Review of Traci Mann’s Secrets from the Eating Lab, winner of the 2016 SPSP Book Prize
Nicholas Epley (University of Chicago)
Stanley Milgram surely never imagined he was laying the groundwork for healthy eating when he sat his participants in front of a shock generator. Nevertheless, the major insight from Milgram’s work—that people can underappreciate the power of a person’s circumstances in shaping behavior—is on full display in Traci Mann’s excellent book, Secrets from the Eating Lab.
As with obedience, our intuition suggests that eating is primarily about person’s character and only weakly about the circumstances that person is in. Willpower is considered to be the essential tool, and those who are overweight are stigmatized with character defects by neighbors, friends, and even doctors. Mann’s experiments on eating, conducted over the course of two decades, highlight the complex interplay between character and circumstances in order to calibrate our intuitions and identify more effective for changing behavior.
Mann first describes the history of dieting research in a way that even nondieters will find fascinating. In short, diets don’t work because they fundamentally misunderstand both human biology and psychology. Reducing calorie intake triggers homeostatic mechanisms that serve to regain weight back to a relatively stable set point. Interestingly, these mechanisms work to keep people from gaining weight as well. In one experiment using extremely well fed prison volunteers, those asked to eat 10,000 calories each day lost the weight they gained very shortly after the experiment ended. Not only is it hard to keep weight off, it’s also hard to keep it on. Mann then goes further to explain exactly why diets don’t work, and why you should stop trying them. “At worst,” Mann writes, “dieting can be hazardous for your mental and physical well-being. At best, it is ineffective and unpleasant.” Anyone who’s ever been on a diet will be happy to hear that they can stop this nonsense.
What is a person who wants to be at a little healthier weight to do? This is the point at which personality and social psychology can be at its best, and it’s where Mann’s book really shines.
Instead of trying to regulate your weight by relying on willpower and dieting, Mann uses basic psychological science to describe how to regulate your weight more wisely by using 12 “Smart Regulation Strategies.” These generally involve the same kinds of solutions that Milgram identified for changing obedience: alter your circumstances. My favorite is the first one: “Create obstacles.” You’ll eventually eat food that’s in your house, so it’s best if unhealthy food isn’t in it. If it is, it’s best to store the cheesecake out in the garage where you’ll eat if you really want to, but you’re unlikely to eat it mindlessly while making your coffee in the morning. Presenting these strategies allows Mann to describe some of her own brilliant experiments, such as one in which school children ate more vegetables when their cafeteria trays included pictures of vegetables at the bottom of each little compartment. Mann’s clever experiments show any student of social psychology how to conduct experiments that are simultaneously interesting, memorable, and useful.
Einstein once wrote, “the whole of science is nothing more than the refinement of everyday thinking.” Mann’s book provides critical refinement to our everyday thinking about eating. Instead of only focusing on your character, also consider changing your circumstances. The message is ultimately uplifting because, as Mann writes, “your circumstances are things you can change.”