The amount of food you eat is affected by the size of the
portion you get. At restaurants, for
example, people generally eat what is on their plate. So, the more food they are given, the more
that they will eat. This is a
particular problem, because obesity rates are rising worldwide. We need to find ways to help people eat less
food. Portion size seems like a great place to start.
There are lots of ways to influence portion size. At home and at buffet lines, it is helpful to
use small plates. You tend to put enough
food on a plate to fill it, so using a smaller plate leads to smaller
portions.
In addition, restaurants often offer portions of different
sizes. At high-end restaurants, for
example, steak-eaters may choose the size of the steak they order. At fast-food restaurants, there are often
specific sizes of drinks and fries that are available.
An interesting study by David Dubois, Derek
Rucker, and Adam Galinsky in the April 2012 issue of the Journal of Consumer Research suggests
that the size of a portion that someone orders can be influenced by their need
to enhance their status. The idea is
that in many situations, bigger portions are seen as reflecting higher status
than smaller portions. When people are
feeling powerless, they often want to make themselves feel better by enhancing
their status. Ordering a larger portion
is one way to do that.
The researchers started by confirming that people generally
viewed people who were eating larger portions as having higher status than
those eating smaller portions. Next,
they looked at the relationship between feeling powerless and portion
size.
In one study, participants were residents of an apartment
building. The researchers set up tables
in three different lobbies of the building.
Each table was set up to look like it was advertising a new bagel
restaurant in town that was giving out free samples. One table had a sign saying, “We all feel
powerless in the morning, treat yourself to free bagels.” One table had a sign saying, “We all feel
powerful in the morning, treat yourself to free bagels.” A third (control) table said “It’s morning,
treat yourself to free bagels.”
On the tables were two bowls with bagel pieces. In one bowl, the bagel pieces were cut in
small cubes, and in the other, the bagel pieces were cut into large cubes. People coming to the table were told to take
as many bagel pieces as they wanted, but they had to eat them at the
table. The people who were at the
‘powerless’ table were more likely to take large bagel pieces than those at the
other tables. As a result, they ate
more. On average, people at the
‘powerless’ table consumed about 100 calories worth of bagels, while those at
the other two tables consumed about 70 calories worth of bagels.
Two other experiments in this series extended the
results. One study showed that people
were most likely to order large portions when they felt powerless and were
eating in a social situation. If they
felt powerless and were eating alone, then they did not order large
portions. This finding suggests that
people are selecting portions in part based on the status that those portions
may give them.
Finally, the researchers created a situation in which
smaller portions signal higher status.
In this case, they had participants in the lab read an article
suggesting that thinner people are more likely to be successful in business
than fatter people. The experimenters
manipulated the feeling of powerlessness by having people imagine either that
they were an employee who had to do what their boss wanted them to do (a
powerless position) or that they were a boss who could tell their employees
what to do (a powerful position). At the
end of the study, participants were able to select from among different sizes
of Toblerone candy bars. In this study,
participants who thought that being thinner conveyed higher status selected smaller candy bars when they felt
powerless than when they felt powerful.
Putting these findings together, then, it seems that in
general people think that larger portions convey more status than smaller
portions. As a result, people may
overeat in order to increase their status compared to other people.
If we ant to help people to eat less food, then there are a
few things we can do. First, these
studies suggest that we can help people to see that being thin can also convey
status. In that case, the need to show
status can actually get people to select smaller portions. Second, people who are concerned about their
portion sizes should focus on the aspects of their life in which they have
control in order to minimize the need to show status through food.