BackgroundGlassware design may affect drinking behaviour for alcoholic beverages, with glass shape and size influencing drinking speed and amount consumed. Uncertainty remains both about the extent to which these effects are restricted to alcohol and the underlying mechanisms. The primary aim of the current study was to examine the effect of differently shaped glasses on time taken to drink a soft drink. The secondary aim was to develop hypotheses about mechanisms concerning micro-drinking behaviours and perceptual effects.MethodIn a single-session experiment, 162 participants were randomised to receive 330ml of carbonated apple juice in a glass that was either inward-sloped, straight-sided, or outward-sloped. The primary outcome measure was total drinking time. Secondary outcome measures included micro-drinking behaviours (sip size, sip duration, interval duration), and perceptual measures (midpoint bias, drink enjoyment).ResultsParticipants drank 21.4% faster from the outward-sloped glass than from the straight-sided glass [95%CI: 0.2%,38.0%] in adjusted models. They were also 18.2% faster from the inward-sloped glass than the straight-sided glass, but this did not reach statistical significance with wide confidence intervals also consistent with slower drinking [95%CI: -3.8%,35.6%]. Larger sips were associated with faster drinking times (Pearson’s r(162) = -.45, p < .001). The direction of effects suggested sips were larger from the outward-sloped and inward-sloped glasses, compared to the straight-sided glass (15.1%, 95%CI: -4.3%,38.0%; 19.4%, 95%CI: -0.5%,43.6%, respectively). There were no significant differences between glasses in mean sip or interval duration. Bias in midpoint estimation was greater for the outward-sloped glass (12.9ml, 95%CI: 6.6ml,19.2ml) than for the straight-sided glass, although the degree of bias was not associated with total drinking time (Pearson’s r(162) = 0.01, p = .87).DiscussionIndividuals drank a soft drink more quickly from an outward-sloped glass, relative to a straight-sided glass. Micro-drinking behaviours, such as sip size, are promising candidates for underlying mechanisms.

Reducing consumption of drinks which contain high levels of sugar and/or alcohol may improve population health. There is increasing interest in health behaviour change approaches which work by changing cues in physical environments ("nudges"). Glassware represents a modifiable cue in the drinking environment that may influence how much we drink. Here, we report three laboratory experiments measuring consumption of soft drinks served in different glasses (straight-sided vs. outward-sloped), using distinct paradigms to measure drinking. In Study 1 (N = 200), though total drinking time was equivalent, participants consumed a soft drink with a more 'decelerated' trajectory from outward-sloped tumblers, characterised by a greater amount consumed in the first half of the drinking episode. In Study 2 (N = 72), during a bogus taste test, participants consumed less from straight-sided wine flutes than outward-sloped martini coupes. In Study 3 (N = 40), using facial electromyography to explore a potential mechanism for decreased consumption, straight-sided glasses elicited more 'pursed' lip embouchures, which may partly explain reduced consumption from these glasses. Using a combination of methods, including objective measures of volume drunk and physiological measures, these findings suggest that switching to straight-sided glasses may be one intervention contributing to the many needed to reduce consumption of health-harming drinks. Overconsumption of drinks containing excess sugars and alcohol is a major threat to population health globally 1-4. Sugary drink consumption, in particular, is linked with a number of health conditions, including Type 2 diabetes, cardiovascular disease, and others 5,6. Developing novel and effective interventions to change drinking behaviour is thus an important goal of research and policy. There is increasing interest in approaches that work by changing cues in physical environments-known also as "nudging" 7-10. Broadly speaking, these interventions are thought to engage automatic (rather than reflective) processes, requiring relatively less active engagement or high-level cognitive processing to elicit a change in behaviour than other types of behaviour change techniques 11. One aspect of the drinking environment that has the potential to influence drinking behaviour-possibly outside of awareness-is the glassware in which drinks are served. There is a growing evidence base for the effect of glass size and shape on drinking behaviours. Wine glass size has increased over the past 300 years-in particular in the last 30 years 12-with some evidence that the use of larger wine glasses increases wine consumed 13-15. The shape of a glass-in particular, whether it is outwardsloped or straight-sided-may also influence consumption. Two studies have explored the impact of glass shape on the total time spent drinking. One study found slower consumption from straight-sided glasses for beer served in beer glasses, though no evidence that soft drink consumption differed 16. These authors argued that the ef...

AimsTo investigate the impact of unit and calorie information on drinking behaviour in an ad libitum taste test paradigm.MethodsIn this experimental human laboratory study, participants were randomized to one of four conditions, balanced by gender, using a 2 (unit information: present vs. absent) × 2 (calorie information: present vs. absent) between-subjects design. The percentage of beer consumed during the taste test was the primary outcome measure.ResultsAmong this largely undergraduate student population, we found no evidence that either unit or calorie information impacted alcohol consumption in an ad libitum taste test. A manipulation check indicated that few of the participants receiving either unit and/or calorie information could accurately recall the number of units and/or calories in the beverages provided to them, indicating low levels of engagement with this information. Analysis of qualitative reactions to calorie and unit labelling indicated possible negative unintended consequences of calorie and unit information, including using unit information to facilitate consumption of higher strength beverages, and calorie information to reduce food consumption prior to a drinking episode.ConclusionWe find no evidence to support an effect of unit or calorie information, a public-health initiative supported by the alcohol industry, on drinking behaviour. It is possible that compulsory unit and calorie labelling, at least in the numeric format used here, would have no effect on alcohol intake and may even have some negative unintended consequences among certain populations.

Increasing the availability of lower energy food options is a promising public health approach. However, it is unclear the extent to which availability interventions may result in consumers later ‘compensating’ for reductions in energy intake caused by selecting lower energy food options, and to what extent these effects may differ based on socioeconomic position (SEP). Our objective was to examine the impact of increasing availability of lower energy meal options on immediate meal energy intake and subsequent energy intake in participants of higher vs. lower SEP. In a within-subjects design N=77 UK adults ordered meals from a supermarket ready meal menu with standard (30%) and increased (70%) availability of lower energy options. The meals were delivered to be consumed at home, with meal intake measured using the Digital Photography of Foods Method. Post-meal compensation was measured using food diaries to determine self-reported energy intake after the meal and the next day. Participants consumed significantly less energy (196kcal, 95% CI: 138, 252) from the menu with increased availability of lower energy options versus the standard availability menu (p<.001). There was no statistically significant evidence that this reduction in energy intake was substantially compensated for (33% compensated, p=.57). The effects of increasing availability of lower energy food items were similar in participants from lower and higher SEP. Increasing the availability of lower energy food options is likely to be an effective and equitable approach to reducing energy intake which may contribute to improving diet and population health.

Summary Widespread availability of unhealthy food and drink products may contribute to socioeconomic patterning in obesity. Therefore, increasing the availability of healthier foods may be one approach to reducing obesity without widening existing inequalities. This systematic review and meta‐analysis examined the impact of increasing the availability of healthier food and drink on consumer behavior among individuals with higher and lower socioeconomic position (SEP). Eligible studies were required to use experimental designs to compare conditions of higher vs lower availability of healthier vs less healthy options on food choice‐related outcomes and measure SEP. Thirteen eligible studies were included. Odds of choosing a healthy item were higher when availability was increased for higher (OR = 5.0, 95% CI: 3.3, 7.7) and lower (OR = 4.9, CI: 3.0, 8.0) SEP. Increased availability of healthier foods was also associated with a decrease in energy content of selections for higher (−131 kcal; CI: −76, −187) and lower (−109 kcal; CI: −73, −147) SEP. There was no SEP moderation. Increasing the relative availability of healthier foods may be an equitable and effective approach to improve population‐level diet and address obesity, though more research is required testing this in real‐world environments.