Red 40 is a synthetic food dye made from petroleum. It’s the most widely used artificial color in the U.S. food supply, added to everything from candy and cereal to sports drinks and flavored yogurt to make them look more vivid and appealing. You’ll find it listed on ingredient labels as FD&C Red No. 40, Allura Red AC, or (in Europe) E129.
Red 40 is currently at a turning point. In 2025, the FDA announced plans to phase out all petroleum-based synthetic dyes, including Red 40, from the U.S. food supply by the end of 2026. Here’s what you should know about this ingredient while it’s still on shelves.
How Red 40 Is Made
Red 40 is not extracted from a plant, fruit, or any natural source. It’s manufactured through a chemical process that starts with crude oil. Petroleum is refined into specific chemical building blocks, which are then reacted together to form the bright red pigment.
One concern with this manufacturing process is that it produces trace amounts of benzene, a known carcinogen. Benzene isn’t intentionally added to Red 40, but it can form as a byproduct during production. The dye also breaks down in your digestive tract into several compounds, including aromatic amines. In rat studies, when animals were fed very high concentrations of Red 40 (over 5% of their entire diet), researchers found these breakdown products in both urine and feces, with one aromatic amine called p-cresidine sulfonic acid being the most prominent.
The amounts of these byproducts at normal human consumption levels are extremely small, which is partly why regulators considered Red 40 safe for decades. But the presence of these compounds has fueled ongoing debate about whether long-term, cumulative exposure carries risks that short-term studies miss.
Where You’ll Find It
Red 40 shows up in a surprising range of products, many of which aren’t even red. It’s blended with yellow dyes to create orange hues and combined with blue dyes for purple shades. Common categories include candy, fruit-flavored snacks, cereals, cookies, cake mixes, frosting, gelatin desserts, soft drinks, sports drinks, flavored yogurts, salad dressings, and condiments like ketchup. It’s also used in some medications and supplements, both prescription and over-the-counter, including liquid cold medicines and chewable vitamins.
If you’re trying to avoid it, check ingredient labels for “Red 40,” “FD&C Red No. 40,” or “Allura Red.” In products sold in Europe, it appears as “E129.”
Red 40 and Children’s Behavior
The most persistent concern about Red 40 is whether it contributes to hyperactivity in children, particularly those with ADHD. This question has been studied for decades, and the answer is more nuanced than a simple yes or no.
In 2011, the FDA convened a panel of experts to review all available evidence on synthetic food dyes and children’s behavior. The panel concluded that a causal link had not been established. Several studies published since then, including two large meta-analyses, have found that removing artificial food colors from children’s diets produces a “small to medium” effect on ADHD symptoms. That’s real but modest, and the researchers behind one major 2017 review concluded that eliminating food dyes should not be recommended as a general treatment for ADHD.
What this means in practice: most children who consume Red 40 won’t show noticeable behavioral changes. But a subset of children, particularly those already diagnosed with ADHD or those with a sensitivity to food additives, may be more reactive. Parents who suspect a connection can try removing dyed foods for a few weeks and observing whether behavior shifts.
How Europe Handles It Differently
Red 40 is not banned in Europe, but the European Union has required a specific warning label on any food or drink containing it since July 2010. The mandatory text reads: “Allura Red (E129): may have an adverse effect on activity and attention in children.” Five other synthetic dyes carry the same warning.
This labeling requirement has had a powerful indirect effect. Rather than print a warning that could scare off customers, many European food manufacturers simply reformulated their products with natural colorants. That’s why the same brand of candy or cereal often uses Red 40 in the U.S. version but beet juice or paprika extract in the European version.
The FDA Phase-Out
In 2025, the U.S. Department of Health and Human Services and the FDA announced plans to phase out all petroleum-based synthetic dyes from the American food supply. Red 40 is one of six remaining synthetic dyes being targeted, alongside FD&C Yellow No. 5, Yellow No. 6, Blue No. 1, Blue No. 2, and Green No. 3. The goal is to eliminate them by the end of 2026, working with food manufacturers to transition to alternative colorants.
This is a significant shift. For years, the FDA maintained that Red 40 was safe at typical consumption levels. The phase-out reflects growing pressure from consumer advocacy, the European precedent, and accumulating questions about long-term exposure to petroleum-derived additives.
What Will Replace It
Food companies switching away from Red 40 have several options. The most common natural red colorants include beet juice, carmine (derived from insects), paprika extract, and pigments from fruits like blackberries and red cabbage called anthocyanins.
Historically, natural red colorants have had a reputation for being finicky. They can fade under heat, break down when exposed to light, or lose their color when mixed with vitamin C, which is common in beverages. That’s one reason manufacturers favored synthetic dyes for so long: Red 40 holds its color through baking, freezing, and months on a shelf.
Researchers at Ohio State University have developed a newer class of plant-based pigments called pyranoanthocyanins that maintain their vibrancy under these challenging conditions. These compounds can produce stable red, orange, and yellow hues suitable for fruit juices, sports drinks, gummies, hard candies, and baked goods, all while adding antioxidants rather than petroleum byproducts. As the phase-out accelerates, expect to see more products listing ingredients like “vegetable juice for color” or “fruit and vegetable juice concentrate” where Red 40 once appeared.