Is Red Dye 40 and Allura Red the Same Thing?

January 7, 2026 •

3 min read

According to the U.S. Food and Drug Administration (FDA), Allura Red AC is one of nine certified color additives approved for use in foods and beverages. A common question that arises is, "Is Red Dye 40 and Allura Red the same thing?" The short answer is yes; they are indeed the same synthetic food coloring, just identified by different names.

Quick Summary

Yes, Red Dye 40 is the same chemical compound as Allura Red AC, with both being alternative names for the synthetic petroleum-derived food coloring widely used in processed foods, drinks, and cosmetics. They are identified differently depending on the country.

Key Points

Identity: Red Dye 40 is the same chemical compound as Allura Red AC.
Nomenclature: The name used depends on the regional regulatory system; FD&C Red No. 40 or Red 40 in the U.S. and Allura Red AC or E129 in the EU.
Origin: This red food coloring is a synthetic dye derived from petroleum by-products.
Health Concerns: Some studies suggest links between the dye and hyperactivity in sensitive children and other allergic reactions, though regulatory bodies maintain it is safe within limits.
Regulatory Differences: The European Union requires a warning label on products containing this dye, a regulation not currently enforced in the U.S..

What is Red Dye 40?

Red Dye 40, also known as FD&C Red No. 40, is a widely used synthetic food dye in the United States. Derived from petroleum by-products and classified as an azo dye, it provides a red-orange color to many processed foods, drinks, cosmetics, and medications. The FDA permits its use but requires it to be listed on labels as FD&C Red No. 40 or Red 40.

What is Allura Red AC?

Allura Red AC is the internationally recognized name for the same synthetic food coloring. Predominantly used in Europe and other regions, it is often identified by the E-number E129. The "AC" signifies its certification as a food additive. Regulatory bodies outside the U.S., such as the European Food Safety Authority (EFSA), have their own rules regarding its use and labeling.

Why the Different Names?

The variation in names stems from different regional regulatory systems. The U.S. system uses an "FD&C" number, while Europe employs a letter-and-number code (E-number). Thus, it's FD&C Red No. 40 in the U.S. and E129 in Europe, creating potential consumer confusion. Some manufacturers reformulate products for the European market, using natural colorings to avoid mandatory warning labels.

Safety and Health Concerns

Despite being approved by regulatory bodies within specified limits, concerns about the health effects of this dye have been raised. Studies have explored potential links to health issues, leading to differing regulatory approaches globally.

Potential concerns often discussed include:

Hyperactivity: Research has examined the connection between synthetic dyes and hyperactivity, particularly in children with ADHD. Some studies suggest sensitivity in a small percentage of children, where removing the dye might reduce behavioral symptoms.
Allergic Reactions: Though uncommon, allergic responses like hives and itching have been reported in sensitive individuals.
Carcinogenic Potential: Some concerns exist regarding potential links to cancer based on animal studies and the presence of p-Cresidine, a known carcinogen, in the dye. Further human studies are needed to confirm this link.

International Regulations: A Comparison

Regulatory approaches to Red Dye 40/Allura Red AC vary internationally, highlighting ongoing discussions about the safety of artificial food colorings. The table below compares regulations in the United States and the European Union.


Feature	United States (FDA)	European Union (EFSA)
Designation	FD&C Red No. 40 / Red 40	E129 / Allura Red AC
Certification	Mandatory batch-by-batch certification	Certified through EU-wide approval
Labeling	Must be listed by common or FD&C name	Must include warning: “May have an adverse effect on activity and attention in children”
Restrictions	Permitted, with increasing scrutiny at state levels	Permitted, but warning labels encourage use of natural alternatives
Consumption Limit	ADI of 7 mg/kg body weight	ADI of 7 mg/kg body weight (established 1989)

Finding Red Dye 40 on a Product Label

Consumers wishing to avoid this dye should look for its various names on ingredient labels, including FD&C Red No. 40, Red 40, Allura Red AC, Allura Red, CI 16035, and E129 (on European imports). It is common in many food and drink products and may also appear as Red 40 Lake.

Conclusion

Red Dye 40 and Allura Red AC are the same synthetic food coloring, named differently based on regional regulations. Approved for use in many countries, it still faces concerns regarding potential health effects, particularly in sensitive children. Variations in regulations, such as the EU's mandatory warning labels, have led some manufacturers to adopt natural alternatives. Consumers can make informed decisions by recognizing its various names and carefully reading product labels.

Center for Science in the Public Interest: Food Dyes

Resources

For those seeking more information on food additives and natural color alternatives, consider these resources:

Ahimsa Home's Children's Health Blog.
Healthline's article on Red Dye 40.
The European Food Safety Authority (EFSA) website.
PubChem database from the National Institutes of Health.

These resources offer additional details to help you make informed choices.

Frequently Asked Questions

FD&C Red No. 40 is the official name given by the U.S. Food and Drug Administration (FDA) to the same substance, which is also known as Red Dye 40 and Allura Red AC.

While it is not completely banned in the EU, several European countries previously implemented bans before EU-wide regulations standardized its use. The EU now requires a warning label on products containing it, leading many companies to reformulate.

On U.S. labels, it will be listed as Red 40 or FD&C Red No. 40. In other countries, you might see Allura Red AC or the E-number E129. You may also find it as Red 40 Lake.

To avoid Red Dye 40, you must read all ingredient labels carefully and look for its various names. Focus on consuming whole foods that are naturally colorful, like fruits and vegetables, and seek out products specifically marketed as free of artificial dyes.

Yes, natural alternatives exist, such as beet juice for red and beet powder for richer red hues. Other sources include carmine (from cochineal insects), paprika, and various fruit extracts.

According to the FDA and other health organizations, Red Dye 40 is safe for consumption for most people. However, some individuals, especially those with sensitivities or conditions like ADHD, may experience adverse effects, such as hyperactivity or allergic reactions.

Many companies opt for natural alternatives in Europe to avoid the mandatory warning label required by the EU, which states the dye may have an adverse effect on activity and attention in children.