In 1990, the Food and Drug Administration banned the use of red dye No. 3 — also known as erythrosine or FD&C Red No. 3 — in cosmetics and externally applied drugs, based on its analysis of unpublished animal research suggesting a link to thyroid cancer.
But the agency still allows its use in thousands of foods, dietary supplements and ingested drugs.
There is no evidence that ingesting red dye No. 3 or any other artificial food colors causes cancer in humans. Scientists, however, tend to use results of animal studies to understand possible effects in people.
“The FDA says it isn’t safe enough to put it on our cheeks, but it’s okay to put it in our mouths?” said Lisa Lefferts, a scientist and consultant to Center for Science in the Public Interest (CSPI), which filed a petition with the FDA seeking the dye’s removal from products consumers eat and drink. “That’s crazy.”
Lefferts said that the industry mostly uses these colorings “to make junk food more attractive, especially to kids.”
FDA officials declined a request to discuss red No. 3, saying it does not comment on pending petitions, referring to the CSPI filing.
The International Association of Color Manufacturers, which represents the dye industry, defended dye safety, specifically red dye No. 3, pointing to its long and widespread use.
Toxicologist Linda Birnbaum, also a microbiologist and former director of the National Institute of Environmental Health Sciences, part of the National Institutes of Health, and the National Toxicology Program, said it’s still a good idea to avoid additives because children are still developing, making them more susceptible than adults.
“Children are not little adults,” Birnbaum said. “Often because their bodies are rapidly growing and changing, they are more at risk from chemical exposure than adults would be.”
The dye — which must appear in a product’s list of ingredients — is in, among other things, baking chips and sprinkles, ice cream cones, frostings and icings, frozen dairy dessert, sherbet, soft candy and gummies, meal replacement drinks and bars, cookies, toaster pastries, ice pops and frozen fruit bars, according to an FDA exposure assessment.
It’s also found in many non-red-appearing items. “Consumers may be surprised to learn that the dye is also used in foods that don’t look red,” Benesh said. “Just avoiding red foods won’t necessarily protect you from exposure.”
Studies on the safety and use of red dyes
The safety of artificial colors added to foods has long been the subject of scientific debate. The FDA has prohibited a number of them, including reds 1, 2 and 4, and greens 1 and 2. In December, a Canadian study on mice found that another commonly used red — Allura Red AC, also known as FD&C Red 40 and Food Red 17 — could trigger inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease.
Other studies have connected several artificial dyes, including red dye No. 3, to hyperactivity and other behavioral problems in children. A report released in 2021 by the California Office of Environmental Health Hazard Assessment concluded that some children who consume food dyes exhibit these health effects, although sensitivity to them varies among children. Based on these findings, in December, CSPI petitioned California to add warning labels to foods containing artificial dyes.
The International Association of Color Manufacturers referenced a 14-day human study that found no ill effects on thyroid function among 30 men, divided into three groups with each taking a different daily dose of red dye No. 3, including 20, 60 and 200 milligrams. The study — because it only lasted two weeks — did not address long-term exposure and the risk of cancer.
Regarding the cancer study in rats, however, Sarah Codrea, the organization’s executive director, said that “effects in experimental animals were observed at doses at least 60-fold higher than the levels of no effect observed in the human study.”
Animal research typically involves administering high doses in small numbers of animals to compensate for their shorter life spans, in this case, about two years for rodents. Also, doses in animals must reach body levels equivalent to those in larger humans, Birnbaum said. “The important thing is how much is in your body,” she said. “We have a range in the human population of how much people are exposed to, and rodent studies overlap the high end of general population exposure.”
Opposition to the use of red dye in food
Those who support the CSPI petition — nearly two dozen groups and scientists — often cite the Delaney clause, which Congress passed in 1958 as part of the federal Food, Drug, and Cosmetic Act, as a basis for banning the chemical. The law explicitly forbids the addition of anything to the food supply that causes cancer in humans or animals.
“Delaney is a slam dunk. If it causes cancer in humans and animals, you can’t put it in food,” said Tom Neltner, senior director of safer chemicals for the Environmental Defense Fund. “The FDA seems to feel that you have to prove it is unsafe and harming people before it can be removed, but that’s not what the law says.”
Brian Ronholm, director of food policy for Consumer Reports — which also signed on to the petition — agreed. “It’s frustrating and completely illogical,” he said.
In 1960, the FDA gave “provisional” — that is, temporary — permission to add the dye to both cosmetics and foods. In 1969, before studies suggested it was carcinogenic, the FDA allowed for its “permanent” use in foods, but kept its provisional status in cosmetics, pending the outcome of skin exposure studies.
After making the cancer connection in animals, the agency banned its use in cosmetics, where it had been allowed temporarily, and later declared its intention to remove it from food. But it never did because a permanent designation is tantamount to approval; and once approved, it’s hard to get rid of it. “It’s easier to deny a petition to permanently list an additive — as the FDA did with cosmetics — than it is to revoke an approval,” Lefferts said.
Neltner pointed out that Congress in March appropriated $7 million in new money for the FDA for “emerging chemical and toxicology issues” in fiscal year 2022. Then, in fiscal year 2023 appropriations enacted in December, lawmakers added another $1 million — for a total of $8 million — for that purpose.
Neltner said he hopes this money will spur the agency to finally move against red dye No. 3 and other substances. “The FDA needs to identify what needs to be fixed when there is evidence of a problem,” he said.
Alternatives to red dye No. 3
Meanwhile, critics suggested that the industry consider using safer color alternatives such as fruits and vegetables, even if they cost more.
“There’s no reason for us to have synthetic dyes in our food,” Lefferts said. “It would be much better to use real ingredients in that strawberry shake — like strawberries.”
Consumers concerned about food dye safety can avoid them by reading labels when they shop. The FDA requires that specific food dyes be listed among the product’s ingredients.
If you want to avoid them in home cooking and baking, there are many natural choices that can add color, including extracts from fruits (strain out the seeds) such as raspberries, blackberries and strawberries. Also, try using beet powder or concentrated fruit or vegetable juices.
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