What is FD&C Red #3?
A cherry-pink colored synthetic dye used in food and ingested drugs both the US and Europe.
It is banned from use in cosmetics and external drugs (1).
It is the second least-commonly used dye, after FD&C Green #3 (Red #40 is usually used instead of Red #3).
FD&C Red #3 contains iodine, unlike most other synthetic food dyes.
Other names for FD&C Red #3:
- E127 (Europe)
Processed foods that may contain FD&C Red #3:
- Canned fruit
- Maraschino cherries
- Meal replacement shakes
- Sausage casings
Products that may contain FD&C Red #3:
How is FD&C Red #3 absorbed and metabolized?
Less than 1% of FD&C Red #3 is absorbed in the intestines, and 80 to 100% is recovered in the feces (2).
Is there a maximum amount of FD&C Red #3 allowed per day?
The acceptable daily intake (ADI) for Red #3 is 0.1 mg/kg body weight/day (3).
Can people have adverse reactions to FD&C Red #3?
Linked to increases in fidgetiness, irritability, and sleep problems in some children, but studies have been widely variable. This may be because some kids have hypersensitivity reactions (aka food sensitivities) to these dyes. (5, 6, 7, 8).
In rats, it has been shown to induce hyperactivity at high doses, potentially by affecting serotonin metabolism. But lower doses didn’t produce these effects (6).
Can cause increased protein-bound iodide levels (PBI) in people taking medications with capsules that were dyed pink with FD&C Red #3, or when consuming more than 20mg per day (9, 10, 11).
Rat studies have found that ~1/4 to 1/3 of the iodide in the dye is metabolized into free iodide. High doses of FD&C Red #3 have been shown to disrupt thyroid hormone production in rats (increased T3 & T4, & an 80% greater release of TSH from the pituitary when stimulated by thyrotropin-releasing hormone), but it is unclear whether the effects are caused by increased iodine levels or the dye directly (12, 13).
Humans consuming 200 mg/day have also shown increased TSH levels (11).
High doses (up to 136 mg per kg body weight) have been shown to reduce sperm count by 50% in 21 days in rats (14).
Rats fed food high doses (4-5% in food) of FD&C Red #3 for several years had growth retardation, reduced spleen size, kidney tubules that were stained pink, enlarged cecum, enlarged thyroid, and increased rate of thyroid tumors, but no ill effects were found with the same dosages fed to dogs (15, 16, 17).
Much lower dosages (<0.5%) showed no developmental effects in rats but did impact their exploratory behavior (18).
Has been found to cause DNA damage when cells are incubated with the dye… but that’s not really representative of what happens in the body after you eat it (19).
Has been shown to be harmful to human lymphocytes at doses of 2 mM, and also inhibit proper immune system functioning, but these doses would not occur in the human body if you stick to the ADI (20, 21).
Has been shown to shut down mitochondrial function in large doses (22).