Warning Labels Research Articles

Regulatory Landscape of Cannabis Warning Labels in US States with Legal Retail Nonmedical Cannabis, 2024.

Objectives. To characterize regulatory practices related to nonmedical cannabis warning labels in states across the United States that have legalized retail nonmedical cannabis. Methods. In March 2024, we conducted a content analysis of regulations for nonmedical cannabis warning labels required on product packages in 20 states where, as of March 2024, adults could legally purchase nonmedical cannabis in retail environments. For each state, we examined requirements related to warning label content and characteristics. Results. Required warning label content and characteristics varied widely across states. Only 2 states required a warning about mental health risks (10%) and 2 states required a warning for high potency products on risk of psychosis (10%). No states required front-of-package warning placement, only 2 states required rotating warnings (10%), and 4 states required contrasting colors (20%). Warnings were often verbose (mean = 57 words), vague, and had small or no minimum font size. Conclusions. Opportunities exist for states to improve the alignment of their nonmedical cannabis warning label regulations with evidence that has been generated so far in cannabis effects, cannabis warning efficacy, and warning label design. (Am J Public Health. 2024;114(S8):S681-S684. https://doi.org/10.2105/AJPH.2024.307722).

Ultra-processed food consumption and risk of coronary heart diseases: UK Whitehall II cohort study

Abstract In recent decades, ultra-processed foods (UPFs) intake has increased drastically, sparking concerns about their potential impact on cardiometabolic diseases. However, large-scale cohort studies tracking UPF consumption at multiple time points remain limited. This study explores the prospective association between repeated measures of UPF intake and the risk of coronary heart disease (CHD), along with its secondary endpoints, within the UK Whitehall II study. The analytical sample tracked 7,138 midlife British participants without CHD from baseline. UPF consumption was measured using validated food frequency questionnaire (127 items) and classified by the NOVA system during three phases: 1991/1994 (phase 3), 1997/1999 (phase 5), and 2002/2003 (phase 7). This study assessed the onset of CHD and its secondary endpoints, including CHD and all-cause mortality, through medical exams and hospital records up to 2016 and 2021, respectively. Cox proportional hazards regression models adjusted for socio-demographics, lifestyle factors and total energy intake were used to explore the prospective association between cumulative average UPF intake (in quintiles) and CHD outcomes. During a median follow-up of 13 and 19 years, 589 cases and 1,314 deaths were documented. In multivariable adjusted cox models, the highest UPF consumption quintile versus the lowest quintile was associated with higher CHD incidence [HR:1.26; 95% Confidence Interval (CI): 1.02-1.55; p = 0.03]. Additional adjustment of total energy intake increased the CHD risk by 28% [HR:1.28; 95% CI: 1.03-1.58; p = 0.02]. No significant relationships were found between cumulative average UPF intake and CHD or all-cause mortality. In UK midlife adults, higher UPF intake is prospective associated with increased CHD risk. Although additional research is warranted, these findings emphasize the importance of public awareness and food policy interventions to reduce UPF intake for alleviating the population burden of CVD. Key messages • Our study suggests the need for increased efforts to implement population wide strategies on regulating food processing, such as taxation and front of package warning labelling of UPF. • Our study emphasizes UPF’s role in cardiovascular prevention, highlighting the need for nutrition counseling on UPF consumption for those at risk of CVD.

Global Trends and Research Collaborations on Food and Beverages Warning Labels: A Bibliometric Analysis

Background: Non-communicable diseases (NCDs) represent a global health challenge, accounting for 74% of deaths worldwide. One of the recommended interventions to reduce the risk of NCDs is the implementation of warning labels (WLs) on food products to alert consumers about high levels of undesirable nutrients, such as sugar or saturated fats. We aimed to conduct a bibliometric analysis of scientific literature related to WL policies in food and beverages to evaluate global trends and collaborations. Methods: A bibliometric analysis was performed using the Web of Science Core Collection (WoSCC). Articles published between 1998 and 2023 were retrieved using the search terms “warning labels” AND “food” OR “beverage”. Bibliometric indicators, including publication counts, citations, collaborations, and thematic trends, were analyzed using the Bibliometrix package in R and VOSviewer. Results: We included 255 articles on WLs. Scientific production increased markedly from 2018 onwards, with over 30 articles published annually from 2018 to 2023. The most cited article, by Taillie et al., focused on the impact of Chile’s WL policies. The United States had the largest scientific production, followed by Brazil and Chile. Nutrients was the journal with the most publications on this topic. Conclusions: The growth in WL-related research, particularly in Latin America, reflects the increasing implementation of these policies. These results underscore key collaborations and evolving research themes, from food labeling to broader public health impacts, emphasizing the need for continued evaluation of WL effectiveness.

U.S. Surgeon General Recommends Warning Labels on Social Media Platforms

U.S. Surgeon General Recommends Warning Labels on Social Media Platforms

“Warning: ultra-processed”: an online experiment examining the impact of ultra-processed warning labels on consumers’ product perceptions and behavioral intentions

BackgroundNutrient content and degree of processing are complementary but distinct concepts, and a growing body of evidence shows that ultra-processed foods (UPFs) can have detrimental health effects independently from nutrient content. 10 + countries currently mandate front-of-package labels (FOPL) to inform consumers when products are high in added sugars, saturated fat, and/or sodium. Public health advocates have been calling for the addition of ultra-processed warning labels to these FOPLs, but the extent to which consumers would understand and be influenced by such labels remains unknown. We examined whether the addition of ultra-processed warning labels to existing nutrient warning labels could influence consumers’ product perceptions and purchase intentions.MethodsIn 2023, a sample of adults in Brazil (n = 1,004) answered an open-ended question about the meaning of the term “ultra-processed,” followed by an online experiment where they saw four ultra-processed products carrying warning labels. Participants were randomly assigned to view either only nutrient warning labels or nutrient plus ultra-processed warning labels. Participants then answered questions about their intentions to purchase the products, product perceptions, and perceived label effectiveness.ResultsMost participants (69%) exhibited a moderate understanding of the term “ultra-processed” prior to the experiment. The addition of an ultra-processed warning label led to a higher share of participants who correctly identified the products as UPFs compared to nutrient warning labels alone (Cohen’s d = 0.16, p = 0.02). However, the addition of the ultra-processed warning label did not significantly influence purchase intentions, product healthfulness perceptions, or perceived label effectiveness compared to nutrient warning labels alone (all p > 0.05). In exploratory analyses, demographic characteristics and prior understanding of the concept of UPF did not moderate the effect of ultra-processed warning labels.ConclusionsUltra-processed warning labels may help consumers better identify UPFs, although they do not seem to influence behavioral intentions and product perceptions beyond the influence already exerted by nutrient warning labels. Future research should examine how ultra-processed warning labels would work for products that do and do not require nutrient warnings, as well as examine the benefits of labeling approaches that signal the health effects of UPFs.Trial registrationClinicalTrials.gov, NCT05842460. Prospectively registered March 15th, 2023.

Food Industry Compliance With the Display of Front-of-Package Warning Labels at the Final Phase (2020) of Chile's Labeling and Advertising Law.

Objectives. To investigate food industry compliance with the display of front-of-package warning labels (FOPLs) on products that exceed regulatory thresholds for being high in calories, added sugars, sodium, or saturated fats after full implementation of Chile's Food Labeling and Advertising Law. Methods. In 2020, trained dietitians took pictures of nutritional information and FOPLs on packaged products in supermarkets. We categorized foods and beverages as requiring FOPLs (or not) using their nutritional composition and ingredients as set out in government guidelines. We compared these classifications with the actual display of FOPLs. Results. About 62.5% of packaged foods and beverages displayed any FOPL. The most frequent label was for energy (38.7%), followed by sugars (35.2%), saturated fats (26.2%), and sodium (22.6%). Compliance with FOPL display was high (93.6% for any "high-in" designation). Lower compliance was observed in nonsausage meat products (83.5%) and soups (84.5%). Candies and sweet confectionery and sausages contributed most to noncompliance with any "high-in" designation. Conclusions. Following the law's full implementation, the food industry complied with the display of FOPLs. Mandatory policies with clear guidelines and monitoring systems can contribute to ensuring and sustaining high compliance. (Am J Public Health. Published online ahead of print September 26, 2024:e1-e8. https://doi.org/10.2105/AJPH.2024.307843).

Delayed effects of cigarette graphic warning labels on smoking behavior.

Graphic warning labels (GWLs) are widely employed to communicate smoking-related health risks; however, their implementation in the US has been held back by concerns about their efficacy. Most GWLs elicit a high level of emotional reaction (ER). The extent to which ER contributes to GWLs efficacy in improving smoking outcomes is a subject of debate. Our recent study showed poorer efficacy of the high-ER GWLs versus the low-ER ones during a month-long naturalistic exposure. Whether GWL effects persist after discontinuing the exposure remains unclear. We conducted a secondary analysis to investigate the delayed effects of GWLs on smoking severity in adult smokers. The number of cigarettes smoked per day (CPD) was measured immediately as well as 4 weeks after the end of a month-long exposure to high-ER versus low-ER GWLs. Participants indicated their subjective feeling of being relieved from having to see the GWLs. We found a significant reduction in CPD from the immediate to the 4-week post-exposure timepoint. There was no difference in CPD reduction between the high-ER and low-ER groups.Subjective sense of relief from GWL exposure was associated with greater CPD reduction in the high-ER group, but not the low-ER group. Our study suggests lasting impact of GWLs on smoking behavior. The findings may be particularly important to high-arousal GWLs, which appear less effective in reducing smoking during active exposure. Whether GWLs that evoke higher ER are more effective remains inconclusive. We recently showed that high-ER GWLs are less effective than low-ER ones in reducing smoking during continuous exposure. Here, we found evidence of delayed GWL effects such that smoking decreased from immediately to four weeks after the end of GWL exposure. Feeling of relief from GWL exposure was associated greater smoking reduction in the high-ER group. We suggest that continuously exposing smokers to high-ER GWLs that have been well remembered may be unnecessary and counterproductive.

Relative efficacy of cigarillo warning statements in text and pictorial formats: An experimental study among a sample of US young adults.

Health warning labels (HWLs) communicate the health risks of cigar use and can decrease use when on cigar packages. This study assessed the relative efficacy of six FDA-proposed individual warning statements in text and pictorial format. A sample of young adults (ages 18-29) were randomized to a text or pictorial warning condition on generic cigarillo packages. The warning statements were about lung cancer and heart disease; cancers of the mouth and throat; secondhand smoke; not a safe alternative; nicotine/addiction; and harm to baby. Negative emotional reactions, cognitive elaboration, and perceived message effectiveness (PME) were assessed for each warning using linear mixed models. Of the 661 participants, 47.3% reported ever cigarillo smoking, 32.7% current smoking, and 20% were susceptible. In the pictorial format, cancers of the mouth and throat elicited lower levels of anxiety compared to secondhand smoke, not a safe alternative, nicotine/addiction, and harm to baby (ps<0.001). Pictorial HWLs with human imagery induced high anxiety, sadness, fear, and guilt reactions (p<0.001) and higher PME (p=0.011) compared to pictorial HWLs with diseased body parts. Compared to the text HWL cancers of the mouth and throat, the text HWL harm to baby elicited higher anxiety (p=0.003), sadness (p=0.002) and PME (p<0.001). Pictorial HWLs depicting people or human imagery, rather than images of diseased organs or body parts, to represent health effects elicited the most negative emotional reactions, such as anxiety and guilt, and higher PME. Including such images and texts highlighting effects on vulnerable populations like babies can better communicate cigarillo health risks, aiming to curb cigarillo use among young people. The study suggests that pictorial health warning labels (HWLs) with human imagery significantly enhance the communication of cigarillo smoking risks compared to images of diseased organs. These HWLs evoke stronger emotional responses, particularly anxiety and guilt, and higher perceived message effectiveness by depicting a recognizable person. Furthermore, text-only warnings describing the smoking effect on vulnerable populations such as babies might have a higher impact on young adults. This evidence supports a strategic shift in FDA policies to include such impactful images and texts, which could potentially lead to a significant reduction in cigarillo use among young people. Our findings underscore the urgent need for continued research and implementation of these enhanced warning labels to improve public health outcomes.

Association Between Cigarette and Bidi Purchase Behavior (Loose vs Pack) and Health Warning Label Exposure: Findings From the Tobacco Control Policy India Survey and In-Depth Interviews With People Who Smoke.

The sale of loose cigarettes or bidis can undermine the purpose of requiring health warning labels (HWLs) on cigarette packs and bidi bundles by diminishing their visibility and legibility. This mixed-methods study aims to examine the association between purchase behavior (loose vs pack or bundle), HWL exposure, and responses to HWLs among Indian adults who smoke. Data were analyzed from the 2018-2019 India Tobacco Control Policy Survey and from 28 in-depth interviews conducted with Indian adults who smoked in 2022. The Tobacco Control Policy Survey sample included tobacco users who bought cigarettes (n=643) or bidis (n=730), either loose or in packs or bundles at their last purchase. Ordinal regression models were fit separately for cigarettes and bidis, whereby HWL variables (noticing HWLs, reading and looking closely at HWLs, forgoing a cigarette or bidi because of HWLs, thinking about health risks of smoking, and thinking about quitting smoking cigarettes or bidis because of HWLs) were regressed on last purchase (loose vs packs or bundles). In-depth interviews with participants from Delhi and Mumbai who purchased loose cigarettes in the last month were conducted, and thematic analysis was used to analyze the interview data. Survey findings indicated that about 74.3% (478/643) of cigarette users and 11.8% (86/730) of bidi users reported having bought loose sticks at their last purchase. Those who purchased loose cigarettes (vs packs) noticed HWLs less often (estimate -0.830, 95% CI -1.197 to -0.463, P<.001), whereas those who purchased loose bidis (vs bundles) read and looked closely at HWLs (estimate 0.646, 95% CI 0.013-1.279, P=.046), thought about the harms of bidi smoking (estimate 1.200, 95% CI 0.597-1.802, P<.001), and thought about quitting bidi smoking (estimate 0.871, 95% CI 0.282-1.461, P=.004) more often. Interview findings indicated lower exposure to HWLs among those who purchased loose cigarettes, primarily due to vendors distributing loose cigarettes without showing the original cigarette pack, storing them in separate containers, and consumers' preference for foreign-made cigarette brands, which often lack HWLs. While participants were generally aware of the contents of HWLs, many deliberately avoided them when purchasing loose cigarettes. In addition, they believed that loose cigarette purchases reduced the HWLs' potential to deliver consistent reminders about the harmful effects of cigarette smoking due to reduced exposure, an effect more common among those who purchased packs. Participants also noted that vendors, especially small ones, did not display statutory health warnings at their point of sale, further limiting exposure to warning messages. Survey and interview findings indicated that those who purchased loose cigarettes noticed HWLs less often. Loose purchases likely decrease the frequency of exposure to HWLs' reminders about the harmful effects of smoking, potentially reducing the effectiveness of HWLs.

Noticing health warning labels and intentions to quit smokeless tobacco products: results from two Global Adult Tobacco Survey rounds, India

Introduction: Health warning labels (HWLs) are one of the key strategies for tobacco control. The current study assessed the individual characteristics affecting the noticeability of HWLs and the thought of quitting smokeless tobacco (SLT) on noticing HWLs. We further estimated the temporal changes in noticeability and thought of quitting after noticing HWLs over time in India. Methods: Data from two rounds (2009–2010 and 2016–2017) of GATS (Global Adult Tobacco Survey) from India were analysed to understand the pattern of SLT usage and estimate the relative changes in the noticeability of HWLs and the thought of quitting SLT among those who noticed HWLs. Sampling weights were used during the analysis. Multivariate binary logistic regression was used to explore the determinants for the noticeability of HWLs and encourage the intention to quit SLT after noticing the HWLs. Results: About 25.9% and 20.6% of participants consumed SLT daily or non-daily in two rounds of GATS. Overall, there was a 14% relative increase in noticing the HWLs and a 20% increase in the thought of quitting in GATS-2 compared with GATS-1. The adjusted odds ratio of observing HWLs among SLT users was 1.51 times (95% confidence interval (CI), 1.44–1.58) in round 2 compared with round 1, while the odds ratio concerning the thought of quitting SLT after noticing HWLs was 1.95 times (95% CI, 1.84–2.06) in round 2 compared with round 1. Conclusions: We observe a consistent increase in the noticeability of HWLs and intentions to quit in SLT users, with significant variations across socio-demographic characteristics calling for concerted efforts. SLT being the major form of tobacco usage in India and Asian countries, HWLs alone cannot bring down the consumption rates, and it needs to be supported by strict implementation of SLT legislation for long-lasting impact.

Alcohol-related cancer risk awareness and support for cancer warning labelling among adults in Estonia

ObjectivesThe aim of this study was to describe alcohol-related cancer risk awareness and examine sociodemographic and alcohol-related variance in attitudes towards implementation of cancer warning labelling on alcohol containers in Estonia. Study designNationally representative data from a 2022 cross-sectional survey (n = 2059) among the 15–74-year-old population in Estonia were used. MethodsDescriptive statistics on the prevalence of alcohol-related cancer risk awareness and support for the implementation of cancer risk warning labelling on alcohol containers are presented. Poisson regression analysis was used to investigate whether support for warning labelling varied by sociodemographic variables, individual alcohol consumption and cancer risk awareness indicators. ResultsStudy found that 73.2% of respondents associated alcohol consumption with increased cancer risk for one or more cancer sites, but implementation of alcohol cancer risk labelling was only supported by 54%. Women, younger age groups, non-Estonians and those with lower education level expressed higher support for warning labelling, whereas lower support was found among those with high-risk alcohol consumption. As expected, awareness of alcohol-related cancer risk and perceiving individual alcohol consumption as a cancer hazard were associated with support for warning labelling. ConclusionsThese findings emphasise the need for better communication of alcohol-related cancer risks as public awareness on the link between alcohol consumption and site-specific cancer risk was low. Increased awareness of alcohol as a cancer risk factor would potentially build public support for introducing cancer-risk warning labelling on containers of alcoholic drinks.

Forced Adoption of Innovations: The Case of Consumer Behavior with Food Warning Labels in Mexico

On March 27, 2020, an amendment to the Official Mexican Standard NOM-051 was published in the Official Gazette of the Federation. The amendment addresses general labeling specifications for food and non-alcoholic beverages. The new regulation introduces three significant changes, which came into force on October 1, 2020. These are warning labeling, nutrient profile, and persuasive elements on the packaging. This study assesses the impact of the regulation on the consumer at three levels: the extent to which consumers understand the five labels, their perception of the image of the product categories and companies, and the potential for shifts in consumption patterns. Similar regulations have been implemented in some other Latin American countries, such as Chile and Ecuador, but the results thus far are inconclusive concerning the actual impact of a long-term change in consumer behavior. With respect to studies conducted in Mexico, this research represents a pioneering investigation into the subject matter. A survey comprising 14 questions was administered, to elucidate the respondents' perceptions and attitudes. The survey was conducted online through convenience sampling with the Google Forms tool. The study was conducted on a sample of 210 individuals, comprising both male and female participants aged 18 and above, who were consumers of mass-produced products that were subject to the provisions of NOM-051. The findings indicate that the majority of respondents lacked clarity regarding the significance of the five black labels on the packaging. Furthermore, the new regulation did not exert a considerable influence on their consumption of processed foods and non-alcoholic beverages. It is anticipated that this research will serve as a reference for companies, government entities, marketing professionals, academics, and all those with an interest in the subject, given that it demonstrates notable findings in several aspects of the regulation's implementation, slightly over a year after its enactment, and the consequences it has had on Mexican consumers and their consumption habits.

Health Warnings on Instagram Advertisements for Synthetic Nicotine E-Cigarettes and Engagement

Synthetic nicotine is increasingly used in e-cigarette liquids along with flavors to appeal to youths. Regulatory loopholes have allowed tobacco manufacturers to use social media to target youths. To analyze the extent to which synthetic nicotine e-cigarette brands have implemented US Food and Drug Administration (FDA) health warning requirements and to evaluate the association between health warnings and user engagement on Instagram. In this cross-sectional study, posts from 25 brands were analyzed across a 14-month period (August 2021 to October 2022). A content analysis was paired with Warning Label Multi-Layer Image Identification, a computer vision algorithm designed to detect the presence of health warnings and whether the detected health warning complied with FDA guidelines by (1) appearing on the upper portion of the advertisement and (2) occupying at least 20% of the advertisement's area. Data analysis was performed from March to June 2024. Synthetic nicotine e-cigarette advertisement on Instagram. The outcome variables were user engagement (number of likes and comments). Negative binomial regression analyses were used to evaluate the association between the presence and characteristics of health warnings and user engagement. Of a total of 2071 posts, only 263 (13%) complied with both FDA health warning requirements. Among 924 posts with health warnings, 732 (79%) displayed warnings in the upper image portion, and 270 (29%) had a warning covering at least 20% of the pixel area. Posts with warnings received fewer comments than posts without warnings (mean [SD], 1.8 [2.5] vs 5.4 [11.7] comments; adjusted incident rate ratio [aIRR], 0.70; 95% CI, 0.57-0.86; P < .001). For posts containing warnings, a larger percentage of the warning label's pixel area was associated with fewer comments (aIRR, 0.96; 95% CI, 0.93-0.99; P = .003). Flavored posts with health warnings placed in the upper image portion received more likes than posts with warnings in the lower portion (mean [SD], 34.6 [35.2] vs 19.9 [19.2] likes; aIRR, 1.48; 95% CI, 1.07-2.06; P = .02). In this cross-sectional study of synthetic nicotine brand Instagram accounts, 87% of sampled posts did not adhere to FDA health warning requirements in tobacco promotions. Enforcement of FDA compliant health warnings on social media may reduce youth engagement with tobacco marketing.

Fact-checker warning labels are effective even for those who distrust fact-checkers.

Warning labels from professional fact-checkers are one of the most widely used interventions against online misinformation. But are fact-checker warning labels effective for those who distrust fact-checkers? Here, in a first correlational study (N = 1,000), we validate a measure of trust in fact-checkers. Next, we conduct meta-analyses across 21 experiments (total N = 14,133) in which participants evaluated true and false news posts and were randomized to either see no warning labels or to see warning labels on a high proportion of the false posts. Warning labels were on average effective at reducing belief in (27.6% reduction), and sharing of (24.7% reduction), false headlines. While warning effects were smaller for participants with less trust in fact-checkers, warning labels nonetheless significantly reduced belief in (12.9% reduction), and sharing of (16.7% reduction), false news even for those most distrusting of fact-checkers. These results suggest that fact-checker warning labels are a broadly effective tool for combatting misinformation.

Tobacco Control Policy in India: Progress and Challenges Quantified Using the Tobacco Control Scale.

One of the most vexing challenges to public health today is the menace of tobacco. Despite the large body of evidence indicating the vast scale of health hazards, tobacco use continues to be a major cause of preventable death. This study was conducted with the objective of quantifying the progress and challenges of the tobacco control policy of India. The Tobacco Control Scale (TCS) was used, which has a maximum score of 100 and assesses nine components including, price of cigarettes, smoke-free public and work places, spending on public information campaigns, comprehensive bans on advertising and promotion, large pictorial health warning labels, treatment to help smokers stop, illicit tobacco trade, tobacco industry interference and ratification of the WHO FCTC. The components of the TCS for India were scored based on data obtained from the WHO, Report on The Global Tobacco Epidemic, 2021 and the Cigarettes and Other Tobacco Products Act 2003 and their amendments and the Tobacco India 2023 country profile. The total score for the tobacco control scale placed India at 65 points, scoring highest with respect to 'large pictorial health warning labels', and lower with respect to 'spending on public information campaigns', 'illicit tobacco trade' and 'price of cigarettes'. Strong tobacco control legislation and its equally robust implementation is an affirmative step in achieving the vision of the WHO-FCTC and empowering the world towards being tobacco free.

95 - Mitigating unintended consequences: Evaluating combined sugar and sweetener warning labels on beverage choices in a real-world selection task

95 - Mitigating unintended consequences: Evaluating combined sugar and sweetener warning labels on beverage choices in a real-world selection task

Five years of discourse related to Indonesia tobacco control reform: a content analysis of online media coverage

BackgroundIn 2017, Indonesia initiated the amendment of its 11-year-old tobacco control regulation (PP 109/2012) to reduce smoking among youth, but the process was stalled. The proposed changes in the regulation...

Differences in Presenting Health Warning Labels on Hookah Venue Menus Between Immersive Virtual Reality and Online Surveys

Background Virtual reality (VR) platforms can simulate the real world, whereas online surveys are efficient settings for assessing and testing information. In this study, the effects of presenting health warning labels (HWLs) on hookah venue menus were compared between these two message-testing settings. Methods Separate studies were conducted in VR (n = 96) and online survey (n = 213) settings. Participants in both studies were randomly assigned to view menus with or without HWLs. This secondary data analysis compared outcomes between settings after propensity score weighting to account for differences in age, race, marital status, and education between studies. Results Significant between-study differences were noted for the effects of HWLs on people’s perceptions of the absolute harm of hookah smoking (p = 0.0363), the relative harm of hookah compared to cigarettes (p < 0.001), the absolute addictiveness of hookah (p < 0.001), and the relative addictiveness of hookah compared to cigarettes (p = 0.0352). When outcome variables differed significantly between the HWL and control conditions in only one of the two studies, smaller p-values were identified for the online survey setting than for the VR setting. Conclusions This study represents the first direct comparison of the effects of hookah HWLs between two message-testing settings. HWLs tested in the online survey setting were associated with larger shifts in attitudes and beliefs than those tested in the VR setting, suggesting that the effectiveness of hookah HWLs on attitudes and beliefs may be moderated by the message-testing platform. Additional real-world experiments remain necessary to determine whether either setting can accurately assess the effectiveness of HWLs.

Examining the Effects of Social Media Warning Labels on Perceived Credibility and Intent to Engage with Health Misinformation: The Moderating Role of Vaccine Hesitancy

Despite the robust scientific evidence affirming the safety and efficacy of COVID-19 vaccines, the proliferation of misinformation on social media platforms poses a threat by potentially exacerbating vaccine hesitancy. In response, certain social media platforms have taken measures to flag posts containing such misinformation with warning labels, aiming to dispel false beliefs. This present study employs a survey experiment (N = 304) to examine the effectiveness of two distinct warning labels – disputed and neutral warning labels – in the Twitter (the social media platform now known as X) context, specifically targeting misinformation about COVID-19 vaccines. This study investigates the nuanced effects of vaccine hesitancy on the perceived credibility of debunked misinformation posts following the application of warning flags. The results demonstrated that disputed labels significantly reduced the perceived credibility of misinformation regarding anti-COVID-19 vaccines in comparison to posts without any labeling. Nevertheless, individuals exhibiting higher levels of vaccine hesitancy tended to view the misinformation as more credible than their counterparts with lower levels of hesitancy. These findings present the efficacy of warning labels in combatting misinformation on social media platforms, particularly among those who are least hesitant about vaccination.

Thermochromic structural color based on pressure storage-release toward emerging applications

Conventional thermochromic photonic crystal (TPC) hydrogels and liquids have gained prominence due to their unique capability of adjusting their colors by temperature (T). However, challenges including non-recordable structural colors, poor stability, and limited color tunability significantly limit their advanced applications. To address these issues, a versatile pressure-stored TPC (PSTPC) with repeatable fixable compressed non-close-packing structures has been fabricated based on combining phase-changing materials and elastic photonic crystals. Distinguishing from conventional TPCs, PSTPCs possess 1) recordable colors with excellent stability under normal conditions; 2) adjustable colors from red to blue by simply altering storable pressure; and 3) a T-triggered color change by releasing the pressure. These PSTPCs have been experimentally proved to be ideal candidates for various applications, including hot warning labels, ink-free rewritable papers, and elaborate anti-counterfeiting tags. This work offers a new perspective for designing and fabricating combined materials-based stimulus-responsive structural color materials with advanced multifunctional applications.