How Portion Size Adds Up to Obesity

Half-pound muffins? Two-pound pasta bowls? Since the 1970s, American fast-food and sit-down restaurants alike have contributed to the obesity epidemic by serving individual people enough food for a small family.


Portion Size and Obesity: How It All Adds Up
In competition with each other and operating under the philosophy that bigger is better, restaurants often serve up a portion size that is equal to two to four normal servings, while menu boards at fast-food restaurants scream “supersized burgers and fries!” Consider these portion-size facts:

• In the 1950s, a regular fast-food burger was 2.8 ounces and 202 calories. In 2004, that same burger was 4.3 ounces and 310 calories.
• A regular Coke grew from six ounces in 1916 to 21 ounces in 1996.
• These days, you can buy a “double gulp” drink that’s 64 ounces and more than 600 calories, and a burrito that’s 1,100 calories or almost three-fourths of the entire daily 1,600-calorie allotment for an average-sized, non-exercising woman. Have them both, and you’re over the allotment.

Portion Size and Obesity: Retake Control
Of course, nobody stands over us, making us eat. But food psychology being what it is, we do it anyway.
“There’s quite a body of research out there that has proven no matter how you serve the food — whether in a bowl, a cup, a plate — the more you’re served, the more you’ll eat,” says North Carolina State University professor and nutrition specialist Carolyn Dunn, PhD, chair of North Carolina’s Eat Smart, Move More initiative. “It doesn’t matter how hungry you are or what you ate earlier, you generally eat more than you need to if it’s put in front of you.”

In one of several studies on portion size and consumption, 180 adults were served either a 9-ounce or a 13-ounce portion of macaroni and cheese at a restaurant. The adults who were served the 13-ounce portions ate 43 percent more — for an additional 172 calories — than did the adults who were given the smaller portions. Such research results lead nutritionists and food psychologists to talk about “unit bias” — that is, the consumer’s psychological need, no matter the hunger needs, to consume whatever unit is served, be it a 9-ounce portion of macaroni and cheese or a 13-ounce portion.


Portion Size and Obesity: The Government Steps In
Nutrition experts know portion size isn’t the only reason 65 percent of Americans are overweight or obese, and it isn't just a problem when dining out. But increased portion size is a major contributor to the obesity epidemic and one reason why women consume over 335 more calories per day than they did in 1971, and men, 168 more calories per day. And nutritionists believe restaurants, where Americans spend half their food dollars, set the norm for what constitutes a satisfying plate of food at home.
The good news is that nutritionists and public health agencies, even state legislators and public policy makers, are on to us. Individual states have created awareness campaigns around the causes of obesity, including portion size. Policy-makers in California and New York City are enacting and implementing calorie-disclosure initiatives, requiring some restaurants to publicly display calories on menu items.
The battle against portion size is supersized, says Dunn. People don’t want to hear they need to step away from the table, and appetite is a difficult desire to regulate. But the message is slowly catching hold as consumers begin to understand the seriousness of the obesity epidemic and their power over their own diet.
“Anecdotally, I overhear people — friends and family — saying ‘That’s too much. That’s a huge portion,’” says Dunn. “I think slowly we will swing the pendulum — for this and all the other behaviors as well.”