A 16-year study on the effects of “front of package” (FOP) nutrition labels on Food products suggests a correlation between the optional labels and the quality of nutrition within those foods, along with the foods of their competitors.

Researchers at North Carolina State University analyzed 21,096 products from more than 9,000 brands in 44 food categories from 1996 to 2011 to determine the impact of putting nutritional information like calories, fat, sodium and sugar on the front label of food and beverage products.

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FOP food labels are currently voluntary in the food industry, though many major brands have adopted the labels in addition to the more common and FDA-required “nutrition facts” often seen on the back or sides of food packaging. For this study, the researchers looked at the “Facts Up Front” style of label, which often showcases specific nutritional criteria.

“For consumers, we found that the presence of a Facts Up Front FOP label on a package generally meant that the product had a better nutritional profile than competing products that didn’t have an FOP label,” said Rishika Rishika, study co-author and an associate professor of marketing in North Carolina State University’s Poole College of Management, in a press release.

The researchers focused on two criteria: how certain Food Categories Changed over the years after at least one product adopted the FOP labeling, and how certain food categories changed (or didn’t) when none of the products in the category adopted the labeling.

When the categories in which some products Adopted Fop Labeling are considered together, there was a noticeable drop across them for the type of negative nutrients singled out by FOP labeling. Sugar went down almost four percent, and fat, salt and calories all declined between 12 and 13 percent.

Rishika explained this as a case of “competitive pressure on other brands in that category to innovate and improve the nutritional quality of their products.”

The results indicated that, in general, food that adopted FOP labeling showed improved nutritional quality with premium brands and products in categories that are “broadly unhealthy,” such as snack foods, demonstrating more pronounced improvements in nutrition.

More broadly, the findings suggest that voluntary, highly visible nutritional labeling can be an effective tool for encouraging change on an industry level.