Food for Thought on Healthy Dietary Guidelines

Food for Thought on Healthy Dietary Guidelines

Behind the government’s myriad figures on serving sizes, calorie counts and recommended daily servings

By Jo Craven McGinty in the Wall Street Journal

American consumers have been confused by the concept of serving sizes for decades, and the federal government is partly to blame.

Is a serving of pasta 1 ounce or 2? Is a helping of peanut butter 1 tablespoon or twice that amount?

The answers depend on whether you are reading the dietary guidelines published by the Department of Health and Human Services and the Department of Agriculture online and on educational posters, or the Food and Drug Administration labels printed on food packages. They don’t match up.

If that isn’t frustrating enough, the government keeps changing its mind about what constitutes healthy eating.

The latest turnabout took place last month, when the Dietary Guidelines Advisory Committee declared that cholesterol and certain fats—once considered the bane of a healthy diet—aren’t so bad after all. Coffee and alcohol in moderate doses are also OK, according to the committee, whose recommendations will contribute to the 2015 Dietary Guidelines for Americans to be completed this year.

Here’s a primer on what the government’s dueling serving-size numbers actually try to communicate, and why.

The USDA and HHS dietary guidelines, as the name implies, aim to give consumers advice on what they should eat. They are revised every five years based on a review of the latest medical and scientific research by an advisory committee of outside experts. The resulting guidelines tell consumers how much to eat from each food group in a day to meet nutritional needs for good health.

The FDA serving sizes printed on packaged foods, by contrast, are supposed to reflect how much consumers really eat, but the amounts are based on survey data collected in the late 1980s. Americans eat more than they used to, and the labels no longer accurately reflect consumer behavior.

Here’s how this situation came about. Until the 1950s, USDA and HHS dietary guidelines didn’t clearly define serving sizes. In response to criticism, they developed measurements, defining a serving of fruit or vegetables as half a cup, a serving of grains as 1 ounce, and a serving of meat as 2 to 3 ounces.

But visual guides published for consumers continued to express most of the recommendations as daily servings. In 1992, for example, the Food Pyramid recommended 6 to 11 servings or bread, grain or pasta each day.

The problem was, people identified a serving as the amount of food on their plates, and it wasn’t clear from the pyramid that 1 serving was intended to equal 1 ounce. By that measure, about 3 cups of pasta would total 6 servings—the entire daily recommendation for many people. A half cup of pasta weighs about 1 ounce.

In 2005, the USDA and HHS dietary guidelines, seeking to end the confusion caused by the word “serving,” published new daily recommendations according to specific measurements, including ounces, cups and teaspoons, depending on the food. With this approach, the daily recommendation for bread, grain and pasta, was recorded as 6 ounces rather than 6 servings for a 2,000 calorie diet.

“One muffin the size of your head, one bagel or one bowl of pasta is a 6-ounce equivalent,” said Lisa R. Young, a nutritionist and professor at New York University who studies portion sizes. “No one understands this stuff.”

The current USDA and HHS dietary guidelines augmented this information by abandoning the pyramid in favor of a visual portrayal of a dinner plate, divided among the major food groups to emphasize the recommended quantities in relationship to each other. Fruits and vegetables together cover half the plate. Protein—meat and poultry for most people—occupies less than a quarter of the space.

“The plate was a huge step forward in really giving people education on what proportions are expected to come from fruit and vegetables, whole grains, and animal protein sources,” said Rafael Pérez-Escamilla, a professor at the Yale School of Public Health and a member of the Dietary Guidelines Advisory Committee.

FDA food labels include nutrition information to help consumers compare similar products, but FDA serving sizes are not recommendations.

Because the FDA’s food labels tell consumers how much they tend to eat from a bag, box or can, rather than how much they should eat, some FDA servings are double the size of those suggested by the USDA and HHS—and they are about to get bigger. The FDA is in the process of updating the labels to reflect the larger portions Americans now typically eat.

When the new labels are implemented, the FDA serving size of ice cream will increase from a half cup to a full cup. The serving size for a muffin will increase from 85 grams to 110 grams. And products that are typically consumed in one sitting—a 20-ounce bottle of soda, for example—will no longer be labeled as more than one serving.

“That’s created some controversy,” said Mary Poos, acting director of the FDA’s Office of Nutrition, Labeling and Dietary Supplements. “Some people say we shouldn’t make them bigger because people will eat more.”

FDA labels also include nutrition information for the serving sizes printed on the labels to help consumers compare the nutritional values of similar products.

But to get a full picture of what the government tells us a healthy diet looks like, and to help reduce the confusion about how much and what we should eat, consumers should consult the USDA and HHS dietary guidelines. Online resources provide tools to track eating and to create a personal nutrition profile based on age, gender, physical activity, height and weight.

It’s a good gut check for assessing the health of your daily diet.