From vibrantly frosted cupcakes to fruity cereal and rainbow bagels, synthetic dyes are often found in a variety of foods. The U.S. Food and Drug Administration (FDA) allows the use of seven synthetic dyes to impart color on food, but many are being phased out amid growing public concern about whether synthetic food dyes (also called artificial food colorings) are linked to various health concerns, including cancer.
Can red dye cause cancer?
In 2022, a color additive petition led the FDA to prioritize banning FD&C Red 3 (also called Red No. 3) — often found in sweets, cough syrup, and gummy vitamins — because studies from the 1990s in animal models have shown that it may cause cancer. While human studies have yet to show the same result, the FDA is acting out of precaution because of the Delaney Clause, a regulation in the Federal Food, Drug, and Cosmetic Act of 1938 that bans the use of carcinogenic additives in foods consumed by humans and animals.
Today, the FDA is collaborating with manufacturers to phase out Red 3 and six other petroleum-derived artificial food colorings from America’s food supply by 2028. Those synthetic food dyes include:
- FD&C Red 40
- FD&C Green 1
- FD&C Yellow 5
- FD&C Yellow 6
- FD&C Blue 1
- FD&C Blue 2
What about other color dyes?
In the United States, color additives undergo a multistep process before the FDA approves them for use in food and cosmetics. Researchers must present evidence that the recommended synthetic food dye is safe and in which amounts, determine which foods and cosmetics in which it can be used, and show how it should be declared on food labels. Artificial food colorings can be certified — such as the seven currently approved by the FDA, but are being phased out — or exempt from certification. The latter applies to dyes and pigments from natural sources (animal, vegetable, or mineral).
Color additives are usually limited to the amount necessary to achieve the desired effect. Federal authorities may prohibit use of a particular color additive or conduct further studies if:
- Consumption levels have changed significantly — that is, more people are eating, drinking, or using a particular product that contains a synthetic food dye
- Evidence suggests that the product in use may be unsafe
Which foods have artificial dye in them?
The most common foods to contain synthetic food dyes are ultra-processed foods – namely fast food, convenience foods, sweets, and baked goods. More research is needed, however, on whether increased cancer risk is due to exposure to artificial food colorings alone or to overall diet quality.
In a diet with high amounts of ultra-processed foods, there is greater exposure to synthetic food dyes, added sugar, preservatives, and flavor enhancers.
“Ideally, researchers studying the health effects of ingredients in ultra-processed foods control for additional factors, such as weight or overall diet quality, to try to determine if a health outcome is related to synthetic food dyes versus overall diet and lifestyle influences,” explains Hillary Wright, MEd, RD, LDN, a senior oncology dietitian/nutritionist at Dana-Farber. “That said, ultra-processed foods contain many different additives and other highly processed ingredients. It can be difficult to isolate what exactly may be causing a health issue. We do know, however, that ultra-processed foods are replacing many whole foods in our diets that we know are associated with better health – including lower cancer risk – such as fruits, vegetables, whole grains, nuts, seeds, and beans.”
Lowering your risk
Over time, adding more nutrient-dense foods to a person’s diet can help decrease their intake of ultra-processed foods. “This is a more positive approach than restricting or removing certain foods or food groups,” says Wright. “We want to help patients build healthy, sustainable habits from where they are so they can feel empowered to move toward where they want to be.”
To lower the risk of cancer, guidance from the American Institute of Cancer Research recommends to:
- Add more whole, unprocessed or minimally processed foods to meals and snacks whenever possible
- Avoid highly processed meats, like bacon, hot dogs, canned meat, or deli meat
- Limit intake of red meat, ultra-processed foods, and alcohol
A person’s ability to add whole, unprocessed or minimally processed foods, however, may be determined by external factors. “There are many people who have limited access to whole foods, whether it’s because of where they live, financial constraints, or gaps in knowledge or skills related to food selection and preparation,” says Wright. “That’s why it’s important to start where the patient is and help them build a solid nutritional foundation that works for their needs and circumstances.”
Balance is best
Cancer prevention and overall health are greatly influenced by lifestyle habits. Wright and her team give particular focus to overall diet quality and ensuring that dietary and physical activity recommendations improve a patient’s quality of life — not detract from it.
“Food is one of life’s greatest pleasures,” she adds. “Food carries a lot of cultural and societal value, and we want to honor and embrace that. When we look at the quality of a patient’s diet, we ask what they eat most of the time versus what they eat on occasion.”
When working with patients, Wright and her team also pair evidence-based nutrition recommendations with physical activity. “In today’s sedentary world, we often miss out on movement that provides chemistry changes within the body to protect against disease,” she notes. “Our bodies are made to move, but it can be challenging to do that. Any movement helps, and starting the healthy habit of engaging in physical activity can provide enormous benefits for overall physical and mental well-being.”
The bottom line
More research is needed on whether increased cancer risk is due to exposure to synthetic food dyes or to diet quality. Evidence does show, however, that physical activity in partnership with eating a balanced diet with a variety of whole, unprocessed or minimally processed foods can lower cancer risk and contribute to better overall health.
Learn more about Dana-Farber’s Nutrition Services here or by talking with your care team.