PubMed Health⌕ Search

Biomedical subjects

Brian Wansink

Publications and source records attributed to Brian Wansink.

At least 19 recordsLinked to original sources
PubMed2006

Meal size, not body size, explains errors in estimating the calorie content of meals.

BACKGROUND: Although most people underestimate the calories they consume during a meal or during the day, calorie underestimation is especially extreme among overweight persons. The reason for this systematic bias is unknown. OBJECTIVE: To investigate whether the association between calorie underestimation and body mass reflects a tendency for all persons to underestimate calories as the size of a meal increases. DESIGN: Overweight and normal-weight adults estimated the number of calories of a fast-food meal they had ordered and eaten (study 1) or of 15 fast-food meals that were chosen by the experimenter (study 2) in a randomized, controlled trial. Their estimations were compared with the actual number of calories of the meals. SETTING: Study 1 was a field study conducted in fast-food restaurants in 3 medium-sized midwestern U.S. cities. Study 2 was conducted in a laboratory at a major U.S. research university. PARTICIPANTS: Study 1 involved 105 lunchtime diners (average body mass index [BMI], 24.2 kg/m2 [range, 17.2 to 33.5 kg/m2]). Study 2 involved 40 undergraduate students (average BMI, 23.2 kg/m2 [range, 16.1 to 32.3 kg/m2]). MEASUREMENTS: Participants were asked to estimate the number of calories in a fast-food meal they had ordered and eaten (study 1) or in 15 sizes of the same fast-food meal (study 2). The actual number of calories in the meals in the field study was obtained by unobtrusively recording the food that was ordered (identified from the wrappings and containers). Weight and height were self-reported. RESULTS: Although participants strongly underestimated the number of calories in larger meals (by -38.0% in study 1 and by -22.6% in study 2), they almost perfectly estimated the number of calories in smaller meals (by -2.9% in study 1 and by 3.0% in study 2). After the authors controlled for body weight-related differences in meal size, the calorie estimations of normal-weight and overweight participants were identical in both studies. LIMITATIONS: These studies examined fast-food meals. Weight and height were self-reported. There were too few observations to distinguish between obese (BMI > or =30 kg/m2) and overweight (BMI >25 kg/m2 but <30 kg/m2) participants. CONCLUSIONS: Greater underestimation of calories by overweight persons is a consequence of their tendency to consume larger meals. Calorie underestimation is related to meal size, not body size.

Adult↗
PubMed2006

The sweet tooth hypothesis: how fruit consumption relates to snack consumption.

Building on prior work related to taste preferences of fruit lovers, we investigate the "sweet tooth" hypothesis. First, using CSFII survey data, we show that fruit consumption is more highly related to sweet snack consumption than it is to salty snack consumption. Second, a follow-up study with a different population supports the relationship by showing that sweet snack consumption is more related to fruit consumption than it is to vegetable consumption. Knowing that people who frequently eat sweet snacks may be predisposed to increasing their fruit consumption will enable better targeting and tailoring of educational efforts, such as those used in the 5-a-Day for Better Health campaign.

Adult↗
PubMed2006

Ice cream illusions bowls, spoons, and self-served portion sizes.

BACKGROUND: Because people eat most of what they serve themselves, any contextual cues that lead them to over-serve should lead them to over-eat. In building on the size-contrast illusion, this research examines whether the size of a bowl or serving spoon unknowingly biases how much a person serves and eats. METHODS: The 2 x 2 between-subjects design involved 85 nutrition experts who were attending an ice cream social to celebrate the success of a colleague in 2002. They were randomly given either a smaller (17 oz) or a larger (34 oz) bowl and either a smaller (2 oz) or larger (3 oz) ice cream scoop. After serving themselves, they completed a brief survey as their ice cream was weighed. The analysis was conducted in 2003. RESULTS: Even when nutrition experts were given a larger bowl, they served themselves 31.0% more (6.25 vs 4.77 oz, F(1, 80) = 8.05, p < 0.01) without being aware of it. Their servings increased by 14.5% when they were given a larger serving spoon (5.77 vs 5.04 oz, F(1, 80)=2.70, p = 0.10). CONCLUSIONS: People could try using the size of their bowls and possibly serving spoons to help them better control how much they consume. Those interested in losing weight should use smaller bowls and spoons, while those needing to gain weight--such as the undernourished or aged--could be encouraged to use larger ones. Epidemiologic implications are discussed.

Eating↗
PubMed2006

Position of the American Dietetic Association: food and nutrition misinformation.

It is the position of the American Dietetic Association (ADA) that food and nutrition misinformation can have harmful effects on the health, well-being, and economic status of consumers. Nationally credentialed dietetics professionals working in health care, academia, public health, the media, government, and the food industry are uniquely qualified to advocate for and promote science-based nutrition information to the public, function as primary nutrition educators to health professionals, and actively correct food and nutrition misinformation. Enormous scientific advances have been made in the area of food and nutrition, leading to a fine-tuning of recommendations about healthful eating. Consumers have become increasingly aware of the nutrition-health link and reliant on nutrition information to base their decisions, and have assumed partial responsibility for changing their eating behaviors. Unfortunately, these same trends also create opportunities for food and nutrition misinformation to flourish. News reports rarely provide enough context for consumers to interpret or apply the advice given, and preliminary findings often attract unmerited and misleading attention. Effective nutrition communication must be consumer-friendly and contain sufficient context to allow consumers to consider the information and determine whether it applies to their unique health and nutritional needs. Consistent with ADA's organizational vision that members "are the leading source of nutrition expertise," ADA recognizes its responsibility to help consumers identify food and nutrition misinformation in the following ways: (a) ADA members should provide consumers with sound, science-based nutrition information and help them to recognize misinformation; (b) ADA members need to be the primary source of sound, science-based nutrition information for the media and to inform them when misinformation is presented; and (c) ADA members should continue to diligently work with other health care practitioners, educators, policy makers, and food and dietary supplement industry representatives to responsibly address the health and psychological, physiological, and economic effects of nutrition-related misinformation.

Communication↗
PubMed2005

Shape of glass and amount of alcohol poured: comparative study of effect of practice and concentration.

OBJECTIVE: To determine whether people pour different amounts into short, wide glasses than into tall, slender ones. DESIGN: College students practised pouring alcohol into a standard glass before pouring into larger glasses; bartenders poured alcohol for four mixed drinks either with no instructions or after being told to take their time. SETTING: University town and large city, United States. PARTICIPANTS: 198 college students and 86 bartenders. MAIN OUTCOME MEASURES: Volume of alcohol poured into short, wide and tall, slender glasses. RESULTS: Aiming to pour a "shot" of alcohol (1.5 ounces, 44.3 ml), both students and bartenders poured more into short, wide glasses than into tall slender glasses (46.1 ml v 44.7 ml and 54.6 ml v 46.4 ml, respectively). Practice reduced the tendency to overpour, but not for short, wide glasses. Despite an average of six years of experience, bartenders poured 20.5% more into short, wide glasses than tall, slender ones; paying careful attention reduced but did not eliminate the effect. CONCLUSIONS: To avoid overpouring, use tall, narrow glasses or ones on which the alcohol level is premarked. To avoid underestimating the amount of alcohol consumed, studies using self reports of standard drinks should ask about the shape of the glass.

Adult↗
PubMed2005

Hierarchy of nutritional knowledge that relates to the consumption of a functional food.

OBJECTIVE: We assessed how consumption of a functional food relates to different combinations of nutritional knowledge. METHODS: American and Canadian subjects were asked by mail survey about their level of knowledge about soy and were assigned to one of four groups based on whether they had 1) no knowledge of soy, 2) attribute-related knowledge of soy, 3) consequence-related knowledge of consuming soy, or 4) both types of knowledge. Content analysis and analysis of variance were performed. RESULTS: The level of nutritional knowledge about soy did not necessarily influence how much people liked soy but was related to how much people consumed soy. In particular, consumers who were able to link attribute-related knowledge about soy to consequence-related knowledge about consuming soy were much more likely to consume soy than were those who only had one type of knowledge (average P < 0.007). CONCLUSIONS: Nutritional knowledge most likely correlates with consumption when people have attribute-related knowledge of the food and consequence-related knowledge of how it will benefit them. It is not the amount but the type of knowledge that matters. Educational strategies based only on attribute-related knowledge of functional foods and healthy products ("passing the nutrition quiz") may not effectively encourage the actual consumption of the food. Health care professionals and dietitians must link food attributes with personal health consequences when communicating to their patients.

Adult↗
PubMed2005

Bottomless bowls: why visual cues of portion size may influence intake.

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.

Adolescent↗
PubMed2005

Fluid consumption and the potential role of canteen shape in minimizing dehydration.

Hypohydration can unknowingly occur in military personnel during exertion, especially in the heat. Such dehydration can impair cognitive and physical performance. Some portion of exercise-induced dehydration may be offset by changing the perceptual biases of soldiers when filling and drinking from canteens. Using comparably sized water bottles, we investigated this perceptual bias with 50 Army and Marine ROTC students by showing that those given short, wide, clear water bottles poured and drank more water than those given taller bottles that held the same volume. Even although those given short, wide water bottles poured 38% more water, they did not perceive themselves as having poured or drunk more. The implications for decreasing dehydration in the field and in garrison are discussed.

Dehydration↗
PubMed2004

Environmental factors that increase the food intake and consumption volume of unknowing consumers.

Package size, plate shape, lighting, socializing, and variety are only a few of the environmental factors that can influence the consumption volume of food far more than most people realize. Although such environmental factors appear unrelated, they generally influence consumption volume by inhibiting consumption monitoring and by suggesting alternative consumption norms. For researchers, this review suggests that redirecting the focus of investigations to the psychological mechanisms behind consumption will raise the profile and impact of research. For health professionals, this review underscores how small structural changes in personal environments can reduce the unknowing overconsumption of food.

Consumer Behavior↗
PubMed2003

Exploring comfort food preferences across age and gender.

Building on findings related to physiological and psychological motivations of food preference, this research develops a framework to examine preferences toward comfort foods. Study 1 used a North American survey of 411 people to determine favored comfort foods, and Study 2 quantified the preferences for these foods across gender and across age groups using a stratified sample of 1005 additional people. Consistent with hypotheses, the findings showed different comfort food preferences across gender and across age. Males preferred warm, hearty, meal-related comfort foods (such as steak, casseroles, and soup), while females instead preferred comfort foods that were more snack related (such as chocolate and ice cream). In addition, younger people preferred more snack-related comfort foods compared to those over 55 years of age. Associations with guilty feelings underscored how these different preferences between males and females may extend to areas of application.

Affect↗
PubMed2003

Profiling taste-motivated segments.

Early adopters of unfamiliar, but nutritious foods can do so because of a combination of taste-motivations and health-motivations. Yet because taste can provide an enduring motivation for dietary change, profiling the taste-motivated segment of a particular food might prove useful in identifying and stimulating adoption among similar predisposed segments. This manuscript describes a basic qualitative and quantitative procedure--in the context of soy consumption--that can be used to begin profiling taste-motivated segments of a particular food. A survey of 606 North Americans indicates that when contrasted to health-motivated consumers of soy, taste-motivated consumers were more likely to claim they are opinion-leaders who live with (or who are) great cooks, and they were more likely to exhibit other behaviors associated with food appreciation, such as dining out and wine consumption. In light of these findings, instead of encouraging people to eat soy solely for health reasons, a more productive method may be to target those who are more likely to prefer it for taste-motivated reasons. This same method has potential for more effectively promoting the consumption of fruits and vegetables or the consumption of genetically enhanced foods among predisposed taste-motivated segments.

Attitude to Health↗
PubMed2003

Interactions between forms of fat consumption and restaurant bread consumption.

How does fat consumption influence the consumption of companion foods such as bread? Adult restaurant goers who were randomly given olive oil for their bread used 26% more oil on each piece of bread compared to those who were given block butter, but they ended up eating 23% less bread in total. This finding illustrates one way in which fat intake can interact with the consumption of companion foods.

Adult↗
PubMed2001

Relation of Soy Consumption to Nutritional Knowledge.

Is it reasonable to believe that the consumption of medicinal and functional foods such as soy is driven by nutritional knowledge? A national survey of 770 U.S. consumers indicated that 39% of male and female subjects did not know of any health benefits associated with soy. Among those who know of soy's nutritional benefits, consumption occurred only among those who perceived these benefits as specifically relevant to themselves. People who had even a slight familiarity with functional foods were more likely to consume soy. Improving the taste properties of soy appeared to have a more dramatic potential impact on the consumption of those who were knowledgeable about functional and medicinal foods than on the general population.

Journal Article↗