Going back for seconds at all-you-can-eat Chinese buffets

Getting more than one helping of food is obviously a draw for patrons of all-you-can-eat restaurants.   But can one predict how many trips to the buffet a particular diner will make?  Does scoping out the buffet before grabbing a plate lead to more trips?  How does sitting in a chair that faces the buffet influence those second or third helpings?

Researchers with Cornell University’s Food and Brand Lab have been exploring these questions using 30 trained observers staked out in buffet restaurants in six states.  Some of their findings are presented in the current issue of the American Journal of Preventative Medicine.  They observed 303 diners (systematically selected) at 22 all-you-can-eat Chinese buffet restaurants.   The observers looked for specific dining room behaviors in the 165 male and 158 female patrons, such as:

  • scouting the buffet versus serving themselves immediately
  • using a large plate versus a smaller one
  • using a fork versus chopsticks
  • facing toward the buffet or away from it
  • placing a napkin on their lap versus leaving it on the table

The observers also estimated the patrons’ height and weight, and used the Body Image Assessment for Obesity to assign a body-mass index score to each subject.  Here’s some of what the authors reported:

  • Those who served themselves immediately took 2.76 (mean) trips to the buffet compared to 2.35 (mean) trips among those who perused the offerings before filling their first plate.
  • Those who used larger plates made 2.64 (mean) trips to the buffet compared to 2.07 (mean) trips among those who chose a smaller plate.

Moreover, after controlling for the estimated BMI for each patron, the results remained statistically significant.  That is, the association was not simply a result of people with higher estimated BMIs making more trips to the buffet.

This study, along with the dozens of others conducted by Cornell University’s Food and Brand Lab, help us better understand how environment features and our own behaviors affect consumption, and potentially obesity.  The lab’s director, Brian Wansink, PhD, is a consumer psychologist and the author of Mindless Eating: Why we eat more than we think.  Wansick and his colleagues have examined how catchy names (e.g., Silly Dilly green beans, x-ray vision carrots) can increase school children’s selection and intake of vegetables, and how visual cues can act like stop signs to control overeating.

Back at the all-you-can-eat-buffet, Wansink offers a couple of recommendations.  They aren’t directed at the diners themselves, but are consistent with his focus on the environment in which people eat.  He suggests that buffet owners use smaller plates and place them behind the buffet.  Diners will be compelled to review the food offerings before they get their plate.  The added benefit he notes: if patrons don’t overeat, buffet owners will save money on food costs.