As the FDA moves to finalize a rule requiring front-of-package (FOP) nutrition labels on most packaged foods and beverages in the US, new research suggests that while the proposed “Nutrition Info Box,” showing levels of saturated fat, sodium, and added sugar, was found to work best for consumers who had higher nutrition literacy, it may not be the most effective choice for all Americans. The findings from the study in the American Journal of Preventive Medicine, published by Elsevier, provide timely evidence on how FOP labels will help consumers identify healthier foods, which could ultimately support healthier eating.

Unhealthy diets are a leading risk factor for death worldwide. In the US, diet-related diseases account for over $50 billion in annual healthcare costs. Despite the well-established link between diet and health, average US diet quality remains poor. To address this major challenge, the use of interpretive FOP labels was proposed by the FDA in January 2025.

“The FDA’s internal research suggests the ’Nutrition Info Box’ label improves consumer understanding more than other label designs, and they hope it will help consumers quickly and easily identify healthier foods. We were interested in whether this label had different effects for people in different subgroups,” says first author of this study Yuru Huang, PhD, University of Tennessee Health Science Center.

To inform the FDA’s label selection in finalizing the proposed rule, investigators conducted an online randomized trial with more than 5,000 participants who were their household’s primary grocery shoppers across the US: consumers with varying levels of nutrition literacy and from different racial, ethnic, income, or education groups. Participants were randomly assigned to view foods and beverages with one of six different types of labels shown, including a label similar to the FDA’s proposed Nutrition Info label, “spectrum” labels that rated foods from least to most healthy, and other types of labels implemented internationally. Participants were asked to look at two products side by side and determine which they thought was healthier to measure how well the labels help consumers understand which products are healthier.

Nutrition literacy gap

Lead investigator Anna H. Grummon, PhD, Stanford University School of Medicine, notes, “For each of the labeling systems we measured the gap in understanding between people with higher and lower nutrition literacy—that is, how much better consumers with higher nutrition literacy were at identifying healthier products compared to consumers with lower nutrition literacy.”

They found that the nutrition literacy gap was largest when consumers viewed products with the Nutrition Info labels shown (about a 12-13 percentage point difference between groups) and smallest when the “spectrum” labels were shown (about a 3 percentage point difference), meaning those are easiest to understand for consumers of all literacy levels. “We were surprised to find that the Nutrition Info labels worked so much better for consumers with higher nutrition literacy compared to lower nutrition literacy,” says Dr. Grummon.

Principal investigator of the grant funding this study, Jason Block, MD, Harvard Medical School, emphasizes two important considerations for the FDA as it finalizes its label design. “First, if the FDA requires a Nutrition Info label, they should ensure that they also provide extensive education to consumers with lower nutrition literacy about how to use it, to ensure that all consumers can benefit from this label. Second, the FDA might consider adopting a different design other than the Nutrition Info label that avoids widening gaps in consumers’ ability to identify healthier products.”

Overall, all labels tested improved consumer understanding compared to the current status quo of voluntary (positive) or numeric labeling systems, supporting the FDA’s efforts to mandate the FOP label. The investigators point out that improved understanding does not necessarily translate to healthier purchasing or consumption. “In our previous research, we found that Nutrition Info labels did not lead consumers to choose healthier foods and beverages when grocery shopping, even though the labels helped consumers identify healthier products. In that study, the spectrum labels were the only labeling system to prompt healthier food purchases,” notes Dr. Grummon.

Dr. Huang concludes, “FOP labels may be more effective at prompting behavior change when they communicate a single, simple message and incorporate both positive and negative cues. Our results show that the label effects vary across nutrition literacy levels, which could help inform the FDA about potential disparities before finalizing its label choice.”