Some groups want to label foods that contain anything created with modern genetic modification. Yet the previous generation of genetically modified foods, using mutagenesis, can be labeled organic. And why not label all pesticides used on food, whether synthetic or organic, if awareness is important? If a Bt genetic modification is important to know about, why isn't Bt spray on organic food important to know about.

The only thing less valuable than most proposed labeling changes are the existing labels, according to a new paper - at least if the goal is improving nutrition. 

Yet nutrition labeling can be saved, according to a paper in the Annals of the New York Academy of Sciences. The authors compared four different labeling systems and found that the Nutrition Facts label currently required on most food products in the US and Canada was least usable. That label, which lists the percent daily value of several nutrients, took more time to understand and led to nutrition choices hardly different from chance. Another label type, NuVal, enabled quick and nutritious choices. NuVal is a shelf sticker used in some American food markets, which indicates the overall nutritional value of each food item with a number from 1-100.

Resolving "nutrition conflicts"

"Food shoppers typically have a limited amount of time to make each food choice, and they find the Nutrition Facts labels to be confusing and difficult to use," says Peter Helfer, lead author and PhD student in Psychology and Neuroscience at McGill University. "One product may be low in fat, but high in sugar, while another product may be just the opposite. Nutrition Facts labels can highlight nutrition conflicts but fail to resolve them. Even educated and motivated shoppers have difficulty picking out the most nutritious product with these labels." 

NuVal scores are calculated by nutrition experts at several universities, including Yale, Harvard, and Northwestern, and emphasize both the positive and negative aspects of each food. By reducing nutritional content to a single number, NuVal labels resolve nutrition conflicts.

Two other labeling methods produced mixed results. The Traffic Light system used in the UK allowed for a bit more nutritious choices than chance. But it took more time to use, because the colors of several traffic lights have to be counted and compared. Labels that certify some foods as nutritious, but not others, are used in Denmark, Sweden, and Canada. These allowed quick decisions, but did not increase nutritious choices.

"Such certification labels are not sufficiently discriminating to produce consistently better nutrition. They also create controversies about exactly where to draw the line between nutritious and harmful foods," says co-author Thomas Shultz, Professor of Psychology and Computer Science at McGill.

The widespread availability of low-nutrition, high-calorie food is believed to be an important cause of an epidemic of obesity and associated diseases throughout the world. Shultz argues that "Empowering consumers to make healthier food choices with valid and useful nutrition labeling could help to stem this epidemic. If consumers have the information to make nutritious choices, this could nudge food sellers and producers to improve their products."