The amount of food you’re served influences how much you eat more than what the food tastes like. That’s the conclusion from researchers who looked at how much stale popcorn people ate when given different-sized amounts. Although we might like to think that the main influences on how much we eat are the food’s flavor and how hungry we are, many studies say this view is false.
By understanding how important portion size is, you will be better able to eat less to lose weight or increase your consumption of healthful foods like fruits and vegetables.
In his most recent look at the impact of portion sizes on people, Brian Wansink, Ph.D., a professor at Cornell University, gave moviegoers free popcorn. Some got fresh popcorn, while others received stale two-week-old popcorn. People were given either a medium or a large bucket. Those with the old popcorn definitely noticed the poor taste and described it as “stale” and “terrible.”
But the taste didn’t stop them. Those with large containers of stale popcorn ate 34 percent more than those with medium containers. For those with better-tasting fresh popcorn, a large container increased consumption by 45 percent. When people were asked if the big buckets influenced how much they ate, the vast majority denied that it had any effect. They claimed they would have eaten the same amount from a medium-sized bucket.
Past research suggests that these people are mistaken. Research at Pennsylvania State University has repeatedly shown that people eat more when served larger portions. For example, when people were given different amounts of macaroni and cheese at lunch, those offered twice the amount of the smallest serving ate 30 percent more.
People with more food in front of them ate more, whether the food was served to them on plates, or they served themselves from a serving bowl.
Start with smaller amounts
In another study, researchers gave men and women different-sized submarine sandwiches on four consecutive days. When given a 12-inch sub, people consumed 31 to 56 percent more calories, compared to the day when they ate a 6-inch sub. While people reported feeling some differences in hunger and fullness after these two meals, they reported no difference in satisfaction after an eight-, ten-, or twelve-inch sub, despite eating more.
These studies suggest that paying attention exclusively to your internal hunger signals is an ineffective way to eat less. If you want to cut back on how much you eat to lose weight or prevent mid-life weight gain, you should start with smaller amounts of food. For example, serve yourself a portion three-fourths of the usual size and plan to go back for more if you’re still hungry. You may not need any more, however. This method of portion control will be even easier if you don’t eat with serving bowls in front of you.
If you eat out, put half of the giant portions restaurants usually serve in a take-out container as soon as the food arrives. You could also piece together a meal with less food by selecting two or three small dishes like a soup, salad, appetizer, or vegetable side instead of an entrée. Another option is to split an entrée with a companion and order a soup, salad, or vegetable side dish to round out your meal.
Although research on the impact of portion size can help you eat less, it can also help you meet the good health goal of consuming seven to 10 servings of vegetables and fruits a day.
If a larger portion size makes people eat more stale popcorn, the same principle will encourage you to eat one or one-and-a-half cups of vegetables, which is two to three servings. But don’t serve old, limp and tasteless vegetables and fruits. Experiment with a variety of ways to make salads and cooked vegetables flavorful and enjoyable. Then put a big bowl with enough for double or triple servings on the table. Even if there are leftovers, which are great for vegetable soup, you’ll come closer to the goal of seven to 10 servings than if you set out less.
Nutrition Notes is provided by the in Washington, D.C.