Search results
Found 23087 matches for
We lead multidisciplinary applied research and training to rethink the way health care is delivered in general practice and across the community.
Combining positioning and labelling interventions for healthier and more environmentally sustainable products: A randomised controlled trial in an online experimental supermarket.
Population diets need to become healthier and more sustainable to limit their negative effects on health and environment. This study assessed the effect of a positioning intervention, in isolation and in combination with a labelling intervention, on the a) healthiness and b) environmental sustainability of food choices in an experimental online supermarket. Participants (n=2220) were randomly assigned to one of five trials groups (control; healthier items shown earlier ("health position"); health position & nutri-score labels; environmentally sustainable products shown earlier ("eco position"); eco position & ecolabels) and completed a shopping task in an experimental online supermarket. Linear regressions showed that compared to control, mean scaled nutri-scores of shopping baskets were significantly lower (healthier) for health position (-2.30; 95%CI: -3.07, -1.52) and health position & labels (-2.50; 95%CI: -3.28, -1.72), with no significant difference between health position and health position & labels (-0.20; 95%CI: -0.66, 0.25). The mean eco scores of shopping baskets were significantly reduced (more sustainable) for eco position (-24%; 95%CIs: -15%, -31%)) and eco position & labels (-30%; 95% CIs: -22%, 37%).) compared to control. The eco position & labels group had significantly lower mean eco scores (-8%; 95% CIs: -2%, -14%) compared to eco position. The positioning intervention improved health and environmental sustainability of food selections in an experimental online supermarket, with less robust evidence for a small additional effect of adding labels. There was no suggestion that adding labels that potentially make the positioning intervention more salient had any backfire effects.
Effects of brand-matched alcoholic and alcohol-free and low-alcohol drinks adverts on drink selections: A United Kingdom-based randomised controlled trial in an experimental online supermarket
Background and aims: Restricting alcohol advertising may reduce alcohol consumption and related ill-health. However, advertisements for alcohol-free and low-alcohol drinks (NoLos) with brand-matched alcoholic versions are typically exempt from restrictions, which could lead to surrogate marketing (adverts for NoLo beverages also promoting brand-matched alcoholic options). This study measured the impact of advertisements for brand-matched NoLo beverages on product selections in a simulated online supermarket, in the UK. Design, setting, participants and intervention: We conducted a randomised controlled trial with 1638 UK regular alcohol consumers (aged 18–91), assigned to one of three groups: (1) alcohol adverts (n = 469), where participants viewed an advertisement (embedded within a video) for one of four alcoholic beverages; (2) NoLo adverts (n = 472), for one of four brand-matched NoLo beverages; and (3) unrelated adverts (n = 697), for batteries. Participants then selected food and drinks for a barbecue in a simulated online supermarket. Measurements: We collected data on products selected in the simulated online supermarket (e.g. product name, category, quantity, energy). Risk of alcohol dependence was measured using the Alcohol Use Disorder Identification Test Consumption Questions (AUDIT-C). The primary outcome was selection (yes/no) of advertised alcoholic and NoLo products. Secondary outcomes included the selection (yes/no) of any alcoholic or NoLo products. We also examined the recall of advertised brands and products through survey questions. Findings: Viewing NoLo, but not alcohol, advertisements statistically significantly increased the odds of selecting the advertised products, compared with unrelated advertisements [alcohol group: odds ratio (OR) = 1.62, 95% confidence interval (CI) = 1.03–2.53, Benjamini-Hochberg-adjusted P = 0.11; NoLo group: OR = 2.18, 95% CI = 1.24–3.91, Benjamini-Hochberg-adjusted P = 0.022]. Although the odds of selecting the alcoholic version of the advertised product were higher in those exposed to NoLo adverts vs. control (OR = 1.48, 95% CI = 0.94–2.33, Benjamini-Hochberg-adjusted P = 0.13), this association did not reach statistical significance. Fifty-nine percent of participants in all three groups recalled the advertised brand. Among those who remembered the brand of advertisement, 96% in the alcohol group also correctly recalled the advertised product, while 44% in the NoLo group reported seeing an advert for the alcoholic version of the product (X2 = 297.16, P < 0.001, df = 2). Conclusions: Exposure to advertisements for brand-matched alcohol-free and low-alcohol drinks increases brand (over product) recall, but, while the direction of effects is consistent with these advertisements promoting the selection of alcoholic beverages, evidence of the impact on alcohol selection is inconclusive.
Population-level interventions for sustainable food consumption
Population-level interventions are directed at an entire population, in contrast to individual-level interventions, which target selected groups (e.g., skills training programs directed towards high-risk individuals). As they are delivered across whole populations—or population groups—they can have considerably more reach than individual-level interventions. As everyone in a population stands to benefit from the intervention, population interventions have the potential to be more equitable than individual-level interventions. We discuss some of the approaches that can be used to conceptualize population-level interventions: the Nuffield intervention ladder, the COM-B model, analysis grid for environments linked to obesity, and typology of interventions in physical proximal microenvironments (TIPPME) frameworks. We then move onto discussing the evidence base of different population-level interventions for reducing meat consumption and shifting to more plant-based diets.
Ethnic differences in meat consumption attitudes, norms and behaviors: A survey of White, South Asian and Black ethnic groups in the UK
A reduction in meat consumption is necessary to mitigate negative impacts of climate change and adverse health outcomes. The UK has an increasingly multi-ethnic population, yet there is little research on meat consumption habits and attitudes among ethnic groups in the UK. We ran a survey (N = 1014) with quota samples for ethnic groups and analyzed attitudes, behaviors and norm perceptions of White, South Asian and Black British respondents. Most respondents believe overconsumption of red and processed meat has negative impacts on health (73.3%) and the environment (64.3%).South Asian respondents were statistically significantly less likely to be meat eaters than White respondents (OR = 0.44, 95% CIs: 0.30-0.65, t = −4.15, p = 0.000), while there was no significant difference between White and Black respondents (OR = 1.06, 95% CIs: 0.63–1.76, t = 0.21, p = 0.834). Both South Asian (OR = 2.76, 95% CIs: 1.89–4.03 t = 5.25, p = 0.000) and Black respondents (OR = 2.09, 95% CIs: 0.1.30–3.35, t = 3.06, p = 0.002) were significantly more likely to express being influenced by friends and family in their food choices than White respondents. South Asian (OR = 3.24,95% CIs: 2.17–4.84, t = 5.74, p = 0.000) and Black (OR = 2.02,95% CIs: 1.21–3.39, t = 2.69, p = 0.007) respondents were also both significantly more likely to report they would want to eat similarly to their friends and family than White respondents. Statistical analyses suggested some gender and socioeconomic differences across and among ethnic groups, which are reported and discussed. The differences in meat consumption behaviors and norm conformity between ethnic groups raises the prospect that interventions that leverage social norms may be more effective in South Asian groups than Black and White groups in the UK.
Perceptions of social norms around healthy and environmentally-friendly food choices: Linking the role of referent groups to behavior
Referent groups can moderate the perception of social norms and individuals’ likelihood to model these norms in food choice contexts, including vegetable intake and reduced meat consumption. The present study investigated whether having a close vs. a distant social group as the referent changed perceptions of social norms around making healthy and eco-friendly food choices. It also assessed whether these changes were associated with a difference in the health and environmental impacts of food choice in a virtual grocery shopping task. A nationally representative sample of UK adults (N = 2,488) reported their perceptions of making healthy and eco-friendly food choices being the norm among people they share meals with (close referent group) and most people in the UK (distant referent group). The former was more commonly perceived to be making both healthy (Z = −12.0, p < 0.001) and eco-friendly (Z = −13.27, p < 0.001) food choices than the latter. Perceptions of norms referring to the close group were significantly associated with the environmental (β = −0.90, 95% CIs: −1.49, −0.28) and health (β = −0.38 p < 0.05, 95% CIs: −0.68, −0.08) impacts of participants’ food choices in a virtual shopping task. No such relationship was found for norms referring to the distant group for both environmental (β =0.43, p > 0.05, 95% CIs: −1.12, 0.25) and health (β = −0.06, p > 0.05, 95% CIs: −0.37, 0.25) impacts. Framing social norms around making healthy and eco-friendly food choices to refer to a close referent group may change their perceptions and ability to encourage sustainable and healthy food purchasing.
A dynamic social norm messaging intervention to reduce meat consumption: A randomized cross-over trial in retail store restaurants
Perceptions of social norms around eating behavior can influence food choices. Communicating information about how others are changing their eating behavior over time (dynamic descriptive social norms) may motivate individuals to change their own food selection and consumption. Following a four-week baseline period, 22 in-store restaurants of a major retail chain across the UK were randomized to display a dynamic descriptive social norm message intended to motivate a shift from meat-to plant-based meals either during the first two, or last two weeks of the four-week study period. A linear regression model showed there was no evidence of an effect of the intervention (β = -0.022, p = .978, 95% CIs: −1.63, 1.58) on the percentage sales of meat- vs plant-based dishes. Fidelity checks indicated that adherence to the intervention procedure was often low, with inconsistencies in the placement and display of the intervention message. In four stores with high fidelity the estimated impact of the intervention was not materially different. The lack of apparent effectiveness of the intervention may reflect poor efficacy of the intervention or limitations in its implementation in a complex food purchasing environment. The challenges highlighted by this study should be considered in future design and evaluation of field trials in real-world settings.
Testing the effect of ecolabels on the environmental impact of food purchases in worksite cafeterias: a randomised controlled trial
Background: Reducing the environmental impact of foods consumed is important for meeting climate goals. We aimed to conduct a randomised controlled trial to test whether ecolabels reduce the environmental impact of food selected in worksite cafeterias, alone or in combination with increased availability of more sustainable meal options. Methods: Worksite cafeterias (n = 96) were randomised to one of three study groups, with 54 included for final analysis. One group was intended to increase the availability of meat-free options, but no change was implemented. Therefore, this group was treated as part of the control, creating two groups: (1) control (no ecolabels) (n = 35), and (2) ecolabels (n = 19). Regression analysis assessed the primary outcome of total environmental impact of hot meals sold over a 6-week period. Secondary outcome analyses explored the individual environmental indicators that composed the total environmental impact score (i.e., greenhouse gas emissions, biodiversity loss, eutrophication, and water scarcity). The mean weekly environmental impact scores of hot meal options over the full 12-week trial period were assessed using hierarchical mixed effects models. Results: There was no significant effect of the intervention on the environmental impact scores of meals sold (mean difference between control and intervention sites: -1.4%, 95%CI: -33.6%, + 30.8%). There was no evidence of an effect in mean weekly environmental impact score (-5.4%, 95%CI: -12.6%, + 2.5%), nor in any of the four individual environmental indicators (greenhouse gas emissions: -3.6%, 95%CI: -30.7%, 34.3%; biodiversity loss: 2.0%, 95%CI: -25.8%, 40.2%; eutrophication: -2.4%, 95%CI: -29.3%, 34.7%; water scarcity: -0.4%, 95%CI: -28.7%, 39.1%). Conclusions: Ecolabels may not be an effective tool to shift consumer behaviour in worksite cafeterias towards meals with lower environmental impact. Trial registration: The study was pre-registered prospectively on ISRCTN (https://www.isrctn.com/ISRCTN10268258; 06/01/2022).
Impact of increasing the relative availability of meat-free options on food selection: two natural field experiments and an online randomised trial
Background: Increasing the availability of lower energy-density foods is a promising intervention to encourage healthier food purchasing but few studies have examined the effect of increasing availability of meat-free meals to promote more sustainable purchasing. We report three studies, all examining the impact of altering the availability of meat-free meals on meal selection. Methods: Study 1 (a natural experiment in one university cafeteria) examined the impact of altering the ratio of meat-free meals (one meat-free and two meat, to two meat-free and one meat) on weekly sales of meals containing meat. Study 2 (a natural experiment in 18 worksite cafeterias) examined the impact on meat-free meal sales of a menu change designed to increase the availability of meat-free meals. Study 3 (an online study of 2205 UK-representative adults) compared meal selections when participants were randomised to ranges comprised of (a) one meat-free, three meat options; (b) two meat-free, two meat; or (c) three meat-free, one meat. Results: Study 1 suggested a significant decrease in the proportion of sales of meat options when the availability of meat-free options increased (− 19.9 percentage points; 95%CIs:-25.2,-14.6), with no evidence of changes to meat-based meal sales in other university cafeterias during the same period. Findings from Study 2 were mixed: multilevel regressions found no evidence of an increase in meat-free meals following the menu change (2.3 percentage points; 95%CIs: − 1.3,5.9), while interrupted time-series analyses suggested sales did increase (2.3; 95%CIs: 0.4,4.2), but implementation of the planned change was limited. In Study 3 reducing meat-free options from 50 to 25% reduced participants’ selection of meat-free options (odds ratio 0.35; 95%CIs: 0.26,0.46), while increasing meat-free options from 50 to 75% increased meat-free selections (odds ratio 2.43; 95%CIs: 1.94,3.04). There was no evidence effects were moderated by gender, socioeconomic status or usual meat consumption. Conclusion: Increasing the availability of meat-free options is effective at reducing meat selection and purchasing for different ratios of meat to meat-free options. The magnitude of the effect is uncertain, but with no evidence of differences in response by demographic groups when directly tested. Trial registration: Study 3: Open Science Framework; https://osf.io/ze9c6; 6/8/2020.
Is altering the availability of healthier vs. less-healthy options effective across socioeconomic groups? A mega-analysis
Background: Availability interventions have been hypothesised to make limited demands on conscious processes and, as a result, to be less likely to generate health inequalities than cognitively-oriented interventions. Here we synthesise existing evidence to examine whether the impact of altering the availability of healthier vs. less-healthy options differs by socioeconomic position. Methods: Individual-level data (21,360 observations from 7,375 participants) from six studies (conducted online (n = 4) and in laboratories (n = 2)) were pooled for mega-analysis. Multilevel logistic regressions analysed the impact of altering the availability of healthier options on selection of a healthier (rather than a less-healthy) option by socioeconomic position, assessed by (a) education and (b) income. Results: Participants had over threefold higher odds of selecting a healthier option when the available range was predominantly healthier compared to selections when the range offered was predominantly less-healthy (odds ratio (OR): 3.8; 95%CIs: 3.5, 4.1). Less educated participants were less likely to select healthier options in each availability condition (ORs: 0.75–0.85; all p < 0.005), but there was no evidence of differences in healthier option selection by income. Compared to selections when the range offered was predominantly less-healthy, when predominantly healthier options were available there was a 31% increase in selecting healthier options for the most educated group vs 27% for the least educated. This modest degree of increased responsiveness in the most educated group appeared only to occur when healthier options were predominant. There was no evidence of any differential response to the intervention by income. Conclusion: Increasing the proportion of healthier options available increases the selection of healthier options across socioeconomic positions. Availability interventions may have a slightly larger beneficial effect on those with the highest levels of education in settings when healthier options predominate.
Evaluation of physical activity calorie equivalent (PACE) labels' impact on energy purchased in cafeterias: A stepped-wedge randomised controlled trial
Background Penletamseectoan-fairnmatlhyastisalslhuegagdeinsgteledvethlsaatruerseinprgepsehnytsediccaolrarecctitvlyit:y calorie equivalent (PACE) labels results in people selecting and consuming less energy. However, the meta-analysis included only 1 study in a naturalistic setting, conducted in 4 convenience stores. We therefore aimed to estimate the effect of PACE labels on energy purchased in worksite cafeterias in the context of a randomised study design. Methods and findings A stepped-wedge randomised controlled trial (RCT) was conducted to investigate the effect of PACE labels (which include kcal content and minutes of walking required to expend the energy content of the labelled food) on energy purchased. The setting was 10 worksite cafeterias in England, which were randomised to the order in which they introduced PACE labels on selected food and drinks following a baseline period. There were approximately 19,000 workers employed at the sites, 72% male, with an average age of 40. The study ran for 12 weeks (06 April 2021 to 28 June 2021) with over 250,000 transactions recorded on electronic tills. The primary outcome was total energy (kcal) purchased from intervention items per day. The secondary outcomes were: energy purchased from non-intervention items per day, total energy purchased per day, and revenue. Regression models showed no evidence of an overall effect on energy purchased from intervention items, -1,934 kcals per site per day (95% CI -5,131 to 1,262), p = 0.236, during the intervention relative to baseline, equivalent to -5 kcals per transaction (95% CI -14 to 4). There was also no evidence for an effect on energy purchased from non-intervention items, -5 kcals per site per day (95% CI -513 to 504), p = 0.986, equivalent to 0 kcals per transaction (95% CI -1 to 1), and no clear evidence for total energy purchased -2,899 kcals per site (95% CI -5,810 to 11), p = 0.051, equivalent to -8 kcals per transaction (95% CI -16 to 0). Study limitations include using energy purchased and not energy consumed as the primary outcome and access only to transactionlevel sales, rather than individual-level data. Conclusion Overall, the evidence was consistent with PACE labels not changing energy purchased in worksite cafeterias. There was considerable variation in effects between cafeterias, suggesting important unmeasured moderators.
Acceptability of policies to reduce consumption of red and processed meat: A population-based survey experiment
Policies to reduce meat consumption are needed to help achieve climate change targets, and could also improve population health. Public acceptability can affect the likelihood of policy implementation. This study estimated the acceptability of policies to reduce red and processed meat consumption, and whether acceptability differed when policies were framed as benefitting health or the environment. In an online experiment, 2215 UK adults rated the acceptability of six policies, presented in a randomised order. Prior to rating policies, participants were randomised to one of two framing conditions, with policy outcomes described either as benefitting health or the environment. Regression models examined differences in the primary outcome – policy acceptability (rated on a 7-point scale) – by framing. Labels were the most accepted policy (48% support), followed by a media campaign (45%), reduced availability (40%) and providing incentives (38%). Increasing price (27%) and banning advertising (26%) were the least accepted. A substantial proportion of participants neither supported nor opposed most policies (26–33%), although this fell to 16% for increasing price. There was no evidence that framing policy benefits from a health or environment perspective influenced acceptability (−0.06, 95%CIs: 0.18,0.07). Fewer than half of the UK sample expressed support for any of six policies to reduce meat consumption, regardless of framing measures as benefitting health or the environment. Conversely, fewer than half expressed opposition, with the exception of price, suggesting considerable scope to influence public opinion in support of meat reduction measures to meet environmental and health goals.
Testing the effect of a dynamic descriptive social norm message on meat-free food selection in worksite cafeterias: a randomized controlled trial
Background: Overconsumption of meat is a threat to planetary health. Meat consumption is socially and culturally patterned, and interventions using social norms could be a promising strategy to encourage meat reduction. Methods: We developed and tested the effectiveness of a dynamic descriptive social norm message displayed in worksite cafeterias (N = 25, intervention = 12, control = 13) to increase meat-free meal selection. The message was developed based on existing evidence and in collaboration with the catering company operating the cafeterias. The message communicated a specific change in target behavior, using a relevant and relatable referent group, grounding the desired behavior change in time and place, and included a clear call to action. The social norm messages were displayed in each intervention cafeteria for 8 weeks on free-standing banners, posters, and floor stickers. We compared the change in weekly percentage of meat-free meal sales (measured as number of meals sold) between intervention and control cafeterias through linear mixed-effects models. We conducted fidelity checks in intervention cafeterias and interviewed customers to assess perceptions of the intervention. Results: There was no evidence that the intervention led to an increase in sales of meat-free meals (− 2.22 percentage point change, 95% CIs [− 7.33, 2.90], p = 0.378). Pre-intervention baseline sales of meat-free meals varied by site, but there was no evidence the intervention was differentially effective for sites with higher vs. lower baselines. There was also no evidence that the intervention changed overall meal sales. The intervention was implemented with high fidelity, though out of 155 customers interviewed, 57% reported that they did not notice the messages, and only 2% correctly recalled the message. Conclusions: There was no evidence that empirically informed and co-created dynamic descriptive social norm messages increased selection of meat-free meals in worksite cafeterias. This could be due to low salience of the intervention in a busy, fast-paced environment, or the strength of existing eating habits in a workplace cafeteria. The findings suggest that norm messaging interventions, when delivered as an isolated intervention, may not be effective to change a complex and socially grounded dietary behavior such as meat consumption. Trial registration: OSF Registries, Registered September 23, 2022, https://osf.io/h7zkf
Preventing type 2 diabetes: A research agenda for behavioural science
Aims: The aim of this narrative review was to identify important knowledge gaps in behavioural science relating to type 2 diabetes prevention, to inform future research in the field. Methods: Seven researchers who have published behaviour science research applied to type 2 diabetes prevention independently identified several important gaps in knowledge. They met to discuss these and to generate recommendations to advance research in behavioural science of type 2 diabetes prevention. Results: A total of 21 overlapping recommendations for a research agenda were identified. These covered issues within the following broad categories: (a) evidencing the impact of whole population approaches to type 2 diabetes prevention, (b) understanding the utility of disease-specific approaches to type 2 diabetes prevention such as Diabetes Prevention Programmes (DPPs) compared to generic weight loss programmes, (c) identifying how best to increase reach and engagement of DPPs, whilst avoiding exacerbating inequalities, (d) the need to understand mechanism of DPPs, (e) the need to understand how to increase maintenance of changes as part of or following DPPs, (f) the need to assess the feasibility and effectiveness of alternative approaches to the typical self-regulation approaches that are most commonly used, and (g) the need to address emotional aspects of DPPs, to promote effectiveness and avoid harms. Conclusions: There is a clear role for behavioural science in informing interventions to prevent people from developing type 2 diabetes, based on strong evidence of reach, effectiveness and cost-effectiveness. This review identifies key priorities for research needed to improve existing interventions.
Explaining the effect on food selection of altering availability: two experimental studies on the role of relative preferences
Background: Increasing the availability of healthier or plant-based foods increases their selection. The current studies aimed to examine the extent to which relative preferences account for food selections following availability interventions. In particular, (a) whether increasing the availability of lower-energy options increases the likelihood that individuals’ highest-ranked option is lower-energy, and (b) the extent to which selections reflect individuals’ highest-ranked option from the available range. Methods: UK adults (Study 1: n = 1976; Study 2: n = 1078) took part in within-subjects online studies. In both studies, the order of preference between food options was established by participants choosing the option that they would prefer “to eat right now” from every possible pairing within a pool of eight options. Then, participants were shown either predominantly higher-energy options (three higher- and one lower-energy) or predominantly lower-energy options (vice versa), presented in a random order. Results: When predominantly lower-energy options were presented, the odds of the highest-ranked option being a lower-energy option increased ten-fold (Study 1: odds ratio: 10.1; 95%CI: 8.9,11.4; Study 2: odds ratio: 10.4; 95%CI: 7.4,14.7), compared to when predominantly higher-energy options were available. In both studies, around 90% of selections reflected the highest-ranked option in the range offered in the studied availability conditions (range 88–92%). Conclusions: These studies suggest that increased availability of lower-energy options increases the likelihood of an individual’s highest-ranked option being lower-energy, and that the highest-ranked option has the greatest likelihood of selection. As such, preferences may be a key contributor to the effects of altering availability on food selections. Trial registration: ISRCTN (http://www.isrctn.com/ISRCTN27598623; 3/12/19 [Study 1]; http://www.isrctn.com/ISRCTN61010183; 20/4/20 [Study 2]).
Glassware design and drinking behaviours: a review of impact and mechanisms using a new typology of drinking behaviours
Much of the global burden of disease is attributable to unhealthy behaviour, including excessive consumption of alcohol and sugar-sweetened beverages. Developing effective methods to change these drinking behaviours could inform policies to improve population health. In line with an increasing interest in environmental-level interventions–i.e., changing the environment in which a behaviour occurs in order to change the behaviour of interest–this review first describes the existing evidence of the impact of glassware design (including capacity and shape) on drinking behaviours (e.g., at the ‘micro’ level–including sip size, as well as at the macro level–including amount consumed). The roles of two sets of possible underlying mechanisms–perception and affordance–are also explored. Finally, this review sets out a provisional typology of drinking behaviours to enable more systematic approaches to the study of these behaviours. While there is a paucity of evidence–in particular on measures of consumption–this growing evidence base suggests promising targets for novel interventions involving glassware design to reduce the consumption of drinks that harm health. Trial registration:ISRCTN.org identifier: ISRCTN10456720.
Impact of increasing the availability of healthier vs. less-healthy food on food selection: a randomised laboratory experiment
Background: Environmental cues shape behaviour, but few studies compare the impact of targeting healthier vs. less-healthy cues. One online study suggested greater impact on selection from increasing the number of less-healthy (vs. healthier) snacks. The current study aimed to: (1) extend the previous study by using physically-present snacks for immediate consumption; (2) explore responsiveness by socio-economic position; (3) investigate possible mediators (response inhibition, food appeal) of any socio-economic differences in selection. Methods: In a between-subjects laboratory experiment UK adults (n = 417) were randomised according to their ID number (without blinding) to one of three ranges of options: Two healthier, two less-healthy [“Equal”] (n = 136); Six healthier, two less-healthy [“Increased Healthier”] (n = 143); Two healthier, six less-healthy [“Increased Less-Healthy”] (n = 138). Participants completed measures of response inhibition and food appeal, and selected a snack for immediate consumption from their allocated range. The primary outcome was selection of a healthier (over less-healthy) snack. Results: The odds of selecting a less-healthy snack were 2.9 times higher (95%CIs:1.7,5.1) in the Increased Less-Healthy condition compared to the Equal condition. The odds of selecting a healthier snack were 2.5 times higher (95%CIs:1.5,4.1) in the Increased Healthier (vs. Equal) condition. There was no significant difference in the size of these effects (− 0.2; 95%CIs:-1.1,0.7). Findings were inconclusive with regard to interactions by education, but the direction of effects was consistent with potentially larger impact of the Increased Healthier condition on selection for higher-educated participants, and potentially larger impact of the Increased Less-Healthy condition for less-educated participants. Conclusions: A greater impact from increasing the number of less-healthy (over healthier) foods was not replicated when selecting snacks for immediate consumption: both increased selections of the targeted foods with no evidence of a difference in effectiveness. The observed pattern of results suggested possible differential impact by education, albeit not statistically significant. If replicated in larger studies, this could suggest that removing less-healthy options has the potential to reduce health inequalities due to unhealthier diets. Conversely, adding healthier options could have the potential to increase these inequalities. Trial registration: ISRCTN: ISRCTN34626166; 11/06/2018; Retrospectively registered.