Is Red 40 bad for you?
Legal in major markets, but linked to behavior changes in some children.
Also listed as: Allura Red AC, FD&C Red No. 40, E129, INS 129, Red 40 Lake
Is Red 40 in your food?
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What is Red 40?
Red 40 is a synthetic dye made from petroleum-derived chemicals. It is the most widely used food dye in the United States and gives products a bright, stable red color that natural colors struggle to match.
Why manufacturers use it
It is cheap, very stable in heat and light, and gives a consistent color batch after batch, so it shows up in candy, sports drinks, cereals, snacks and baked goods.
Where you'll find it
- Candy and gummies
- Sports and soft drinks
- Breakfast cereals
- Flavored chips
- Frosting
Potential health concerns
- A 2007 UK trial found mixes of synthetic dyes (including Allura Red) increased hyperactive behavior in some children.
- California's 2021 review concluded synthetic dyes can affect behavior in some children.
- Some people report sensitivity reactions such as hives, though these are uncommon.
How it works in the body
Most of the dye passes through the gut and is broken down by gut bacteria. How it might affect behavior is not well understood; leading ideas involve sensitivity in a subset of children rather than a direct toxic effect.
How much is too much
EFSA and JECFA set an acceptable daily intake of 7 mg per kg of body weight. Children who eat a lot of brightly colored snacks and drinks get closest to that level.
What scientific studies indicate
Animal and human studies don't show Red 40 causes cancer at normal intakes. The main concern is behavior: controlled trials show small but real effects in some children, while most children show no change.
Regulatory status by country
United States
Permitted. FDA plans a voluntary phase-out of petroleum dyes; California bans it in school foods from 2028.
European Union
Permitted as E129 with a mandatory warning label about children's activity and attention.
Canada
Permitted (Allura Red).
Australia / NZ
Permitted (code 129).
Why it's rated this color
- Permitted in the US, EU, Canada and Australia/NZ.
- The EU requires a warning that it 'may have an adverse effect on activity and attention in children'.
- Evidence on behavior is mixed but strong enough for regulators to act.
- US regulators announced a plan in 2025 to phase out petroleum-based dyes.
Sources and original research
- Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children — The Lancet (McCann et al.), 2007
- Scientific Opinion on the re-evaluation of Allura Red AC (E 129) — EFSA Journal, 2009
- Potential neurobehavioral effects of synthetic food dyes in children — California OEHHA, 2021
- Color Additives — U.S. Food and Drug Administration
Last reviewed November 2026. Educational information, not medical advice.
Is Red 40 in your food?
Scan your label and get a verdict for every ingredient in seconds.