In 2017, a large corpus of Wansink’s research faced scrutiny which led to several retractions and corrections and prompted an investigation by Cornell into the integrity of his work. In September 2018, Cornell determined that Wansink had committed scientific misconduct and removed him from all teaching and research positions. For over a year, the accuracy of Wansink’s research has been increasingly called into question, with five papers retracted (one of which was retracted twice), fourteen corrected, and over fifty others facing scrutiny.
This investigation was prompted after doubts were raised by James Heathers, a postdoctoral researcher at Northeastern University in Boston, who called into question the veracity of the results of one of Wansink’s most famous works after a statistical reanalysis of data from the bottomless bowls study. The study was as follows. In 2005, Wansink co-authored a paper titled Bottomless Bowls: Why visual cues of portion size may influence intake. In the experiment participants were seated at a table, each in front of a bowl of tomato soup. After eating as much as they wanted in twenty minutes, they were asked to rate, among other things, how much soup they thought they had consumed. The independent variable was that while half of the participants were seated in front of a normal soup bowl, the other two were served soup in bowls that were refilled through discrete tubing that ran through the table and into the bowls. The findings showed that people eating from the “bottomless” bowls consumed 73% more soup than those eating from normal bowls, but estimated that they ate 140.5 calories fewer than they actually ate. Wansink and his team concluded that although the participants given the self-refilling bowls ate significantly more soup, they were not aware of consuming the additional amount.7
Doubting the results, Heathers used a technique known as SPRITE (Sample Parameter Reconstruction via Iterative Techniques) to investigate whether the descriptive statistics reported in the paper could possibly exist given the setting and conditions of the experiment. These statistics include the number of data points, means and standard deviations. What he and other researchers eventually found was that Wansink had been “producing” his results through various unethical and incorrect methods.8 These problems included conclusions not supported by the data presented, data and figures duplicated across papers, incorrect statistical analyses, questionable data producing impossible values, and “p-hacking”. The latter method is the act of cherry picking results that are the most significant or interesting, and then adjusting your initial hypothesis -which is the opposite of the scientific method.9
In light of this investigation, Jean Fain, a psychotherapist affiliated with Harvard Medical School says that, “[Wansink’s tips] can be dangerous to people with diagnosable eating disorders, who, in following Wansink’s advice to a T, are more apt to ignore their internal experience of hunger and fullness, satisfaction and nourishment, and focus exclusively on externals, like plate and portion size.”10 It is important to note that while the specific results from Wansink’s studies don’t hold up, much of the qualitative methods he describes in his work to help you become more mindful eaters and the environmental factors causing mindless eating have been proven to be valid and supported by other research in the field.