***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: OBJECTIVE Using self-refilling soup bowls , this study examined whether visual cues related to portion size can influence intake volume without altering either estimated intake or satiation . RESEARCH METHODS AND PROCEDURES Fifty-four participants ( BMI , 17.3 to 36.0 kg/m2 ; 18 to 46 years of age ) were recruited to participate in a study involving soup . The experiment was a between-subject design with two visibility levels : 1 ) an accurate visual cue of a food portion ( normal bowl ) vs. 2 ) a biased visual cue ( self-refilling bowl ) . The soup apparatus was housed in a modified restaurant-style table in which two of four bowls slowly and imperceptibly refilled as their contents were consumed . Outcomes included intake volume , intake estimation , consumption monitoring , and satiety . RESULTS Participants who were unknowingly eating from self-refilling bowls  ate more soup [ 14.7+/-8.4 vs. 8.5+/-6.1 oz ; F(1,52)=8.99 ; p<0.01 ] than those eating from normal soup bowls . However , despite consuming 73 % more , they did not believe they had consumed more , nor did they perceive themselves as more sated than those eating from normal bowls . This was unaffected by BMI . DISCUSSION These findings are consistent with the notion that the amount of food on a plate or bowl increases intake because it influences consumption norms and expectations and it lessens one 's reliance on self-monitoring . It seems that people use their eyes to count calories and not their stomachs . The importance of having salient , accurate visual cues can play an important role in the prevention of unintentional overeating OBJECTIVE It is often believed that people overeat the foods they like . We investigated whether environmental cues such as packaging and container size are so powerful that they can increase our intake of foods that are less palatable . DESIGN , SETTING , AND PARTICIPANTS In a 2 x 2 between-subjects design , 158 moviegoers in Philadelphia ( 57.6 % male ; 28.7 years ) were r and omly given a medium ( 120 g ) or a large ( 240 g ) container of free popcorn that was either fresh or stale ( 14 days old ) . Following the movie , consumption measures were taken , along with measures of perceived taste . OUTCOME MEASURES AND RESULTS Moviegoers who were given fresh popcorn ate 45.3 % more popcorn when it was given to them in large containers . This container-size influence is so powerful that even when the popcorn was disliked , people still ate 33.6 % more popcorn when eating from a large container than from a medium-size container . CONCLUSIONS AND IMPLICATION S Even when foods are not palatable , large packages and containers can lead to overeating . The silver lining of these findings may be that portion size can also be used to increase the consumption of less preferred healthful foods , such as raw vegetables Young and Nestle suggested that the increase in the portion size of food products evident in the United States during the past 20 years may be responsible for the epidemic of overweight and obesity . They based their conclusion on statistical correlations . The purpose of the present study was to provide experimental evidence to support their proposal . Cornell undergraduate students were given access to a buffet lunch on Monday , Wednesday , and Friday and were told this was a test of flavor enhancers . They were instructed to eat as much or as little as they wanted . On the same days of the following week , the subjects were divided into 3 groups . Each group was served either 100 % , 125 % , or 150 % of the amount of food they had consumed the previous week . When larger amounts were served , significantly greater amounts of food were consumed . Each of the 4 foods that comprised the meal ( soup , pasta , breadsticks , ice cream ) increased significantly in proportion to the portion size . The data clearly support the hypothesis proposed by Young and Nestle and support the powerful role that environment plays in determining energy intake and potential increases in body weight Background While environmental and situational cues influence food intake , it is not always clear how they do so . We examine whether participants consume more when an eating occasion is associated with meal cues than with snack cues . We expect their perception of the type of eating occasion to mediate the amount of food they eat . In addition , we expect the effect of those cues on food intake to be strongest among those who are hungry . Methods One-hundred and twenty-two undergraduates ( 75 men , 47 women ; mean BMI = 22.8 , SD = 3.38 ) were r and omly assigned to two experimental conditions in which they were offered foods such as quesadillas and chicken wings in an environment that was associated with either meal cues ( ceramic plates , glasses , silverware , and cloth napkins at a table ) , or snack cues ( paper plates and napkins , plastic cups , and no utensils ) . After participants finished eating , they were asked to complete a question naire that assessed their hunger , satiety , perception of the foods , and included demographic and anthropometric questions . In addition , participants ' total food intake was recorded . Results Participants who were in the presence of meal-related cues ate 27.9 % more calories than those surrounded with snack cues ( 416 versus 532 calories ) . The amount participants ate was partially mediated by whether they perceived the eating occasion to be a meal or a snack . In addition , the effect of the environmental cues on intake was most pronounced among participants who were hungry . Conclusions The present study demonstrated that environmental and situational cues associated with an eating occasion could influence overall food intake . People were more likely to eat foods when they were associated with meal cues . Importantly , the present study reveals that the effect of these cues is uniquely intertwined with cognition and motivation . First , people were more likely to eat ambiguous foods when they perceived them as a meal rather than a snack . Second , the effect of the environmental cues on intake was only observed among those who were hungry The objective of this study was to test if proximity of a food or preference for a food influences food intake in a competitive food environment in which one low calorie/low fat ( apple slices ) and one higher calorie/higher fat ( buttered popcorn ) food was available in the same environment . The proximity of popcorn and apple slices was manipulated and 56 participants were r and omly assigned to groups . In Group Apples Near , apple slices were placed near ( within arms reach ) a participant and popcorn was placed far ( 2 m away ) . In Group Popcorn Near , buttered popcorn was placed near and apple slices were placed far . As a control for the absence of a proximity manipulation , Group Both Near had both test foods placed near . Although participants rated the popcorn as more liked than apples , the food that was placed closer to the participant was consumed most in the two experimental groups , regardless of preference ( R(2)=0.38 ) . Total energy intake was reduced most when popcorn was placed far from a participant compared to when it was placed near ( R(2)=0.24 ) . The effects reported here were not moderated by BMI and did not vary by sex . In all , the results support the hypothesis that making a low calorie food more proximate will reduce total energy intake and increase intake of a low calorie food , even when a higher calorie and more preferred food is also available , but less proximate In a cross-over study , participants ( n=59 ) were r and omly assigned to receive either 100 kcal packs or st and ard size packages of snacks for 1 week . After a minimum of a 1-week washout period , participants received the other form of the snack for 1 week . Snack consumption was recorded by participants in a diary . Participants consumed an average of 186.9 fewer grams of snacks per week when receiving 100 kcal snack packs compared to st and ard size packages of snacks . Post hoc comparisons revealed the effect of package size depended on both r and omization order and study week . Total grams of snacks consumed in week 1 differed significantly between the two r and omized groups . In week 2 , however , grams of snacks did not differ significantly between the two groups . This interaction was primarily due to a significantly lower consumption of snacks from st and ard size packages in the week following the portion-controlled packages . The results suggest that portion-controlled packaging reduce total intake from the provided snacks . Further , initial exposure to portion-controlled packages might have increased awareness of portion size such that less was consumed when larger packages were available Objective To assess the impact of  fast food restaurants  adding calorie labelling to menu items on the energy content of individual purchases . Design Cross sectional surveys in spring 2007 and spring 2009 ( one year before and nine months after full implementation of regulation requiring chain restaurants ’ menus to contain details of the energy content of all menu items ) . Setting 168 r and omly selected locations of the top 11 fast food chains in New York City during lunchtime hours . Participants 7309 adult customers interviewed in 2007 and 8489 in 2009 . Main outcome measures Energy content of individual purchases , based on customers ’ register receipts and on calorie information provided for all items in menus . Results For the full sample , mean calories purchased did not change from before to after regulation ( 828 v 846 kcal , P=0.22 ) , though a modest decrease was shown in a regression model adjusted for restaurant chain , poverty level for the store location , sex of customers , type of purchase , and inflation adjusted cost ( 847 v 827 kcal , P=0.01 ) . Three major chains , which accounted for 42 % of customers surveyed , showed significant reductions in mean energy per purchase ( McDonald ’s 829 v 785 kcal , P=0.02 ; Au Bon Pain 555 v 475 kcal , P<0.001 ; KFC 927 v 868 kcal , P<0.01 ) , while mean energy content increased for one chain ( Subway 749 v 882 kcal , P<0.001 ) . In the 2009 survey , 15 % ( 1288/8489 ) of customers reported using the calorie information , and these customers purchased 106 fewer kilocalories than customers who did not see or use the calorie information ( 757 v 863 kcal , P<0.001 ) . Conclusion Although no overall decline in calories purchased was observed for the full sample , several major chains saw significant reductions . After regulation , one in six lunchtime customers used the calorie information provided , and these customers made lower calorie choices Objectives : The supermarket industry now services many customers through online food shopping over the Internet . The Internet shopping process offers a novel opportunity for the modification of dietary patterns . The aim of this study was to evaluate the effects on consumers ' purchases of saturated fat of a fully automated computerised system that provided real-time advice tailored to the consumers ' specific purchases recommending foods lower in saturated fat . Design : This study was a blinded , r and omised controlled trial . Setting : The study was conducted in Sydney , New South Wales , Australia . Participants : The participants were consumers using a commercial online Internet shopping site between February and June 2004 . Interventions : Individuals assigned to intervention received fully automated advice that recommended specific switches from selected products higher in saturated fat to alternate similar products lower in saturated fat . Participants assigned to control received general non-specific advice about how to eat a diet lower in saturated fat . Outcome Measures : The outcome measure was the difference in saturated fat ( grams per 100 g of food ) in shopping baskets between the intervention and control groups . Results : There were 497 r and omised participants , mean age 40 y , each shopping for an average of about three people . The amount of saturated fat in the foods purchased by the intervention group was 0.66 % lower ( 95 % confidence interval 0.48–0.84 , p < 0.001 ) than in the control group . The effects of the intervention were sustained over consecutive shopping episodes , and there was no difference in the average cost of the food bought by each group . Conclusions : Fully automated , purchase-specific dietary advice offered to customers during Internet shopping can bring about changes in food purchasing habits that are likely to have significant public health implication s. Because implementation is simple to initiate and maintain , this strategy would likely be highly cost-effective Large food portions may be facilitating excess energy intake ( EI ) and adiposity among adults . The present study aim ed to assess the extent to which EI and amounts of foods consumed are influenced by the availability of different-sized food portions . A r and omised within-subject cross-over , fully residential design was used , where forty-three ( twenty-one men and twenty-two women ) normal-weight and overweight adults were r and omly allocated to two separate 4 d periods where they were presented with either ' st and ard ' or ' large ' food portions of the same foods and beverages . The main outcome measures were the amount of food ( g ) and EI ( MJ ) consumed throughout each study period . Mean EI over 4 d was significantly higher on the large portion condition compared with the st and ard condition in the total group ( 59.1 ( sd 6.6 ) v. 52.2 ( sd 14.3 ) MJ ; P = 0.020 ) ; men and women increased their EI by 17 % ( 10 ( sd 6.5 ) MJ ; P < 0.001 ) and 10 % ( 4 ( sd 6.5 ) MJ ; P = 0.005 ) respectively when served the large food portions relative to the st and ard food portions . The increased intakes were sustained over the 4 d in the large portion condition with little evidence of down-regulation of EI and food intake being made by subjects . Increased food portion size result ed in significant and sustained increases in EI in men 
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Conclusions This analysis demonstrates Nudge holds promise as a public health strategy to combat obesity .