The idea behind putting the familiar Nutrition Facts panel on food packaging was that informed consumers would make healthy food choices.

The fact of the matter, however, is that many Americans simply cannot understand trans fat content information — one of the most important parts of the Nutrition Facts panel.

The researchers found that more straightforward product claims, such as "low in trans fat" or "zero trans fat," were understood by consumers.

According to a new study by researchers at the University of Arkansas, unless they have been specifically educated about trans fat, consumers routinely misinterpret the information provided on the panel.

"We found that in the absence of general knowledge about trans fat, especially without a specific understanding that 4 grams of trans fat is high, even motivated consumers — that is, those who consult the Nutrition Facts panel on food packages and want to know more about the food they eat — appear to misinterpret the meaning of trans fat information," said Betsy Howlett, professor of marketing in the Sam M. Walton College of Business, "In other words, nutritionally motivated consumers lacking appropriate prior knowledge make inappropriate product judgments. This is a troubling, unintended consequence of the current trans fat disclosure on the Nutrition Facts panel."

The FDA added trans fat content to the Nutrition Facts panel in 2006. Trans fatty acids — found in many fried foods and baked goods — have no nutritional upside, but they do have a downside: increasing levels of low-density lipoprotein (also known as LDL, the "bad cholesterol"), which is highly associated with heart disease.

Unlike other panel categories, such as cholesterol, total fat and saturated fat, trans fat is not given a percentage of recommended daily value. This appears to create confusion among consumers. Take, for example, a food item that has 4 grams of trans fat. When compared to ordinary levels of fat and saturated fat on a Nutrition Facts panel, this might appear low. In fact, the opposite is true; 4 grams of trans fat represents approximately 70 percent of the maximum recommended daily consumption for the average adult.

The researchers found that more straightforward product claims, such as "low in trans fat" or "zero trans fat," were understood by consumers.

"For motivated consumers, these claims can directly offer interpretable information that the product is low in trans fat, which influences intentions," Howlett said. "In contrast, high levels of trans fat in the Nutrition Facts panel alone — without the percentage of daily value information or other clarifying information — were misinterpreted and led to a negative outcome."

These findings were published in the May, 2008 Journal of Public Policy & Marketing.