition and delay discounting in a deprived state. We discuss these 23 studies and other relevant studies found in our search in a narrative review. Overall, we found mixed effects of deprivation on delay discounting. The effect may depend on what type of deprivation participants faced. Effect sizes for deprivation types ranged from small for sleep deprivation (Hedge's gs between −0.21 and 0.07) to large for opiate deprivation (Hedge's gs between 0.42 and 1.72). We discuss possible reasons why the effect of deprivation on delay discounting may depend on deprivation type, including the use of imagined manipulations and deprivation intensity. The inconsistency in results across studies, even when comparing within the same type of deprivation, indicates that more experiments are needed to reach a consensus on the effects of deprivation on delay discounting. A basic understanding of how states affect delay discounting may inform translational efforts.

Temporal discounting as a candidate behavioral marker of obesity

Although obesity is a result of processes operating at multiple levels, most forms result from decision-making behavior. The aim of this review was to examine the candidacy of temporal discounting (TD) (i.e. the reduction in the value of a reinforcer as a function of the delay to its receipt) as a behavioral marker of obesity. For this purpose, we assessed whether TD has the ability to: identify risk for obesity development, diagnose obesity, track obesity progression, predict treatment prognosis/outcomes, and measure treatment effectiveness. Three databases (Pubmed, PsycINFO, and Web of Science) were searched using a combination of terms related to TD and obesity. A total of 153 papers were reviewed. Several areas show strong evidence of TD's predictive utility as a behavioral marker of obesity (e.g., distinguishing obese from non obese). However, other areas have limited and/or mixed evidence (e.g., predicting weight change). Given the positive relationship for TD in the majority of domains examined, further consideration for TD as a behavioral marker of obesity is warranted.

Examining the Relationship Between Delay Discounting, Delay Aversion, Diabetes Self-care Behaviors, and Diabetes Outcomes in U.S. Adults With Type 2 Diabetes

OBJECTIVE

Delay discounting and delay aversion are emerging areas for understanding diabetes management; however, few data exist on their relationship with multiple diabetes self-care behaviors and diabetes outcomes.

RESEARCH DESIGN AND METHODS

This cross-sectional study included 356 adults with type 2 diabetes across three racial/ethnic groups receiving care from two primary care clinics. The primary predictors were delay discounting and delay aversion. Outcomes included self-care behaviors, quality of life (QOL; mental health component score [MCS], physical component score), and A1C. Multiple linear regression models were run to examine the association between predictors and the outcomes, A1C, QOL, and each self-care behavior.

RESULTS

Higher delay discounting was associated with lower engagement in self-care behaviors for general diet (B = -0.06; 95% CI -0.12; -0.01), specific diet (B = -0.07; 95% CI -0.12; -0.03), and foot care (B = -0.10; 95% CI -0.17; -0.02). Higher delay aversion was associated with lower engagement in self-care behaviors for general diet (B = -0.06; 95% CI -0.10; -0.01), specific diet (B = -0.03; 95% CI -0.07; -0.01), foot care (B = -0.11; 95% CI -0.17; -0.05), and lower MCS (B = -0.38; 95% CI -0.71; -0.06).

CONCLUSIONS

In a diverse sample of adults with type 2 diabetes, higher delay discounting and higher delay aversion were significantly related to lower engagement in self-care behaviors. High delay aversion was specifically related to lower QOL. These findings offer new knowledge by highlighting the role that delay-related behaviors may have in the performance of self-care behaviors and the impact on QOL. Work is needed to further elucidate these relationships. Specifically, these results highlight the importance of targeting value and decision-making for diabetes self-management.

Associations between shopper impulsivity and cyclical food purchasing: Results from a prospective trial of low-income households receiving monthly benefits

Supplemental Nutrition Assistance Program (SNAP) benefits are rapidly depleted after distribution. This phenomenon, known as the benefit cycle, is associated with poor nutrition and health outcomes. Proposed interventions targeting the benefit cycle often focus on impulsive decision-making. However, it remains unclear whether shopper impulsivity is associated with food purchasing behavior. Using data from a prospective trial, we evaluate whether shopper impulsivity is associated with food purchasing behavior before and after households receive nutrition assistance. In this study, 249 low-income households in the Minneapolis-St. Paul, Minnesota, metropolitan area received monthly benefits for three months. Overall impulsivity and impulsivity subtraits of the primary shopper was assessed using the Barratt Impulsiveness Scale-11. Both total food expenditures and expenditures for two specific categories (fruits and vegetables, and foods high in added sugar) were evaluated. Generalized estimating equations were used to model household expenditures as a function of week since benefit distribution, impulsivity, and their interaction. Results showed that during the benefit period, food expenditures were cyclical and patterned by impulsivity. Shoppers with greater overall impulsivity spent $40.62 more in week 1 (p < 0.001). While more impulsive shoppers spent more on foods high in added sugar throughout the month (p < 0.05 for all weeks), no patterns were observed for fruits and vegetables. These findings suggest that greater impulsivity exacerbates cyclical food purchasing behavior. The impact of shopper impulsivity is especially notable for expenditures on foods high in added sugar. SNAP educational interventions to mitigate the benefit cycle may be strengthened by focusing on more impulsive shoppers and on strategies to reduce impulsive purchases of foods high in added sugar.

An ecological momentary episodic future thinking intervention on mother's weekly food purchases

BACKGROUND

Imagining one's own future (episodic future thinking, EFT) has helped mothers with overweight purchase healthier groceries during an online shopping task in the laboratory. The present study explored whether delivering an EFT intervention to participants' devices via an ecological momentary intervention (EMI) tool would help mothers purchase healthier food at brick-and-mortar stores.

METHOD

Participants (N = 43, mothers 31-52 years of age, BMI ≥ 24.9 kg/m2) were randomized to EFT or standardized episodic thinking (SET). EFT cues include a positive and vivid description of future events while SET cues focus on the recent experience of playing games in the laboratory. Cues were uploaded to participant profiles on an EMI site. Participants were trained on how to read and listen to cues as well as how to detail purchases. Participants received text reminders to listen to cues before shopping and returned with receipts the following day. Receipt data was analyzed to derive dependent variables, calories, and nutrients purchased per person. Correlations were used to analyze associations between study variables of interest, and ANOVAs were conducted to compare dietary variables by group.

RESULTS

Participants in the EFT group purchased fewer calories, fewer grams of fat, fewer grams of saturated fat, and fewer miligrams of sodium than participants in the SET control group.

CONCLUSION

Delivering EFT cues to participant devices may be a promising way to improve the calorie and nutrient content of food purchases. Future research should include a longer follow-up and analyze calorie changes over time. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Time preferences, diabetes self-management behaviours and outcomes: a systematic review

AIM

Time preferences, i.e. individuals' degree of patience/impatience in intertemporal choice, have been found to be associated with suboptimal health behaviours and health outcomes such as smoking, physical inactivity, unhealthy food intake and obesity. In this systematic review, we aimed to synthesise reported associations between time preferences, diabetes self-management behaviours, including use of diabetes technology, and outcomes.

METHODS

We searched MEDLINE, EMBASE, PsycINFO, CINAHL, EconLit and all databases in the Web of Science Core Collection. Peer-reviewed studies of people with diabetes that included at least one diabetes-related behaviour or outcome and a measure of time preferences were included. Non-English language studies were excluded.

RESULTS

A total of 961 records were identified, of which 12 articles were included. Three studies analysed both time-consistent and time-inconsistent preferences, three studies solely analysed time-inconsistent preferences and six studies did not explicitly define a time preference model. Measured outcomes across studies included self-care activities, such as medication-taking, exercising and eating a healthy diet, and biomedical outcomes, such as HbA_1c and diabetes-related complications. There were 10 cross-sectional studies and two panel-data studies. No studies explicitly analysed the relationship between time preferences and diabetes technology use.

CONCLUSIONS

Associations between measures of time preferences, diabetes self-management behaviours and clinical outcomes exist. Higher discount rates determined by both time-consistent and time-inconsistent models predict less diabetes-related self-care and worse outcomes. These findings may add to explanations of the observed variation in diabetes-related health and provide new insights for tailoring interventions and policies aimed at improving diabetes self-management.

Cognitive training on eating behaviour and weight loss: A meta-analysis and systematic review

Cognitive deficits play a role in the development and maintenance of overeating and obesity, and cognitive training in obesity refers to a family of interventions aimed at reducing overeating and obesity by improving these cognitive deficits. In this review, we synthesize the current literature on these issues by conducting a meta-analysis of studies investigating the effects of cognitive trainings on eating behaviour and presenting a systematic review of studies investigating the effects of cognitive trainings on weight loss. We examined 66 independent experiments that examined the effects of cognitive training aimed at reducing cognitive bias or improving executive control on eating behaviour and weight loss. Overall, inhibition training, attention bias modification training, and episodic future thinking training significantly influenced eating behaviour; however, approach/avoidance training did not significantly influence eating behaviour. Moderator analyses indicated that the effect of inhibition training on eating behaviour was moderated by training task and food novelty, the effect of approach/avoidance training was moderated by food type, and the effect of episodic future thinking training was moderated by type of episodic future thinking. Literature reviewed on cognitive training and weight loss provided preliminary support for the effects of food-specific inhibition training on weight loss from pre-intervention to post intervention. However, because most of the included studies focused on short-term outcomes in normal-weight samples, longer duration studies in clinical populations (eg, individuals with obesity) are needed to examine the generalizability of these results.