Effects of red meat taxes and warning labels on food groups selected in a randomized controlled trial.

BACKGROUND: High consumption of red and processed meat contributes to both health and environmental harms. Warning labels and taxes for red meat reduce selection of red meat overall, but little is known about how these potential policies affect purchases of subcategories of red meat (e.g., processed versus unprocessed) or of non-red-meat foods (e.g., cheese, pulses) relevant to health and environmental outcomes. This study examined consumer responses to warning labels and taxes for red meat in a randomized controlled trial. METHODS: In October 2021, we recruited 3,518 US adults to complete a shopping task in a naturalistic online grocery store. Participants were randomly assigned to one of four arms: control (no warning labels or tax), warning labels only (health and environmental warning labels appeared next to products containing red meat), tax only (prices of products containing red meat were increased 30%) or combined warning labels + tax. Participants selected items to hypothetically purchase, which we categorized into food groups based on the presence of animal- and plant-source ingredients (e.g., beef, eggs, pulses), meat processing level (e.g., processed pork versus unprocessed pork), and meat species (e.g., beef versus pork). We assessed the effects of the warning labels and tax on selections from each food group. RESULTS: Compared to control, all three interventions led participants to select fewer items with processed meat (driven by reductions in processed pork) and (for the tax and warning labels + tax interventions only) fewer items with unprocessed meat (driven by reductions in unprocessed beef). All three interventions also led participants to select more items containing cheese, while only the combined warning labels + tax intervention led participants to select more items containing processed poultry. Except for an increase in selection of pulses in the tax arm, the interventions did not affect selections of fish or seafood (processed or unprocessed), eggs, or plant-based items (pulses, nuts & seeds, tofu, meat mimics, grains & potatoes, vegetables). CONCLUSIONS: Policies to reduce red meat consumption are also likely to affect consumption of other types of foods that are relevant to both health and environmental outcomes. TRIAL REGISTRATION: NCT04716010 on www. CLINICALTRIALS: gov .

Developing messages to encourage healthy, sustainable dietary substitutions: A qualitative study with US emerging adults.

Prior research shows that adopting simple dietary substitutions (e.g., replacing beef with poultry or plant-based entrees) can improve dietary quality and reduce the negative environmental consequences of food production, but little is known about how to encourage people to adopt these substitutions. This study aimed to examine reactions to messages encouraging healthy, sustainable dietary substitutions among emerging adults ages 18-25. We conducted four online focus groups with a diverse sample of US emerging adults (n = 28; 61% female). Focus groups explored emerging adults' reactions to messages encouraging them to adopt three target dietary substitutions: replacing beef and pork with poultry and plant-based entrees; replacing juice with whole fruit; and replacing dairy milk with non-dairy milk. We transcribed discussions verbatim and adopted a thematic approach to analyzing the transcripts. Results showed that participants perceived messages to be most effective at encouraging the target dietary substitutions when the messages: encouraged specific, achievable dietary changes; linked these dietary changes to clear consequences; included personally relevant content; included statistics; were succinct; and used a positive tone. Across the target dietary substitutions, two message topics (small changes, big benefits, which emphasized how small dietary changes can have large positive health and environmental impacts, and warning, which discussed the negative health and environmental impacts of dietary choices) were generally perceived to be most effective. A few participants expressed doubt that the target dietary substitutions would have meaningful environmental impacts. Results suggest that campaign messages to encourage healthy, sustainable dietary substitutions may be more effective if the messages make the target dietary substitutions seem achievable and use statistics to clearly describe the positive impacts of making these changes.

Impact of taxes and warning labels on red meat purchases among US consumers: A randomized controlled trial.

BACKGROUND: Policies to reduce red meat intake are important for mitigating climate change and improving public health. We tested the impact of taxes and warning labels on red meat purchases in the United States. The main study question was, will taxes and warning labels reduce red meat purchases? METHODS AND FINDINGS: We recruited 3,518 US adults to participate in a shopping task in a naturalistic online grocery store from October 18, 2021 to October 28, 2021. Participants were randomized to one of 4 conditions: control (no tax or warning labels, n = 887), warning labels (health and environmental warning labels appeared next to products containing red meat, n = 891), tax (products containing red meat were subject to a 30% price increase, n = 874), or combined warning labels + tax (n = 866). We used fractional probit and Poisson regression models to assess the co-primary outcomes, percent, and count of red meat purchases, and linear regression to assess the secondary outcomes of nutrients purchased. Most participants identified as women, consumed red meat 2 or more times per week, and reported doing all of their household's grocery shopping. The warning, tax, and combined conditions led to lower percent of red meat-containing items purchased, with 39% (95% confidence interval (CI) [38%, 40%]) of control participants' purchases containing red meat, compared to 36% (95% CI [35%, 37%], p = 0.001) of warning participants, 34% (95% CI [33%, 35%], p < 0.001) of tax participants, and 31% (95% CI [30%, 32%], p < 0.001) of combined participants. A similar pattern was observed for count of red meat items. Compared to the control, the combined condition reduced calories purchased (-312.0 kcals, 95% CI [-590.3 kcals, -33.6 kcals], p = 0.027), while the tax (-10.4 g, 95% CI [-18.2 g, -2.5 g], p = 0.01) and combined (-12.8 g, 95% CI [-20.7 g, -4.9 g], p = 0.001) conditions reduced saturated fat purchases; no condition affected sodium purchases. Warning labels decreased the perceived healthfulness and environmental sustainability of red meat, while taxes increased perceived cost. The main limitations were that the study differed in sociodemographic characteristics from the US population, and only about 30% to 40% of the US population shops for groceries online. CONCLUSIONS: Warning labels and taxes reduced red meat purchases in a naturalistic online grocery store. Trial Registration: http://www.clinicaltrials.gov/ NCT04716010.

How pictorial warnings change parents' purchases of sugar-sweetened beverage for their children: mechanisms of impact.

BACKGROUND: Pictorial health warnings on sugar-sweetened beverages (SSBs) are a promising policy for preventing diet-related disease in children. A recent study found that pictorial warnings reduced parents' purchases of SSBs for their children by 17%. However, the psychological mechanisms through which warnings affect parental behavior remain unknown. We aimed to identify the mechanisms that explain how pictorial warnings affect parents' SSB purchasing behavior for their children using secondary data from a randomized trial. METHODS: In 2020-2021, parents of children ages 2 to 12 years (n = 325) completed a shopping task in a convenience store laboratory in North Carolina, USA. Participants were randomly assigned to a pictorial warnings arm (SSBs displayed pictorial health warnings about type 2 diabetes and heart damage) or a control arm (SSBs displayed a barcode label). Parents then bought a beverage for their child and took a survey measuring 11 potential psychological mediators, selected based on health behavior theories and a model explaining the impact of tobacco warnings. We conducted simple mediation analyses to identify which of the 11 mechanisms mediated the impact of exposure to pictorial warnings on purchasing any SSBs for their children. RESULTS: Two of the 11 constructs were statistically significant mediators. First, the impact of pictorial warnings on the likelihood of purchasing any SSB was mediated by parents' perceptions that SSBs were healthier for their child (mediated effect= -0.17; 95% CI = - 0.33, - 0.05). Second, parents' intentions to serve SSBs to their children also mediated the effect of warnings on likelihood of purchasing any SSB (mediated effect= -0.07, 95% CI=-0.21, - 0.003). CONCLUSIONS: Pictorial warnings reduced parents' purchases of SSBs for their children by making parents think SSBs are less healthful for their children and reducing their intentions to serve SSBs to their children. Communication approaches that target healthfulness perceptions and intentions to serve SSBs may motivate parents to buy fewer SSBs for their children.

Should messages discourage sugary drinks, encourage water, or both? A randomized experiment with U.S. parents.

Campaigns to improve beverage consumption typically focus on discouraging unhealthy beverages (e.g., soda), encouraging healthy beverages (e.g., water), or both. It remains unclear which of these strategies is most effective. We recruited a national convenience sample of U.S. parents of children ages 2-12 (n = 1078, 48% Latino[a]) to complete an online survey in 2019. We randomly assigned participants to view: 1) a control message, 2) a soda discouragement message, 3) a water encouragement message, or 4) both soda discouragement and water encouragement messages shown side-by-side in random arrangement. Intervention messages mimicked New York City's "Pouring on the Pounds" campaign. Participants rated messages on perceived effectiveness for discouraging soda consumption and encouraging water consumption (1-5 response scales) and reported feelings and intentions about drinking soda and water (1-7 scales). Compared to those with no exposure, participants who viewed the soda discouragement message reported higher perceived discouragement from drinking soda (Average Differential Effect [ADE] = 1.18), more negative feelings toward drinking soda (ADE = 0.83) and stronger intentions to avoid drinking soda (ADE = 0.45) (ps < 0.001). The soda discouragement message also exerted beneficial effects on perceived effectiveness, feelings, and intentions related to water consumption (ADEs = 0.33-0.68; ps < 0.001). Exposure to the water encouragement message had beneficial effects on outcomes related to water consumption (ADEs = 0.28-0.81, ps < 0.001), but limited impact on outcomes related to soda consumption. Across outcomes, results indicated diminishing returns from exposure to both message types. Messaging campaigns discouraging unhealthy beverages may be more promising for improving beverage consumption than messages only promoting healthier beverages.

Effects of in-store marketing on food and beverage purchases: a longitudinal study of households with children.

OBJECTIVE: Most food retailers display foods in prominent locations as a marketing strategy (i.e. 'placement promotions'). We examined the extent to which households with children change their food and beverage purchases in response to these promotions. DESIGN: We analysed a novel dataset of all products promoted in two supermarkets from 2016 to 2017, including promotion dates and locations (e.g. aisle endcaps and front registers). We linked promotions to all purchases from the supermarkets from 2016 to 2017 by a cohort of households with children. We calculated the number of weekly promotions in each of thirteen food and beverage groups (e.g. bread; candy) and used fixed effects regressions to estimate associations between number of weekly promotions and households' weekly food purchases, overall and by Supplemental Nutrition Assistance Program (SNAP) participation. SETTING: Two large supermarkets in Maine, USA. PARTICIPANTS: Eight hundred and twenty-one households with children. RESULTS: Most promotions (74 %) were for less healthy foods. The most promoted food groups were sweet and salty snacks (mean = 131·0 promotions/week), baked goods (mean = 68·2) and sugar-sweetened beverages (mean = 41·6). Households generally did not change their food group purchases during weeks when they were exposed to more promotions for those groups, except that a 1-sd increase in endcap candy promotions (about 1 promotion/week) was associated with $0·19/week (about 14·5 %) increase in candy purchases among SNAP nonparticipants (adjusted P < 0·001). CONCLUSIONS: In-store placement promotions for food groups were generally not associated with purchases of promoted food groups, perhaps because exposure to unhealthy food marketing was consistently high. Substantial changes to in-store food marketing may be needed to promote healthier purchases.

The impact of pictorial health warnings on purchases of sugary drinks for children: A randomized controlled trial.

BACKGROUND: Pictorial warnings on tobacco products are promising for motivating behavior change, but few studies have examined pictorial warnings for sugary drinks, especially in naturalistic environments. This study aimed to examine the impact of pictorial warnings on parents' purchases of sugary drinks for their children in a naturalistic store laboratory. METHODS AND FINDINGS: Parents of children ages 2 to 12 (n = 325, 25% identifying as Black, 20% Hispanic) completed a shopping task in a naturalistic store laboratory in North Carolina. Participants were randomly assigned to a pictorial warnings arm (sugary drinks displayed pictorial health warnings about type 2 diabetes and heart damage) or a control arm (sugary drinks displayed a barcode label). Parents selected 1 beverage and 1 snack for their child, as well as 1 household good; one of these items was selected for them to purchase and take home. The primary outcome was whether parents purchased a sugary drink for their child. Secondary outcomes included reactions to the trial labels, attitudes toward sugary drinks, and intentions to serve their child sugary drinks. Pictorial warnings led to a 17-percentage point reduction in purchases of sugary drinks (95% CI for reduction: 7% to 27%), with 45% of parents in the control arm buying a sugary drink for their child compared to 28% in the pictorial warning arm (p = 0.002). The impact of pictorial warnings on purchases did not differ by any of the 13 participant characteristics examined (e.g., race/ethnicity, income, education, and age of child). Pictorial warnings also led to lower calories (kcal), purchased from sugary drinks (82 kcal in the control arm versus 52 kcal in the pictorial warnings arm, p = 0.003). Moreover, pictorial warnings led to lower intentions to serve sugary drinks to their child, feeling more in control of healthy eating decisions, greater thinking about the harms of sugary drinks, stronger negative emotional reactions, greater anticipated social interactions, lower perceived healthfulness of sugary drinks for their child, and greater injunctive norms to limit sugary drinks for their child (all p < 0.05). There was no evidence of difference between trial arms on noticing of the labels, appeal of sugary drinks, perceived amount of added sugar in sugary drinks, risk perceptions, or perceived tastiness of sugary drinks (all p > 0.05). CONCLUSIONS: Pictorial warnings reduced parents' purchases of sugary drinks for their children in this naturalistic trial. Warnings on sugary drinks are a promising policy approach to reduce sugary drink purchasing in the US. TRIAL REGISTRATION: The trial design, measures, power calculation, and analytic plan were registered before data collection at www.clinicaltrials.gov NCT04223687.

Purchases of Nontaxed Foods, Beverages, and Alcohol in a Longitudinal Cohort After Implementation of the Philadelphia Beverage Tax.

BACKGROUND: Evidence suggests that sweetened beverage taxes reduce taxed beverage purchases, but few studies have used individual-level data to assess whether these taxes affect purchases of nontaxed foods, beverages, and alcohol. Additionally, research has not examined whether sweetened beverage taxes influence restaurant purchases. OBJECTIVES: We assessed changes in individuals' purchases of taxed beverage types; low-calorie/low-added-sugar nontaxed beverages; high-calorie/high-added-sugar nontaxed beverages, foods, and alcohol; and beverages from restaurants following implementation of the 1.5 cent-per-ounce Philadelphia sweetened beverage tax. METHODS: A longitudinal cohort of adult sugar-sweetened beverage consumers in Philadelphia (n = 306; 67% female; mean age: 43.9 years) and Baltimore (n = 297; comparison city without a beverage tax; 58% female; mean age: 41.7 years) submitted all food and beverage receipts during 2-week periods at baseline and at 3, 6, and 12 months posttax. Difference-in-differences analyses compared changes in purchases from pre- to posttax in Philadelphia to changes in Baltimore. RESULTS: Purchases of taxed juice drinks [ratio of incidence rate ratios (RIRR) = 0.62; 95% CI, 0.42-0.91], but not other taxed beverage types, decreased in Philadelphia compared to Baltimore following the tax. Analyses did not find changes in purchases of low-calorie/low-added-sugar nontaxed beverages, such as water or milk. Additionally, analyses did not find increases in purchases of most high-calorie/high-added-sugar nontaxed products, including alcohol, juice, candy, sweet snacks, salty snacks, and desserts. Purchases of beverage concentrates increased in Philadelphia (RIRR = 2.22; 95% CI, 1.39-3.54). CONCLUSIONS: In this difference-in-differences analysis, the Philadelphia beverage tax was associated with reduced purchases of taxed juice drinks. Purchases of beverage concentrates increased after the tax, but no increases were observed for other high-calorie/high-added-sugar nontaxed foods, beverages, or alcohol.

Reactions to messages about smoking, vaping and COVID-19: two national experiments.

INTRODUCTION: The pace and scale of the COVID-19 pandemic, coupled with ongoing efforts by health agencies to communicate harms, have created a pressing need for data to inform messaging about smoking, vaping, and COVID-19. We examined reactions to COVID-19 and traditional health harms messages discouraging smoking and vaping. METHODS: Participants were a national convenience sample of 810 US adults recruited online in May 2020. All participated in a smoking message experiment and a vaping message experiment, presented in a random order. In each experiment, participants viewed one message formatted as a Twitter post. The experiments adopted a 3 (traditional health harms of smoking or vaping: three harms, one harm, absent) × 2 (COVID-19 harms: one harm, absent) between-subjects design. Outcomes included perceived message effectiveness (primary) and constructs from the Tobacco Warnings Model (secondary: attention, negative affect, cognitive elaboration, social interactions). RESULTS: Smoking messages with traditional or COVID-19 harms elicited higher perceived effectiveness for discouraging smoking than control messages without these harms (all p <0.001). However, including both traditional and COVID-19 harms in smoking messages had no benefit beyond including either alone. Smoking messages affected Tobacco Warnings Model constructs and did not elicit more reactance than control messages. Smoking messages also elicited higher perceived effectiveness for discouraging vaping. Including traditional harms in messages about vaping elicited higher perceived effectiveness for discouraging vaping (p <0.05), but including COVID-19 harms did not. CONCLUSIONS: Messages linking smoking with COVID-19 may hold promise for discouraging smoking and may have the added benefit of also discouraging vaping.

Awareness of and reactions to health and environmental harms of red meat among parents in the United States.

OBJECTIVE: Evidence of the health and environmental harms of red meat is growing, yet little is known about which harms may be most impactful to include in meat reduction messages. This study examined which harms consumers are most aware of and which most discourage them from wanting to eat red meat. DESIGN: Within-subjects randomised experiment. Participants responded to questions about their awareness of, and perceived discouragement in response to, eight health and eight environmental harms of red meat presented in random order. Discouragement was assessed on a 1-to-5 Likert-type scale. SETTING: Online survey. PARTICIPANTS: 544 US parents. RESULTS: A minority of participants reported awareness that red meat contributes to health harms (ranging from 8 % awareness for prostate cancer to 28 % for heart disease) or environmental harms (ranging from 13 % for water shortages and deforestation to 22 % for climate change). Among specific harms, heart disease elicited the most discouragement (mean = 2·82 out of 5), followed by early death (mean = 2·79) and plants and animals going extinct (mean = 2·75), though most harms elicited similar discouragement (range of means, 2·60-2·82). In multivariable analyses, participants who were younger, identified as Black, identified as politically liberal, had higher general perceptions that red meat is bad for health and had higher usual red meat consumption reported being more discouraged from wanting to eat red meat in response to health and environmental harms (all P < 0·05). CONCLUSIONS: Messages about a variety of health and environmental harms of red meat could inform consumers and motivate reductions in red meat consumption.

Testing front-of-package warnings to discourage red meat consumption: a randomized experiment with US meat consumers.

BACKGROUND: Reducing red meat is a strategy to improve public health and mitigate climate change in the United States and other high-income countries. Policies requiring warnings on the front of red meat packages are a promising intervention to shift consumers towards healthier and more sustainable food choices. We aimed to explore participants' reactions to health and environmental warning messages about red meat. METHODS: Between June and July 2020, we recruited a national convenience sample of US red meat consumers (n = 1,235; mean age 44 years) for an online survey. Participants were randomly assigned to one of four label conditions: no-label control, health warning, environment warning, and combined health and environment warning (both warnings shown side-by-side). Participants viewed three types of burritos (red meat [steak], chicken, and vegetarian) and selected their preferred item (primary outcome), the item they perceived to be most damaging to health, and the item they perceived to be most damaging to the environment (secondary outcomes). Participants then viewed their assigned warning on a series of other red meat products (no-label control participants were randomly re-assigned to one of the warning conditions) and rated the warnings on perceived message effectiveness, believability, negative emotions, perceived risk, attention, and learning something new. Finally, participants reported their intentions to reduce red meat consumption. RESULTS: There were no significant differences in selection of the steak burrito between label conditions or in selection of the item most damaging to the environment. Those exposed to the health warning were more likely to select the steak burrito as most damaging to health compared to those exposed to other label conditions (health 73 %, combined 64 %, environment 60 %, no-label control 63 %, p < 0.05). The combined and health warnings elicited higher perceived message effectiveness ratings than the environment warning (combined mean 2.91, health 2.84, environment 2.61, p < 0.05). CONCLUSIONS: Warnings did not have a significant effect on item preference in the choice experiment. However, combined and health warnings performed better than the environment warning across a variety of warning label reaction measures. More research will be needed to understand whether warnings elicit behavioral change in real-world environments. TRIAL REGISTRATION: Analyses and hypotheses were preregistered on https://aspredicted.org/ph7mb.pdf on 23 June 2020.

Designing warnings for sugary drinks: A randomized experiment with Latino parents and non-Latino parents.

Sugary drink warnings are a promising policy for reducing sugary drink consumption, but it remains unknown how to design warnings to maximize their impact overall and among diverse population groups, including parents of Latino ethnicity and parents with low English use. In 2019, we randomized US parents of children ages 2-12 (n = 1078, 48% Latino ethnicity, 13% low English use) to one topic (one of four warnings, or a neutral control), which they viewed on three designs (text-only, icon, and graphic) to assess reactions to the various warnings on sugary drinks. All warning topics were perceived as more effective than the control (average differential effect [ADE] ranged from 1.77 to 1.84 [5-point Likert scale], all p < .001). All warning topics also led to greater thinking about harms of sugary drinks (all p < .001) and lower purchase intentions (all p < .01). Compared to text-only warnings, icon (ADE = 0.18) and graphic warnings (ADE = 0.30) elicited higher perceived message effectiveness, as well as greater thinking about the harms of sugary drinks, lower perceived healthfulness, and lower purchase intentions (all p < .001). The impact of icon warnings (vs. text warnings) was stronger for parents with low English use, compared to those with high English use (p = .024). Similarly, the impact of icon (vs. text warnings) was stronger for Latino parents than non-Latino parents (p = .034). This experimental study indicates that many warning topics hold promise for behavior change and that including images with warnings could increase warning efficacy, particularly among Latino parents and parents with low English use. Clinical Trial Registration: NCT04382599.

Is late bedtime an overlooked sleep behaviour? Investigating associations between sleep timing, sleep duration and eating behaviours in adolescence and adulthood.

OBJECTIVE: To examine whether bedtime is associated with usual sleep duration and eating behaviour among adolescents, emerging adults and young adults. DESIGN: Cross-sectional multivariable regression models, stratified by developmental stage, to examine: (1) association between bedtime and sleep duration and (2) associations between bedtime and specific eating behaviours at each developmental period, controlling for sleep duration. All models adjusted for sociodemographic characteristics, depressive symptoms and screen time behaviours. SETTING: National Longitudinal Study of Adolescent to Adult Health, waves I-IV, USA. PARTICIPANTS: A national probability sample surveyed in adolescence (aged 12-18 years, wave I: 1994-1995, n 13 048 and wave II: 1996, n 9438), emerging adulthood (aged 18-24 years, wave III: 2001-2002, n 9424) and young adulthood (aged 24-34 years, wave IV: 2008, n 10 410). RESULTS: Later bedtime was associated with shorter sleep duration in all developmental stages, such that a 1-h delay in bedtime was associated with 14-33 fewer minutes of sleep per night (Ps < 0·001). Later bedtime was also associated with lower odds of consuming healthier foods (i.e. fruits, vegetables; range of adjusted OR (AOR), 0·82-0·93, Ps < 0·05) and higher odds of consuming less healthy foods and beverages (i.e. soda, pizza, desserts and sweets; range of AOR, 1·07-1·09, Ps < 0·05). Later bedtime was also associated with more frequent fast-food consumption and higher sugar-sweetened beverage consumption (Ps < 0·05). CONCLUSIONS: Later bedtime was associated with shorter sleep duration and less healthy eating behaviours. Bedtime may be a novel behaviour to address in interventions aiming to improve sleep duration and dietary intake.

Awareness of and reactions to the health harms of sugary drinks: An online study of U.S. parents.

Evidence about the health problems associated with sugary drink consumption is well-established. However, little is known about which sugary drink health harms are most effective at changing consumers' behavior. We aimed to identify which harms people were aware of and most discouraged them from wanting to buy sugary drinks. Participants were a national convenience sample of diverse parents (n = 1,058), oversampled for Latino parents (48%). Participants rated a list of sugary drink-related health harms occurring in children (7 harms) and in adults (15 harms). Outcomes were awareness of each harm and how much each harm discouraged parents from wanting to purchase sugary drinks. Most participants were aware that sugary drinks contribute to tooth decay in children (75%) and weight gain in both children (73%) and adults (69%). Few participants were aware that sugary drinks contribute to adult infertility (16%), arthritis (18%), and gout (18%). All health harms were rated highly in terms of discouraging parents from wanting to buy sugary drinks (range: 3.59-4.11 on a 1-5 scale), with obesity, pre-diabetes, and tooth decay eliciting the highest discouragement ratings. Harm-induced discouragement was higher for participants who were aware of more health harms (B = 0.05, p < 0.0001), identified as female (B = 0.15 compared to male, p = 0.02), or had an annual household income of $50,000 or more (B = 0.16 compared to less than $50,000, p = 0.03). These findings suggest health messages focused on a variety of health harms could raise awareness and discourage sugary drink purchases.

Sugary drink warnings: A meta-analysis of experimental studies.

BACKGROUND: Policymakers worldwide are considering requiring warnings for sugary drinks. A growing number of experimental studies have examined sugary drink warnings' impacts, but no research to our knowledge has synthesized this literature. To inform ongoing policy debates, this study aimed to identify the effects of sugary drink warnings compared with control conditions. METHODS AND FINDINGS: We systematically searched 7 databases on June 21, 2019, and October 25, 2019. We also searched reference lists of relevant articles. Two investigators independently screened titles, abstracts, and full texts to identify peer-reviewed articles that used an experimental protocol to examine the effects of sugary drink warnings compared to a control condition. Two investigators independently extracted study characteristics and effect sizes from all relevant full-text articles. We meta-analyzed any outcome assessed in at least 2 studies, combining effect sizes using random effects meta-analytic procedures. Twenty-three experiments with data on 16,241 individuals (mean proportion female, 58%) were included in the meta-analysis. Most studies took place in Latin America (35%) or the US or Canada (46%); 32% included children. Relative to control conditions, sugary drink warnings caused stronger negative emotional reactions (d = 0.69; 95% CI: 0.25, 1.13; p = 0.002) and elicited more thinking about the health effects of sugary drinks (d = 0.65; 95% CI: 0.29, 1.01; p < 0.001). Sugary drink warnings also led to lower healthfulness perceptions (d = -0.22; 95% CI: -0.27, -0.17; p < 0.001) and stronger disease likelihood perceptions (d = 0.15; 95% CI: 0.06, 0.24; p = 0.001). Moreover, sugary drink warnings reduced both hypothetical (d = -0.32; 95% CI: -0.44, -0.21; p < 0.001) and actual consumption and purchasing behavior (d = -0.17; 95% CI: -0.30, -0.04; p = 0.012). Statistically significant effects were not observed for perceptions of added sugar or positive sugary drink attitudes (p's > 0.10). Moderation analyses revealed that health warnings (e.g., "Beverages with added sugar contribute to obesity") led to greater reductions in hypothetical sugary drink purchases than did nutrient warnings (e.g., "High in sugar"; d = -0.35 versus -0.18; Qb = 4.04; p = 0.04). Limitations of this study include that we did not review grey literature and that we were unable to conduct moderation analyses for several prespecified moderators due to an insufficient number of studies. CONCLUSIONS: This international body of experimental literature supports sugary drink warnings as a population-level strategy for changing behavior, as well as emotions, perceptions, and intentions. PROTOCOL REGISTRY: PROSPERO ID 146405.

Sleep duration and body mass: direction of the associations from adolescence to young adulthood.

Research suggests that sleep duration and obesity are related, but the direction of this association remains uncertain. We applied autoregressive cross-lag models to evaluate the directionality of the relationship between sleep duration and BMI from adolescence through emerging and young adulthood, life stages where the risk for developing obesity are particularly high. Using data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), we examined sex-stratified associations between sleep duration and BMI in this cohort from adolescence (ages 12-18, year 1996), to emerging adulthood (ages 18-24, 2001-2002), to young adulthood (ages 24-32, 2008), controlling for key confounders. For both males and females, higher BMI during an earlier developmental stage was associated with shorter sleep duration in the subsequent stage (both Bs = -0.02, ps < 0.01). However, sleep duration at an earlier developmental stage was not associated with BMI at the subsequent stage. Findings suggest that researchers should be cautious when interpreting cross-sectional relationships between sleep and BMI, as higher BMI may precede shorter sleep during adolescence to young adulthood. Researchers may also wish to account for potential bi-directional associations when modeling sleep and BMI using longitudinal data.

Implementation of the First US Sugar-Sweetened Beverage Tax in Berkeley, CA, 2015-2019.

Objectives. To identify lessons learned from implementation of the nation's first sugar-sweetened beverage (SSB) excise tax in 2015 in Berkeley, California.Methods. We interviewed city stakeholders and SSB distributors and retailers (n = 48) from June 2015 to April 2017 and analyzed records through January 2019.Results. Lessons included the importance of thorough and timely communications with distributors and retailers, adequate lead time for implementation, advisory commissions for revenue allocations, and funding of staff, communications, and evaluation before tax collection begins. Early and robust outreach about the tax and programs funded can promote and sustain public support, reduce friction, and facilitate beverage price increases on SSBs only. No retailer reported raising food prices, indicating that Berkeley's SSB tax did not function as a "grocery tax," as industry claimed. Revenue allocations totaled more than $9 million for public health, nutrition, and health equity through 2021.Conclusions. The policy package, context, and implementation process facilitated translating policy into public health outcomes. Further research is needed to understand long-term facilitators and barriers to sustaining public health benefits of Berkeley's tax and how those differ from facilitators and barriers in jurisdictions facing significant industry-funded repeal efforts.

Health Warnings and Beverage Purchase Behavior: Mediators of Impact.

BACKGROUND: To reduce diet-related chronic disease, policymakers have proposed requiring health warnings on sugar-sweetened beverages (SSBs). Health warnings reduced purchases of these products by 22% in our recent randomized controlled trial, but the mechanisms remain unclear. PURPOSE: We sought to identify the psychological mechanisms that explain why SSB health warnings affect purchase behavior. METHODS: In 2018, we recruited 400 adult SSB consumers to complete a shopping task in a naturalistic convenience store laboratory in North Carolina, USA. We randomly assigned participants to either a health warning arm (all SSBs in the store displayed a text health warning) or to a control arm (SSBs displayed a control label). Participants selected items to purchase with cash. RESULTS: Compared to control labels, health warnings elicited more attention, negative affect, anticipated social interactions, and thinking about harms (range of ds = 0.63-1.34; all p < .001). Health warnings also led to higher injunctive norms about limiting SSB consumption (d = 0.27, p = .008). Except for attention, all of these constructs mediated the effect of health warnings on SSB purchases (all p < .05). In contrast, health warnings did not influence other attitudes or beliefs about SSBs or SSB consumption (e.g., healthfulness, outcome expectations, and response efficacy). CONCLUSIONS: Health warnings on sugar-sweetened beverages affected purchase behavior by eliciting negative emotions, increasing anticipated social interactions, keeping SSBs' harms at top of mind, and shifting norms about beverage consumption. Results are consistent with recent studies of why tobacco warnings influence quitting behavior, pointing toward a general framework for understanding how health warnings affect behavior. CLINICAL TRIALS REGISTRATION: NCT #03511937.

Reactions to graphic and text health warnings for cigarettes, sugar-sweetened beverages, and alcohol: An online randomized experiment of US adults.

We aimed to examine reactions to graphic versus text-only warnings for cigarettes, SSBs, and alcohol. A convenience sample of US adults completed an online survey in 2018 (n = 1352 in the analytic sample). We randomly assigned participants to view a: 1) text-only warning without efficacy information (i.e., message intended to increase consumers' confidence in their ability to stop using the product), 2) text-only warning with efficacy information, 3) graphic warning without efficacy information, or 4) graphic warning with efficacy information. Participants viewed their assigned warning on cigarettes, SSBs, and alcohol, in a random order. Across product types, graphic warnings were perceived as more effective than text-only warnings (p < .001) and led to lower believability, greater reactance (i.e., resistance), more thinking about harms, and lower product appeal (all p < .05); policy support did not differ. Compared to SSB and alcohol warnings, cigarette warnings led to higher perceived message effectiveness, believability, fear, thinking about harms, policy support, and greater reductions in product appeal (all p < .05). The efficacy information did not influence any outcomes. Graphic warnings out-performed text-only warnings on key predictors of behavior despite causing more reactance.