Do nutrition warning labels work?

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Jess Craig is a fellow at Future Perfect covering global health, science, and world news. You can read more of her work here.

After decades of lobbying, the US government has finally started taking action to warn consumers about the hazards of ultra-processed foods: your potato chips, granola bars, cereal, frozen pizza, even many types of store-bought bread.

As I reported last year, there is mounting scientific evidence linking such ultra-processed foods, or UPFs, to disorders that range from obesity, diabetes, and high blood pressure to depression, anxiety, and autoimmune disorders. Precisely what is classified as a UPF isn't perfect and the category can sometimes be too broad, as my colleague Marina Bolotnikova explained in December, but there's still a growing consumer desire for clarity about what we're buying and eating.

Earlier this year, in an effort to combat the rising burden of these chronic diseases, the US Food and Drug Administration (FDA) under former President Joe Biden proposed a new policy that would require food producers to add new nutrition labels to the front of most packaged foods, warning consumers about the high fat, sodium, and sugar content typically found in UPFs. New Secretary of Health and Human Services Robert Kennedy Jr., will likely continue this work; he has called UPFs "poison," and has promised reform.

A handful of countries in Latin America and Europe have already introduced similar front-of-package nutrition labels. In 2020, Mexico passed a law that required a variety of warning labels on all packaged foods and beverages; the labels include black stop-sign shaped figures that indicate if the product has excessive sugar, sodium, or saturated fats. Chile was the first country to pass such a law back in 2012. The UK has a similar system in place, but companies are not legally required to add the warnings to their products.

The US may be late to the nutrition-warning game, but the good news is that similar efforts in other places have been effective in raising consumer awareness of UPF's nutritional hazards and in pressuring manufacturers to make healthier products. These labels enable consumers to make more informed decisions about what they eat without infringing on their rights to eat what they want. But while nutrition experts have welcomed the FDA's proposed policy change, the addition of warning labels to packaged goods hasn't been shown to reduce the very real burden of chronic diseases. For that, we'll need systemic change.

Jeffrey Greenberg/Universal Images Group via Getty Images

Are warning labels effective?

Much of the real-world evidence describing the impact of front-of-package nutrition labels comes from Latin American countries. They have long been pioneers in UPF research and regulation, in part because of their high burden of chronic diseases linked to UPF consumption but also because of how the spread of UPFs pushed out traditional foods, explained Vanessa Couto, a public health nutrition researcher at the University of São Paulo in Brazil.

In some 30 Latin American countries that have added front-of-package nutrition warnings, public health researchers have found that well-designed labels can help consumers be more informed about what's in the products they buy. "We see people shifting toward healthier options, avoiding less healthy options," explained Marissa Hall, an assistant professor at the University of North Carolina Gillings School of Global Public Health. "We also see where labeling can help people understand what's in their food and which products are high in nutrients of concern."

One 2024 study of almost 3,000 households in Chile found that consumers purchased significantly fewer products labeled as high in sugar, calories, sodium, and fat, amounting to an estimated 36.8 percent reduction in sugar consumption, a 23 percent reduced calorie intake, a 21.9 percent reduction in sodium, and a 15.7 percent drop in saturated fat consumption.

But not all studies report these impacts. Another study in Brazil found that while a "Warning: ultra-processed food" label significantly improved the ability of consumers to identify what products were UPF, it did not influence their purchasing intentions or perceptions of healthfulness.

The other benefit of nutrition labels on packaged foods is that it creates a market pressure for UPF manufacturers to make healthier foods, Hall explained. After Chile implemented its warning label law, the proportion of UPF products that were high in sugar dropped from 80 to 60 percent while products high in sodium dropped from 74 to 27 percent.

Similar schemes in New Zealand and the Netherlands that allowed companies to display a logo indicating a product's healthfulness if it met certain nutritional requirements also prompted companies to swiftly reformulate products. One study found that there was a 61 percent reduction of salt in cereal products in New Zealand while 20 percent of products were reformulated in the Netherlands after the labeling schemes were introduced.

The FDA's proposed nutritional labels aren't the same as those used in Latin America. In Chile and Mexico, companies are required to use bold, black stop-sign shaped icons on the front of a package, which communicate whether the product is high in fat, sugar, or sodium. If a package has three stop signs, then it is high in all three.

The FDA's version consists of small, black-and-white boxes similar to existing nutritional facts boxes that already appear on the back of packaged foods, though they'll be placed on the front. These boxes will indicate if a product contains low, medium, or high levels of saturated fat, sodium, and added sugar.

So the US labels could show that a product is high in salt but low in sugar and then leave it to the consumer to decide if that is good or bad. Contextualizing percentages can be helpful, but comparing such trade-offs isn't always intuitive. "I'm concerned that it might be confusing for people to understand an overall product's healthfulness when they're making sense of all these different nutrients," Hall said.

Others have been far more critical of the FDA's proposed nutrition labels. Sen. Bernie Sanders said the labels were "pathetically weak and must be substantially improved." He suggested that UPF warning labels should more resemble the FDA-mandated warning labels on cigarettes that explicitly state smoking causes fatal lung disease, heart disease, cataracts, bladder cancer, and a list of other conditions. (Earlier this year, a federal judge in Texas blocked an FDA mandate to require graphic warnings of smoking's health risks.)

While warning labels improved consumer awareness in studies, this hasn't translated into overall improved health outcomes. Chile introduced nutrition warning labels in 2012, but obesity rates have continued to rise from about 68 percent in 2010 to 79 percent in 2022. The Chilean government even introduced other measures to reduce UPF consumption; for example, by increasing the tax on sugary beverages from 13 percent to 18 percent in 2014.

In Mexico, which introduced labeling mandates in 2020, childhood obesity rates dropped slightly from 38.2 percent in 2020 to 37.3 percent the following year, but the number of people with diabetes increased from 15.7 percent in 2020 to 18.2 percent in 2022.

It may simply be too soon for public health officials to observe improvements in obesity and other chronic disease rates. What's clear is that we will need more than nutrition labels to create a food environment that allows everyone to eat healthy nutritious foods.

What more needs to be done to "make America healthy again"

While studies in Latin American countries have reported that front-of-package warning labels on UPFs are effective at improving awareness among consumers, this is really only one small step in the right direction. To actually reduce UPF consumption and improve health, we would need true systemic change.

More than 20 million Americans live in food deserts without consistent access to healthy foods. These areas tend to be low-income and rural communities where there is a shortage of food retailers and a lack of transportation to get there. Unprocessed or minimally processed foods are, on average, more than twice as expensive as UPFs per calorie, according to one study.

True success would require improving health education in schools, raising the quality of school lunches, and ensuring that everyone can actually afford fresh, healthy foods — a tall order in a country that has long prioritized profits over health and safety.

It remains unclear what might happen to the FDA's proposed legislation under the Trump administration. Kennedy seems keen to take on UPFs as part of his Make America Healthy Again crusade — he currently wants the FDA to ban certain additives, dyes, and chemicals currently used in UPF.

What do experts recommend? Aside from mandating warning labels on packaged goods, the FDA needs to also regulate other marketing claims that UPF companies make on their products, Hall argued. For instance, many products claim to be "100 percent all natural," which Hall's research has shown makes many consumers incorrectly assume the product has no added sugars. But this can be false because there is no standard or even legal definition of "natural."

Nutritional labels on UPF, along with other policy changes such as banning certain food dyes, is just the beginning. "It takes small steps," Baker said. And while she and many are hopeful that Kennedy's "food is medicine" outlook will usher in change, many fear that the Trump administration's federal staff and budget cuts will hamper efforts.

—Jess Craig, fellow

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