Red 40
Allura Red AC · FD&C Red No. 40 · E129
A petroleum-derived synthetic dye used to color thousands of American foods — and the most commonly used food coloring in the United States.
Why we flag it
Red 40 has been linked to behavioral effects in children, including hyperactivity and attention difficulties. A 2021 California state assessment of 25 studies concluded that synthetic food dyes — Red 40 in particular — can cause or worsen neurobehavioral problems in some kids, even at exposure levels considered safe by the FDA.
The dye also contains trace amounts of benzidine, a known human carcinogen, formed during manufacturing. The FDA permits these residues below a daily intake threshold; the European Food Safety Authority has set much stricter limits, and several European countries require a warning label on foods containing Red 40.
Where you'll find it
Anywhere bright red, pink, purple, or orange shows up in processed food. Common sources include:
- Candy and gummies (Skittles, Starburst, gummy worms)
- Sports drinks and soda (Gatorade red flavors, fruit sodas)
- Breakfast cereals marketed to kids (Lucky Charms, fruit-flavored cereals)
- Boxed mac & cheese, packaged baked goods, frostings, jellies
- Flavored yogurts, ice cream, frozen popsicles
- Some over-the-counter medications and vitamins
What to look for instead
Many brands now use plant-based colorants that achieve similar shades without the synthetic dye:
- Beet juice or beet powder — deep pink to red
- Carmine (from cochineal insects) — true red, though not vegan
- Lycopene (from tomatoes) — red to orange
- Paprika extract — orange-red
- Hibiscus, elderberry, purple carrot — deep reds and purples
On the label, look for the words "colored with fruit and vegetable juices," "no artificial colors," or specific natural colorants listed by name.