Watching Waiters' Weights

Source: Creative Commons

I love behavioral science research that’s conducted “in the wild”, especially if it involves food. In many cases, studies are delightfully simple. In some cases, they are simply delightful.

Here’s a taste (sorry!) of brand new field experiments that show how we can be influenced to make better – or worse – choices about what we eat.

Location, location, location

Since many of our food choices are relatively mindless, behavioral science suggests that introducing small changes to the environment in which decisions are made can have big effects. One of the oldest tricks in the book that shops already use is about the physical location of products (such as candy bars at the checkout).

A study by Floor Kroese and colleagues at train station snack shops in the Netherlands tested the effect of having healthy (test store) instead of unhealthy snacks (control store) at cash register displays. On average, 23 ‘nudged products’ were sold each day in the control store, whereas this number was raised to 41 in the test store – that’s 78% more. In a third store, adding a sign near the display that read ‘we help you make healthier choices’ decreased this difference somewhat, but customers who were aware of being nudged still purchased 52% more of the healthy items.

Bring it forward

It’s conventional wisdom and an established empirical fact that people make healthier decisions when they are in a cold state (e.g., not hungry) or when they are planning for future rather than immediate consumption. Eric VanEppsat and fellow researchers at Carnegie Mellon conducted field studies at cafeterias. In one of their experiments, staff at a large company were randomly assigned to either place orders in advance (before 10am) or at lunchtime (after 11am). People in the advance order group ordered lunches that were 30 calories lower on average (approximately 5% of lunch calorie content for this sample).

The authors of this study reckon that behavioral interventions to promote healthy eating do not have to restrict consumers’ choices. Encouraging consumers to choose meals in advance could yield significant benefits.

The waiter’s weight

Whether it’s in stores, at home or in restaurants, our decisions are unconsciously influenced by a range of cues. Tim Döring and Brian Wansink at the Food and Brand Lab at Cornell University looked at hundreds of interactions at 60 different restaurants. Observers noted down their estimated body mass index (BMI) of both the diners and waiters, as well as how much food and drink was ordered.

Their findings show that diners are four times as likely to order desserts when the waiter has a BMI higher than 25. These results don't change significantly when other variables are taken into account, such as diners’ own BMI, as well as ethnicity, gender, and age.

The implication? Once again, healthy choices are a matter of timing. When you next go to a restaurant, make sure you decide what to order before the waiter arrives.