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Brian Wansink
  • 159 Reach Run
    Ithaca, NY. 14850
Package size, plate shape, lighting, socializing, and variety are only a few of the environmental factors that can influence the volume of food consumed far more than most people realize. While education and increasing awareness might... more
Package size, plate shape, lighting, socializing, and variety are only a few of the environmental factors that can influence the volume of food consumed far more than most people realize. While education and increasing awareness might appear to be the solution to environmentally-stimulated overeating, a meta analysis of these studies show that it is unlikely to work. Using lessons from the National Mindless Eating Challenge, this chapter underscores how the Laboratory of Life – the real world – suggests key principles that academics, industry, and government can use when partnering to make tangible health-related changes in the lives of individuals.
Many eating studies in psychology, consumer behavior and marketing journals are dismissed, because they focus on how much one serves and not how much is eaten. We develop a means of estimating the percentage of self-served food that is... more
Many eating studies in psychology, consumer behavior and marketing journals are dismissed, because they focus on how much one serves and not how much is eaten. We develop a means of estimating the percentage of self-served food that is consumed under various conditions. An aggregate analysis was conducted of studies where participants served themselves food and where actual intake was measured. Analyses explored what percentage of food was consumed depending on population, food and situational cues and generally showed that adults consistently consume the vast majority (91.7%) of what they serve themselves. This was higher for meals (92.8%) than for snacks (76.1%) and higher when a person was not distracted (97.1%) than when he or she was distracted (88.8%). The percentage eaten did not vary between lab (90.7%) and field settings (91.9%). Because many eating behavior studies outside of nutrition measure food selection, but not intake, the aggregate estimates presented in this resear...
What percentage of the food you serve do you eat? If we could provide estimates of how much food people took they actually ate, this would open the door for a huge number of studies in in psychology, marketing, economics, and consumer... more
What percentage of the food you serve do you eat? If we could provide estimates of how much food people took they actually ate, this would open the door for a huge number of studies in in psychology, marketing, economics, and consumer behavior that have been dismissed or overlooked by nutrition and public health because they measured how much subjects served, but not how much they ate. Providing this "percent eaten" estimate was the objective of Wansink and Johnson. After aggregating results from a wide number of self-served meals and snacks, one conclusion was that most adults are members of the clean plate club. Regardless of their sex or ethnicity, it was estimated the average adult in these studies ate approximately 92% (unweighted by sample size) of what they served.In a thoughtful critique of this figure, Robinson et al raise excellent points that suggest this 92% figure is an upper bound, and perhaps even an overestimate of the actual percentage of self-served food a person consumes. One of their points is that many of these studies were lab-based studies where people knew they were being observed and may have acted differently in real life – perhaps serving more and eating less of it with the variation of plate size or perhaps by being less self conscious about serving a second or third helping.What also needs more examination and exploration is the somewhat contrary result that adults consumed a much greater percent of what they served than children. That is, while adults ate between 88.7% (when weighted by study sample sizes) and 92% (when averaged across studies), children (mostly elementary school aged) only ate an average of 59% of what they served themselves. Part of this could be explained these 326 children perhaps 1) not being aware of how hungry they are, 2) not being well-calibrated to know how much food would fill them up, 3) not knowing how much they will like a particularly new food, or 4) not ignoring their internal cues of satiety. This can also vary depending on whether the children are eating their food with utensils or with their hands, whether they are with friends, and whether they are extroverted or introverted.Robinson, et al’s excellent point about context is again relevant in our estimate that children eat only 59% of what they self-serve. Each of six studies used to arrive at this 59% figure were studies where children were not eating in the presence of their parents. Perhaps in the presence of their parents, this number is notably higher. Yet to a loving, but frustrated parent who wants their non-cooperating child to be a vegetable-eating member of the clean plate club, these lab results provide a powerful hidden value. They show that a child who only eats half to two-thirds of the food they serve themselves isn’t being wasteful, belligerent, or disrespectful. They are just being normal children. This should provide comfort and reduced anxiety for frustrated clean plate club parents.
Obesity has been linked to large portions of caloric, convenient, tempting, inexpensive food. These factors meet for lunch everyday at the growing number of all-you-can-eat restaurants and buffets. We investigated how a wide range of... more
Obesity has been linked to large portions of caloric, convenient, tempting, inexpensive food. These factors meet for lunch everyday at the growing number of all-you-can-eat restaurants and buffets. We investigated how a wide range of environmental variables and seemingly unrelated eating behaviors relate to how many times a person refills their plate while at the buffet. Trained observers recorded the height, weight, sex, age, and behavior of 387 patrons at Chinese all-you-can-eat restaurants. Various seating, serving, and eating behaviors were then compared across BMI levels. These included whether used larger plates vs. smaller plates (OR 1.16, P < 0.01), faced the buffet or away from it (OR 1.10, P < 0.001), whether they used chopsticks vs. forks (OR 0.90, P < 0.05), whether they browsed the buffet before eating vs. serving themselves immediately (OR 0.92, P < 0.001), and the number of average times they chewed their food. Interestingly, these Chinese buffet observations provide consistent ecological v...
A conceptual marketing-finance framework is proposed which links channel contracting in agriculture and the use of financial facilitating services (e.g., financial derivatives) to (shareholder) value creation. The framework complements... more
A conceptual marketing-finance framework is proposed which links channel contracting in agriculture and the use of financial facilitating services (e.g., financial derivatives) to (shareholder) value creation. The framework complements existing literature by explicitly including channel contract relationships as market-based assets that can be managed to reduce cash flow volatility and hence increase shareholder value. We show how financial facilitating services (e.g., derivatives) can be used to complement the cash flows components of channel contract relationships thereby further reducing the risk adjusted cost of capital and improving shareholder value. In a field study of producers, wholesalers, and processors, in the potato and meat industry the framework shows how shareholder value can be enhanced by using financial facilitating services, such as derivatives, to complement marketing channel relationships. Moreover, this study shows how producers and managers from agribusiness ...
Using psychological terms such as cognitive dissonance and confirmation bias, this study reveals how individual consumers inadequately process (food safety) information, pay limited attention to signals, and make purchase decisions that... more
Using psychological terms such as cognitive dissonance and confirmation bias, this study reveals how individual consumers inadequately process (food safety) information, pay limited attention to signals, and make purchase decisions that are bias towards their initial choices. While it is expected that reading extra information about potential risk associated with the food decreases consumers' willingness to pay (WTP), the magnitude of the impact varies across individuals. In general, consumer's judgment and information processing depend a lot on their initial beliefs or consumption status. They tend to use higher bidding prices to justify previous behaviors and selectively pay attention to information in favor of their initial choices. Using an incentive compatible auction mechanism, this study elicited consumers' WTP under different informational settings. Results showed that consumers bid much higher when they chose to commit to food items (treatment) than when they we...
Proceedings, 1999 Marketing Science Conference May 20-23, Syracuse, New York, USA
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Proceedings INFORMS 2000 Marketing Science Conference, June 22-25, Los Angeles, California, USA.
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This article aims to identify antecedents of food waste among lower-middle class families – a paradox, given the financial constraints this population faces. The importance of this research is evident in escalating environmental pressures... more
This article aims to identify antecedents of food waste among lower-middle class families – a paradox, given the financial constraints this population faces. The importance of this research is evident in escalating environmental pressures for better use of our planet’s scarce resources. Given that most of the world is low-income, any behavioral change in this population is likely to have a considerable impact. Empirical data were collected from 14 lower-middle income Brazilian households, based on observations, in-depth interviews, photographs and a focus group (n=6). Five major categories of food waste antecedents were identified: (1) excessive purchasing, (2) over-preparation, (3) caring for a pet, (4) avoidance of leftovers and (5) inappropriate food conservation. Several subcategories were also found, including impulse buying, lack of planning and preference for large packages. Surprisingly, findings show that strategies used to save money – such as buying groceries in bulk, monthly shopping trips, preference for supermarkets and cooking from scratch – actually end up generating more food waste. This mitigates the savings made during the purchasing phase.
Rational choice theory commonly assumes that the presence of unselected choices cannot impact which among the remaining choices is selected—-often referred to as “independence of irrelevant alternatives.†We show that such seemingly... more
Rational choice theory commonly assumes that the presence of unselected choices cannot impact which among the remaining choices is selected—-often referred to as “independence of irrelevant alternatives.†We show that such seemingly irrelevant alternatives influence choice in a school lunch setting. In these lunchrooms, we provide evidence that the presence of specific side dishes-—trigger foods-—can strongly increase the sales of
Although incidental affect has been shown to influence both attitude and purchase behavior, it has not been extended to actual consumption. This research investigates whether specific affective states influence food consumption and... more
Although incidental affect has been shown to influence both attitude and purchase behavior, it has not been extended to actual consumption. This research investigates whether specific affective states influence food consumption and whether this influence is moderated by factors such as information and the nature of the product (hedonic versus less hedonic). The authors show that an integrative mood management and mood evaluation framework accounts for this relationship more effectively than a self-regulation explanation. A preliminary test and two lab studies show that people eat larger amounts of hedonic foods (buttered popcorn and M&M's) when they are in a sad state than when they are in a happy state and that this effect is attenuated when nutritional information is present. In contrast, they tend to eat larger amounts of a less hedonic product (raisins) when they are in a happy state than when they are in a sad state. The authors discuss implications for responsible marketer...
Proceedings 7th Biennial Behavioral Decision Research in Management Conference, May 19-21, Tucson, Arizona, USA.
"2002 Marketing Science Conference, June 27-30, Edmonton, Canada. "
In order to integrate unfamiliar food products into a given culture the process must take into account the culture it is being introduced into. It is unwise to take a product, blindly introduce it into a culture, and expect it to do well.... more
In order to integrate unfamiliar food products into a given culture the process must take into account the culture it is being introduced into. It is unwise to take a product, blindly introduce it into a culture, and expect it to do well. There are too many unknown cultural factors at work that would complicate the integration. Instead, product integration needs to take into account the specific cultural consumption behavior that is influenced by cultural context and perception of food. To better understand these cultural influences, analysis was done on how an unfamiliar product of soy can be potentially integrated into two different markets, Russia and Colombia. This research develops an exploratory framework for increasing consumption of a commodity taking into consideration cultural context and utilitarian/hedonic food perceptions that can be used as a template for unfamiliar food introductions around the world. The authors then apply the consumer acceptance-oriented framework for increasing soy consumption in the cases of Russia and Colombia. Finally, insights related to distribution, message positioning, and marketing strategy that can be generated by the framework and will be helpful in determining what policy will work best for the integration of soy in the markets are discussed.
The objective of this article is to analyze whether visual plate-related dietary guidance systems-such as the MyPlate guideline or the Half-Plate Rule-help people eat better when dining at home or in restaurants. Methods To help explore... more
The objective of this article is to analyze whether visual plate-related dietary guidance systems-such as the MyPlate guideline or the Half-Plate Rule-help people eat better when dining at home or in restaurants. Methods To help explore this, 104 young adults were randomly assigned to follow either (1) USDA MyPlate guidelines, (2) the Half-Plate Rule, or (3) no guidelines (control condition). They then used their assigned guidelines to complete the survey while eating a dinner of their choice. They completed a food diary for the meal and then completed a survey about their experience. Results Both the two visual dietary guidance systems (My Plate and the Half-Plate Rule) were considered easy to understand and easy to follow, and they left people with fewer questions about what to eat (all p < 0.01). Understandability is important because those people who rated a system "easy to follow" indicated they had consumed less meat than usual (r = 0.268), but understandability was uncorrelated with fruit and vegetable intake (r = 0.092) and carbohydrate intake (r = 0.069). Conclusions There are three key conclusions to these and other findings: first, the simplest guidance system may be more effective than none. Second, even the most perfect dietary guidance system will not change behavior if (a) the foods are not available, or (b) it is not followed. Third, guidance systems could over-increase the consumption of some foods (such as dairy) they specifically mention, presumably because it makes them more salient in one's mind.
The objective of USDA’s behavioral economics-child nutrition research initiative is to improve the food choices American children make at school as participants in USDA’s National School Lunch and ...
A previous sales data analysis demonstrated success in selling healthier items at a concession stand. Questions remained regarding student satisfaction and whether the intervention reached non-health-conscious students. Cross-sectional... more
A previous sales data analysis demonstrated success in selling healthier items at a concession stand. Questions remained regarding student satisfaction and whether the intervention reached non-health-conscious students. Cross-sectional anonymous samples of students at a large midwestern high school were surveyed before and after an intervention improved the number of healthier items available at the concession stand. The survey was completed by 301 students preintervention and 314 students postintervention. Satisfaction remained good (3.7 preintervention and 3.6 postintervention). Satisfaction with the variety and taste of foods increased. We compared students who felt having healthy items were important at the concessions to those who did not. Overall satisfaction with concessions did not differ between groups. The latter group (healthy items not important) reported improved satisfaction with food variety (2.8 to 3.1, p = .02) and the former reported improved satisfaction with heal...
To evaluate the efficacy of a small change behavioral weight loss intervention with or without a positive affect/self-affirmation (PA/SA) component on weight loss at 12 months. Black and Hispanic adults (N = 405) with body mass index... more
To evaluate the efficacy of a small change behavioral weight loss intervention with or without a positive affect/self-affirmation (PA/SA) component on weight loss at 12 months. Black and Hispanic adults (N = 405) with body mass index 25-50 kg/m(2) selected one of ten small change eating strategies and a physical activity goal, randomly with/without PA/SA. Participants were followed by community health workers at set intervals (weekly in months 1-3; biweekly in months 4-9; once monthly in months 10-12). There was no difference in weight loss at 12 months between participants in the small change approach alone (1.1%) versus the small change PA/SA intervention (1.2%). During treatment, 9% of participants lost at least 7% of their initial body weight. Participants who reported more interval life events had a lower likelihood of losing weight (P &lt; 0.0001). However, those randomized to the small change PA/SA intervention gained less weight (+0.3% vs. 2.3% gain; P &lt; 0.0001). The smal...
Food pantries and food banks are interested in cost-effective methods to encourage the selection of targeted foods without restricting choices. Thus, this study evaluates the effectiveness of nudges toward targeted foods. In... more
Food pantries and food banks are interested in cost-effective methods to encourage the selection of targeted foods without restricting choices. Thus, this study evaluates the effectiveness of nudges toward targeted foods. In October/November 2014, we manipulated the display of a targeted product in a New York State food pantry. We evaluated the binary choice of the targeted good when we placed it in the front or the back of the category line (placement order) and when we presented the product in its original box or unboxed (packaging). The average uptake proportion for the back treatment was 0.231, 95% CI = 0.179, 0.29, n = 205, and for the front treatment, the proportion was 0.337, 95% CI = 0.272, 0.406, n = 238 with an odds ratio of 1.688, 95% CI = 1.088, 2.523. The average uptake for the unboxed treatment was 0.224, 95% CI = 0.174, 0.280, n = 255, and for the boxed intervention, the proportion was 0.356, 95% CI = 0.288, 0.429, n = 188 with an odds ratio of 1.923, 95% CI = 1.237, ...
Distractions, stress, or being overburdened with options can lead to the selection of more hedonic foods. Similarly, package size, plate shape, lighting, socializing, and variety are only a few of the environmental factors that can... more
Distractions, stress, or being overburdened with options can lead to the selection of more hedonic foods. Similarly, 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 suggests where consumer rationality related to food choice breaks down, what myths we need to see through, and what possible solutions lie ahead.
ABSTRACT
ABSTRACT

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Where have all the saxophones gone in pop music? Quantifying their popularity over time could give useful insights into the trends and psychology behind hit songs. An analysis was conducted of 1081 Top 40 songs (1955-2020) with sax solos.... more
Where have all the saxophones gone in pop music? Quantifying their popularity over time could give useful insights into the trends and psychology behind hit songs. An analysis was conducted of 1081 Top 40 songs (1955-2020) with sax solos. A rollercoaster of popularity was found with two dramatic peaks in the early 1960s and again 20 years later in the early 1980s. By 1990, the number of sax solos has dropped to almost zero where it remains today. The tenor saxophone comprised 63.2% of the solos in this time period (alto 34.1%; baritone 8.7%; soprano 4.4%). Interestingly, while the popularity of the baritone decreased with time (p < .01), the popularity of the soprano increased (p = .021) probably because its ability to cut through busy songs. This general trend corresponds with changes in technology (the prevalence of synthesizers), economics (the cost of saxophone players), and taste-the latter of which appears to be more influenced both by individual creative artists and by bold players than previously thought. There are promising implications for educators and musicians of all instruments.
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What can a parent, peer, or professional say to a bullied and body shamed child? This research elicited and categorized the words that were reported as being most memorably hurtful and helpful to 341 young people (79.5% female; average... more
What can a parent, peer, or professional say to a bullied and body shamed child? This research elicited and categorized the words that were reported as being most memorably hurtful and helpful to 341 young people (79.5% female; average age 25.03 years) who had been body shamed. The most memorably hurtful comments generally involved
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Can visual plate-related dietary guidance systems-such as the MyPlate guideline or the Half-Plate Rule-help people eat better when dining at home or in restaurants? To help explore this, 104 young adults completed a food diary study after... more
Can visual plate-related dietary guidance systems-such as the MyPlate guideline or the Half-Plate Rule-help people eat better when dining at home or in restaurants? To help explore this, 104 young adults completed a food diary study after having been randomly assigned to follow either 1) USDA MyPlate guidelines, 2) the Half-Plate Rule, or 3) no guidelines (control condition). Both of the visual dietary guidance systems were considered easy to understand, to follow, and left people with fewer questions about what to eat (all p<.01). Moreover, people who rated a system "easy to follow" indicated they had consumed less (meat (r = .268), but this was uncorrelated with fruit and vegetable intake (r =.092) and carbohydrate intake (r = .069). There are three key conclusions to these and other findings: First, the simplest guidance system may be more effective than no system. Second, even the most perfect dietary guidance system will not change behavior if the foods are not available or it is not followed. Third, guidance systems could over-increase the consumption of any food they specifically mention.
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In 2018, six of my research articles in JAMA-related journals were retracted. These retractions offer some useful lessons to scholars, and they also offer some useful next steps to those who want to publish eating behavior research in... more
In 2018, six of my research articles in JAMA-related journals
were retracted. These retractions offer some useful lessons to
scholars, and they also offer some useful next steps to those who
want to publish eating behavior research in medical journals or in the
social sciences.

These six different papers offer some topic-related roadmaps
that could be useful. First, they were originally of interest to journals
in the Journal of the American Medical Association (JAMA) network,
and they would probably be of interest to other journals in medicine,
behavioral economics, marketing, nutrition, psychology, health, and
consumer behavior. Second, they each show what a finished paper
might look like. They show the positioning, relevant background
research, methodological approach, and relevance to clinical practice
or to everyday life.

I think all of these topics are interesting and have every-day
importance. This document provides a two-page template for each
one that shows 1) An overview why it was done, 2) the abstract (or
a summary if there was no abstract), 3) the reason it was retracted,
4) how it could be done differently, and 5) promising new research
opportunities on the topic.
Research Interests:
In 2017-19, about 18 of my research articles were retracted. These retractions offer some useful lessons to scholars, and they also offer some useful next steps to those who want to publish in the social sciences. Two of these steps... more
In 2017-19, about 18 of my research articles were retracted. These
retractions offer some useful lessons to scholars, and they also offer some
useful next steps to those who want to publish in the social sciences. Two of
these steps include 1) Choose a publishable topic, and 2) have a rough mental
roadmap of what the finished paper might look. That is, what’s the positioning,
the study, and the possible contribution.

The topics I’ve described here offer one set of roadmaps that could
be useful. First, they were of interest to journals in medicine, behavioral
economics, marketing, nutrition, psychology, health, and consumer behavior.
Second, they each show what a finished paper might look like. They show
the positioning, relevant background research, methodological tips, and key
implications.

I find all of these topics super interesting and of practical importance.
This document provides a two-page template for each one that shows 1) An
overview why it was done, 2) the abstract (or a summary if there was no
abstract), 3) the reason it was retracted, 4) how it could be done differently,
and 5) promising new research opportunities on the topic.
Watching people can be better than listening to them. Observational research can illuminate the unconscious behaviors that lead to breakthrough solutions to problems. This chapter is a manual on to use observational research to solve... more
Watching people can be better than listening to them. Observational research can illuminate the unconscious behaviors that lead to breakthrough solutions to problems. This chapter is a manual on to use observational research to solve problems. Specifically, it focuses on how to find potential breakthrough insights, how to confirm them (using quantitative coding), and how to use the results to develop solutions to problems.