Smaller Portions at Restaurants: What Consumer Behavior Says

Experts in weight and human behavior are looking at ways to help society change eating habits for the better. They’re working with a few basic principles of human nature including that people, for the most part, stick with the ‘default option’. For instance, data shows that organ donor rates differ significantly if a country has an opt-in organ donation versus opt-out program. Whatever the default is – donate your organs or do not donate – the vast majority of people stick with that default. Another principle is that we tend to be very sensitive to social norms: research has shown that the number of people who reuse towels at hotels increases by 26 percent when the hotel puts up a sign saying “a majority of guests in this hotel reuse their towels”. That increase jumps to 33 percent when the sign says “the majority of hotel guests who stayed in this room reuse their towels”.

At the Obesity Society’s 2012 scientific meeting, Darren Siefer – a food and beverage industry analyst – gave a talk about how we can apply our knowledge of consumer behaviors, to influence people to choose smaller portion sizes and select healthier food options.

The focus of the talk was an interesting experiment at the popular restaurant chain, Panda Express. Seifer said data shows that in restaurants, people are less likely to order a menu item if it’s labeled ‘healthy’, probably because they have an expectation of that food being less rewarding. However, if changing food is a particular challenge, decreasing portion size may be a good target because it does not require someone to make a different food choice.

Survey data showed that 37 percent of people say that the portions are ‘usually too large’ at restaurants they visit; yet, almost 90 percent of people never request a smaller portion. Half of people said that if a restaurant offered smaller portions, they would choose that at least some of the time.  For their experiment, Seifer’s group watched customers for several days to see if anyone spontaneously for a smaller portion size at Panda Express. Next, they had the servers ask each customer: “Would you like to cut more than 200 calories off your meal by taking a half-portion of side dish?” (no discount was given). The final phase of the study involved the same half-portion side dish question, but with a small discount of $0.25.

They found that a very small number of patrons spontaneously asked for a smaller portion: about 1%. When the server asked if they’d like a smaller portion, about 35% accepted. This number was the same whether or not a small discount was offered, indicating that the discount made no significant difference in the decision. The important questions became: did taking the smaller portion actually reduce the amount eaten, or do the people who take the larger portion just have more left-overs? To answer this, the researchers weighed the food thrown away after the meal and found that those who picked the smaller portion threw away the same amount of food as customers who refused or weren’t offered the option.

The researchers concluded from the experiment that people won’t ask spontaneously for smaller portions, but a significant number will accept nudges to do so. And, importantly in terms of obesity control, people did not compensate by eating more of other foods, like their entree in the Panda Express experiment. The findings suggest that it may be worthwhile to take measures to make it easier for servers to offer ‘downsizing’. He called side dishes great targets for portion control, because they are often considered more ‘boring’ than the entree, but are high in calorie value (for instance, white rice or fried rice at Panda Express).

We asked Dr. Mona Misra of Beverly Hills for her thoughts on this presentation. She said, “It is always great to see research on obesity prevention strategies. This is a fascinating study on human behavior in regards to portion sizes when eating out. Restaurants have created a culture where ‘bigger is better’ and there is more value perceived when larger portions are served. But in truth we need to remember that eating larger portion sizes does not add value to our health which is much more important.”

“The fundamental message is that if people are served smaller portions, they’re satisfied and ultimately eat fewer calories,” Dr Misra said. “So anything that we can do to reduce the portion sizes served to people is an important tool to help to prevent obesity. It is surprising and encouraging to see that over a third of people will voluntarily reduce their portion sizes when given very little provocation to eat healthier. We need to create an environment where we encourage people not to increase portion sizes or ‘super-size it’ but to decease portions and ‘healthi-size it'”.

Related Reading:
Also presented at The Obesity Society Annual Meeting, new research shows how the perception of portion size can influence hunger hours later. You can read more about the talk here.

by Emma Squillace
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