What Are Food Dyes? The Complete Guide to Artificial Color Additives

Key Takeaways

What Are Food Dyes?

Food dyes — also called food colorings, color additives, or artificial dyes — are substances added to food and beverages to change or enhance their color. They're used to make products look more visually appealing, compensate for color lost during processing, and create a consistent appearance across batches.

There are two main categories:

When people talk about "food dyes" in the context of health concerns, they're almost always referring to synthetic, petroleum-derived dyes.

Where Do Artificial Food Dyes Come From?

Most artificial food dyes are synthesized from petroleum byproducts. This surprises many people.

The manufacturing process involves chemically reacting aromatic hydrocarbons (compounds derived from petroleum) to produce stable, intensely colored molecules called azo dyes (for reds, oranges, and yellows) or triarylmethane dyes (for blues and greens).

The resulting dyes are tested for purity, then certified by the FDA before being sold to food manufacturers.

The Most Common Food Dyes in the U.S.

The FDA currently certifies seven synthetic dyes for use in food:

Of these, Red 40, Yellow 5, and Yellow 6 account for the vast majority of food dye use in the United States.

Red 40: The Most Widely Used Food Dye

Red 40 (also called Allura Red AC) is the single most consumed food dye in the United States. It's used in thousands of products — from Doritos and Skittles to certain brands of strawberry yogurt and ketchup.

What the science says about Red 40

Despite its widespread use, Red 40 has accumulated a meaningful body of research raising questions about its safety, particularly for children.

Hyperactivity and behavioral effects: The most extensively studied concern is whether Red 40 contributes to hyperactivity in children. The study found that a mixture of artificial food dyes (including Red 40) plus sodium benzoate significantly increased hyperactivity in children aged 3 and 8-9 years. The effect was observed in children both with and without ADHD diagnoses.

What the EU did: In response to this study, the European Food Safety Authority (EFSA) required manufacturers using the six dyes studied (nicknamed the "Southampton Six") to add warning labels reading: "May have an adverse effect on activity and attention in children." The UK's Food Standards Agency went further, recommending voluntary removal. The United States took no such action — a regulatory gap that consumer advocates have criticized for years.

Allergy and sensitivity reactions: Red 40 contains trace amounts of benzidine, a known human carcinogen and a chemical linked to allergic reactions. Some individuals — particularly those sensitive to aspirin or with existing allergies — report reactions including hives, itching, and respiratory symptoms.

Red 3: The Dye That Was Finally Banned (Partly)

Red 3 (Erythrosine) has one of the most complicated regulatory histories of any food additive in the United States.

A ban that took 35 years

In 1990, the FDA banned Red 3 from cosmetics and externally applied drugs after studies showed it caused thyroid tumors in male rats at high doses. The FDA was legally required under the Delaney Clause — a provision of the Federal Food, Drug, and Cosmetic Act — to ban any additive shown to cause cancer in animals or humans, regardless of the dose.

But here's the absurdity: the FDA simultaneously banned Red 3 from lipstick and cosmetics while continuing to allow it in food and ingested drugs. The dye remained legal in maraschino cherries, certain candies, and medications for over three more decades.

It wasn't until January 2025 that the FDA finally banned Red 3 from food and ingested drugs — a full 35 years after the cosmetics ban. The FDA gave manufacturers until January 2027 (for food) and January 2028 (for drugs) to reformulate.

Why Are Food Dyes Still Used?

If there are questions about the safety of artificial food dyes, why are they still in so many products? The answer comes down to a few factors:

The International Regulatory Gap

One of the most important things to understand about food dyes is how differently they're treated around the world, and what that tells us.

The European Union requires warning labels on the "Southampton Six" dyes (including Red 40, Yellow 5, and Yellow 6) in any food sold to consumers.

In response to this labeling requirement, many major food companies — including Kraft, McDonald's, and Pepsi — quietly reformulated their European products to remove artificial dyes, replacing them with natural alternatives. These same companies continue to use artificial dyes in their U.S. products.

If you buy Fanta in the UK, it's colored with pumpkin and carrot extract. In the United States, it's colored with Red 40 and Yellow 6.

The same product. Two formulas. One country's children get artificial dyes. The other's don't.

State-Level Action in the U.S.

In the absence of federal action, several U.S. states have moved to restrict or ban artificial food dyes, particularly in school foods.

These state-level movements reflect growing public concern and regulatory frustration — and signal that the federal landscape may be changing.

How to Identify Food Dyes on Ingredient Labels

You can use the Trash Panda App to easily spot and avoid any added food dyes in your food. With a quick barcode scan you will be able to see if any food dyes are listed in the ingredients.

How Trash Panda Helps You Avoid Food Dyes

Knowing which food dyes to avoid is one thing. Actually avoiding them while grocery shopping is another — especially when you're reading ingredient labels on 30 different products in a busy store.

Trash Panda is a free app that lets you scan any product barcode and instantly see a breakdown of its ingredients, including any artificial food dyes. The app flags certified color additives, explains what the research says about each one, and shows you cleaner alternatives.

Whether you're trying to cut Red 40 from your family's diet, looking for products without the Southampton Six, or just trying to understand what's actually in your food, Trash Panda can help you shop with confidence.

The Bottom Line on Food Dyes

Food dyes are a case study in how the U.S. food safety system works — and where it falls short.

The evidence against several common artificial dyes, particularly Red 40 and the broader Southampton Six, is strong enough that the European Union requires warning labels and many major food companies have already reformulated for European markets. The U.S. regulatory process has been slower, though state-level pressure and the long-overdue Red 3 ban signal that the tide may be turning.

For consumers who want to minimize artificial dye exposure — especially for children — the practical approach is to read ingredient labels carefully, understand which products are most likely to contain dyes (candy, cereals, beverages, snack foods), and use tools like Trash Panda to scan products quickly to spot hidden dyes.

Trash Panda is an ingredient transparency app that helps consumers understand what's in their food. For more information on specific food dyes, read our deep dives on Red 3 and Red 40.