Brian Wansink and Collin Payne recently examined the relationship between Body Mass Index (BMI) and eating behaviors at all-you-can-eat Chinese buffets. The researchers found that customers with a higher BMI were more likely to use larger plates and to face the ever-tempting buffet. They were also less likely to use chopsticks (as opposed to a fork) or have a napkin on their lap. Wansink and Payne concluded that, “small changes in one’s environment may lessen one’s tendency to overeat.” (HT: Dmitri Leybman) [%comments]
Nudges by Chopstick
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Chopsticks slow you down. Forks are good but soup spoons are better for optimizing your calories per second.
“small changes in one’s environment may lessen one’s tendency to overeat.” Hah! This is a clear confusion of cause and effect.
Sure, there is a high correlation with one’s desire and tendency to stuff one’s face and certain behaviours prevailing. But you can’t draw the conclusion that changing one’s behaviour will reverse the effect. The more likely effect is that the high-BMI individual will eat someplace else.
There is polite classy elegant dining…and then there is eating like a pig and shoveling it in.
I intend no offence to high-BMI individuals or pigs.
Correlation != Causality
It’s time to hand the chopsticks and napkins to some fat folks and see if their BMI changes.
Couldn’t the conclusion go the other way? That a persons overall eating tendencies (and resulting BMI) are what shaped their decisions on what size plate, utensil and seating position and that if those variables were changed the overall intake would be the same.
The conclusion would then be that they need to change their eating tendencies and that will lead them to follow the lower BMI choices (small plate, chopstick, back to buffet) and not vice versa.
The environments will always exist so the change needs to occur at a personal level for those environmental changes to actually work. I am guessing if provided with smaller plates high BMI’ers would just go up more.
An interesting follow up would be to take the high BMI group and have them utilize the low BMI eating behaviors and observe if there are any changes. That would prove or disprove my guess.
Seems there conclusion might be more correlation than causation. Those who overeat use forks because it’s easier to stuff their faces and don’t use napkins because they are too busy with their food. Forcing one to switch from fork to chopsticks would likely only slow them down and not actually decrease overall food intake.
Napkins on your lap are useless if your belly is large enough to catch any dropped food – sadly I speak from experience!
I suspect that higher incomes/ educations correlate with lower BMI, napkins on laps, not cleaning plates, and chopstick-using. And that’s what they could be seeing here.
This could be simply correlation, but there is also some merit to hypothesizing that small changes may lead to reduced consumption. I use smaller plates at home because I know I’ll eat whatever I put on it, and I’m going to fill it up regardless of size, so why not use the one that’s got half the area? Same for ice cream – it goes in a small teacup or occasionally an espresso cup.
The effect in a buffet of having everyone use smaller plates and chopsticks is that it would force people to eat more slowly, by giving them a tool that is less efficient for shoveling and punctuating their servings with more frequent trips to the buffet. Thus they may start to feel full after having eaten less, simply because it takes a while to feel full and these tricks make you slow down so you’ve eaten less once the “full” feeling hits you.
If buffets switched everyone to small plates, sure – more people would take more trips to the buffet. But I bet there would be an overall small decrease in food consumption because most people wouldn’t make enough extra trips to compensate for the lost capacity of the larger plates. It would also probably help the restaurant cut down on wasted food.