Nobody likes to be shortchanged. When it comes to single-serving foods, though, some companies are doing just the opposite -- filling their packages with more food than the label states, new research shows.
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Single-serve packages of cereals, in particular, included as much as 72 percent more food than the amount printed on the package label. Mini danishes and donuts, and some cookies and crackers also offered more in the package than promised.
That's a bargain to the average consumer, but the overpacking also has implications for millions of Americans trying to control their portions.
"The reason this matters is if you're trying to watch your weight or if you're diabetic," said Joan Conway, a registered dietician and research chemist with the USDA's Agricultural Research Service.
An extra 10 to 100 calories
The differences could translate to between 10 and 100 extra calories, and 3 to 19 grams more carbohydrates in a serving, Conway said.
She and other researchers at the USDA's Diet and Human Performance Laboratory in Beltsville, Md., frequently work with precise portions and wanted to see if the single packages would be accurate enough to allow them to forego weighing portions for diet studies.
They tested about 100 different products. With such notable differences in cereals they repeated the tests, and got similar results.
National brands were tested, though no brand names were included in their findings, which were published Tuesday in the Journal of the American Dietetic Association.
The largest variation was found in "toasted grains cereal with supplement," which listed a weight of 23 grams but averaged nearer to 40, 72 percent above the printed weight. Bran flakes with raisins averaged 39 percent higher and as much as 55 percent higher in a repeat test. Toasted oat cereal was more than 18 percent higher on average.
With a bit of shopping savvy, it is possible to identify many of the tested cereals in the product lines of Kellogg's, which makes Special K and Raisin Bran, or General Mills, which makes Cheerios.
"I bet the packaging is more expensive than the cereal, so it's easier for them on their assembly line to just fill the boxes up," Conway said.
Kellogg's spokeswoman Kimberley Goode said the company tries to package cereal as close to the printed weight as possible. "We take a number of steps to minimize overage because that would add costs to our business," Goode said.
General Mills did not return a request for comment. Kraft Foods, which makes Post cereals, said most of its cereals are not sold in single-serve packages.
Federal regulations require accurate weights on food, though the Food and Drug Administration, which requires accuracy within 1 percent, focuses more on underweight samples than those with extra product. The National Institute of Standards and Technology allows for 5 to 10 percent variations.
Other foods the researchers found regularly exceeded label weights: buttery crackers averaged 15.8 percent higher; diced peaches were 8.6 percent higher; and single slices of rye bread came in over 11 percent higher.
Potential problems for diabetics
While excess food in single servings may seem trivial -- a small bonus, perhaps -- some may find it frustrating and even potentially harmful. Many dieters rely on the precise calorie and fat counts listed on labels that are derived from specific amounts of food. For the estimated 18 million diabetic Americans, especially those with type 1 diabetes, the wrong amount of certain carbohydrates in food may prompt adverse effects.
Diabetics often work with dieticians to precisely manage their portions. Mary Austin, president of the American Association of Diabetes Educators, said diabetes sufferers shouldn't worry too much about small variations in product weight, though they should keep a close eye on labels.
"The usefulness of being off a gram or two is probably not that significant, but truth in advertising is important," Austin said. "People should have a comfort level in knowing that an ounce is an ounce."
It is not the first time single-serve foods have been found to exceed the weights indicated on their labels. In 1995, New York University researchers Lisa Young and Marion Nestle found that baked goods bought in Manhattan stores were routinely larger than listed: Cookies averaged more than 20 percent larger; muffins averaged 15 percent.
The researchers in the current study found 15 foods underweight below the FDA standard, though they did not list them and none exceeded the NIST standard.
By contrast, many other foods were quite accurate, including raisins, saltines and snack chips. Individually wrapped candy and single packets of condiments like ketchup and salad dressing were especially accurate. "Condiments and candy, they sure know what they're doing," Conway said.
So were ice cream sandwiches and chocolate-covered ice cream bars.
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