FDA bans Red No. 3, but experts warn of ongoing gaps in food safety regulations

The Food and Drug Administration announced last week that it will revoke authorization for FD&C Red No. 3 in food and ingested drugs under the Delaney Clause of the Federal Food, Drug, and Cosmetic Act. Red No. 3, a synthetic food dye, gives products like candies, frosting and frozen desserts their bright, cherry-red color.

The decision follows a 2022 petition and studies showing cancer in male rats exposed to high levels of the dye. While the cancer-causing mechanism is specific to rats and does not occur in humans, the Delaney Clause prohibits the FDA from approving additives shown to cause cancer in humans or animals, regardless of exposure levels.

“The Delaney Clause, enacted in 1960 as part of the Color Additives Amendment to the FD&C Act, prohibits FDA authorization of a food additive or color additive if it has been found to induce cancer in humans or animals,” the agency wrote in a Jan. 15 statement. “This is not the first time the agency has revoked an authorization based on the Delaney Clause.”

In 2018, for instance, the FDA withdrew authorization for certain synthetic flavors—including benzophenone, ethyl acrylate, and eugenyl methyl ether—used to mimic flavors like mint, cinnamon and citrus in processed foods.

Food and drug manufacturers who use Red No. 3 in their products will have until January 15, 2027, or January 18, 2028, respectively, to reformulate their products.

Public health advocates see the announcement as a win after years of pushing for stricter oversight of synthetic dyes due to their links to hyperactivity in children and potential carcinogenic properties. The FDA, for example, banned Red No. 3 in cosmetics in 1990, stating that “high doses of the color additive can cause cancer in laboratory animals.” However, some experts argue that the FDA’s delayed action on Red No. 3 highlights larger systemic issues. The agency itself acknowledges that “FD&C Red No. 3 is not as widely used in food and drugs when compared to other certified colors.”

With many other synthetic dyes still in regular use, the ban raises questions about broader regulatory gaps.

According to the Center for Science for the Public Interest (CSPI), last week’s ban is a step in the right direction, but “the FDA and Congress have a long way to go to reform the broken food chemical regulatory system.” The organization asserts that the FDA has failed to effectively monitor the safety of chemicals after they come to market, leading the agency to announce plans for developing an enhanced framework for post-market food chemical safety assessments in 2024. However, that doesn’t address immediate concerns about synthetic dyes and additives currently on American grocery store shelves.

“All Americans deserve foods free from harmful food additives,” said CSPI’s Principal Scientist for Additives and Supplements, Thomas Galligan. “Removing Red 3 and other unsafe, unnecessary food chemicals from our food supply is a critical step for protecting consumers. We hope to see FDA and Congress act soon to reform the broken federal regulatory systems that have allowed unsafe chemicals to enter and stay in our food supply for so long.”

Several synthetic food dyes remain in use today, each with its own applications and controversies. Yellow 5 (Tartrazine), a lemon-yellow azo dye, is among the most widely used and recognized food colorants. Approved in the U.S., EU, Canada, and beyond, it’s found in dairy products, beverages, desserts candies and more. However, it’s also one of the synthetic dyes most often linked to adverse reactions.

Yellow 6 — used in brightly colored treats like AirHeads, Jolly Ranchers and Skittles, as well as snacks like Cheetos and Doritos — adds a vivid orange-yellow hue to products. Similarly, Blue 1 (Brilliant Blue) and Blue 2 (Indigo Carmine) are synthetic dyes that give a greenish-blue and royal blue tint, respectively, to candy, ice cream, beverages and baked goods. Green 3 (Fast Green FCF) is another synthetic dye used in food, drugs and cosmetics, lending a blue-green shade to various products.

Meanwhile, Red 40, one of the most controversial dyes, has recently faced increasing scrutiny. Children are most commonly exposed to Red 40 through cereals, juices, sodas and ice cream.

One major concern among food safety and public health experts is that the FDA relies on outdated studies—some over 70 years old—to establish acceptable daily limits for synthetic dyes. Newer research presents evidence that might prompt reconsideration of those limits. For instance, in 2021, California’s Office of Environmental Health Hazard Assessment (OEHHA) published a report revealing that the seven most widely used food dyes — Blue 1, Blue 2, Green 3, Red 3, Red 40, Yellow 5 and Yellow 6 — can contribute to or exacerbate neurobehavioral problems in some children.

The report highlights evidence linking synthetic dyes to hyperactivity, inattention, and impulsivity, particularly in children with ADHD. Diagnoses of ADHD in U.S. children have risen from 6.1% to 10.2% over the past two decades, and while genetic factors play a role, environmental exposures, including food dyes, may increase susceptibility.

Human "challenge studies" showed that synthetic dyes can trigger neurobehavioral effects in sensitive children. These studies typically involve removing dyes from a child’s diet to establish a baseline, followed by reintroducing controlled doses of dyes to measure behavioral changes. Animal research has also found that dyes like Red 40, Yellow 5 and Yellow 6 affect brain activity, memory, learning and behavior — even at doses below current regulatory thresholds.

Notably, children are exposed to higher levels of synthetic dyes than adults, primarily through brightly colored foods like cereals, juices and candies.

That’s one of the reasons that, in September, California Gov. Gavin Newsom signed a bill into law that will prohibit schools from serving foods containing six artificial food dyes, including Red 40.

“Toxic dyes in food that put kids at higher risk for hyperactivity and other neurobehavioral issues that interfere with learning have no place in our schools,” Brian Ronholm, director of food policy at Consumer Reports, said at the time. “We’ve known for years that synthetic food dyes endanger our health, but the FDA has failed to take action to protect the public.”

Ronholm continued, “California’s landmark new law will help ensure that kids are not exposed to harmful dyes in food at schools that can endanger their health.”

That ban will go into effect on Dec. 31, 2027. Other states, including New York, Maryland, Illinois and South Dakota, have considered bans on Red 40, but none have passed legislation yet.