What is E127?

Complete guide to understanding E127 (erythrosine) in your food and products

The Quick Answer

E127 is a synthetic red dye used to add color to foods and products.

It’s used to give candies, drinks, and certain medications a bright pink-to-red color.

As of January 2025, the U.S. FDA has banned it from food and ingested drugs, though it remains permitted in limited quantities in Europe.

What Exactly Is It?

E127 (erythrosine) is a synthetic organic dye created in a laboratory by chemists, not found in nature.

It’s made from resorcinol and phthalic anhydride, which are processed into a base compound called fluorescein. This fluorescein is then treated with iodine to create the bright red erythrosine dye.

The chemical formula is C₂₀H₆I₄Na₂O₅ — meaning it contains four iodine atoms that give it its distinctive pink-to-red color.

In technical terms, it’s classified as a xanthene dye, belonging to the fluorescein family of colorants.

The name comes from the Greek word “erythros,” meaning red.

Where You’ll Find It

E127 appears in many products you’ve likely consumed:

If you ate processed foods or candies in the past decade, you’ve almost certainly consumed E127 multiple times.

Why Do Food Companies Use It?

E127 does one main job: it makes food look more appealing by adding a bright pink or red color.

Consumers associate bright red colors with freshness, ripeness, and quality — especially for products like cherries, candy, and baked goods. Without E127, these products would look pale, dull, or unappealing on store shelves.

E127 is also stable during manufacturing and storage, meaning the color doesn’t fade or change over time like natural dyes might. It’s also relatively inexpensive compared to natural color alternatives.

So food companies add it for purely practical, commercial reasons: to make food sell better.

Is It Safe?

The safety of E127 is complicated and debated among regulatory agencies.

The Official Position

For decades, European and U.S. regulatory bodies deemed E127 safe at approved levels. The European Food Safety Authority (EFSA) set an acceptable daily intake (ADI) of 0-0.1 mg per kilogram of body weight per day.

Most people consume E127 in much smaller amounts than these limits allow:

Why the FDA Ban in 2025?

On January 15, 2025, the U.S. FDA banned E127 from food and ingested drugs — but not for the reasons you might think.

The ban was mandatory under the Delaney Clause, a 1958 law that prohibits ANY food additive shown to cause cancer in laboratory animals, regardless of the dose or likelihood of human risk.

Research dating back 30+ years showed that E127 caused thyroid tumors in male rats at extremely high doses. This triggered the Delaney Clause automatically.

However, the FDA’s own statement is important:

Animal Studies vs. Human Reality

Potential Health Concerns (Under Research)

Hyperactivity and Behavioral Effects

Some studies suggest E127 may increase hyperactivity or restlessness in sensitive children, though the effect is small.

Important context:

• Not all children react; genetic polymorphisms in genes controlling histamine degradation may increase sensitivity
• The effect size is small (accounting for only a fraction of overall behavioral problems)
• Other factors — genetics, diet, environment — play much larger roles
• This concern led the EU to restrict E127 significantly in 1994

Thyroid Hormone Disruption

At very high doses, E127 may affect thyroid hormone metabolism and increase TSH (thyroid-stimulating hormone) levels.

However: These effects are dose-dependent and were observed primarily in high-dose animal studies. Effects are reversible at lower doses, and no thyroid problems have been documented in the general human population from E127 consumption.

Other Potential Effects (Limited Evidence)

• May trigger bronchial asthma in susceptible individuals
• May increase photosensitivity (skin reactions to sunlight)
• Some animal studies suggest links to inflammation, though human evidence is lacking

Natural vs. Synthetic Version

E127 is 100% synthetic. There is no natural version of erythrosine found in plants or animals.

This is different from some food dyes. For example, “natural red” dyes like anthocyanins (E163) come from berries, while carmine (E120) comes from cochineal insects. But erythrosine must be manufactured in a laboratory.

Natural Alternatives to E127

Want to avoid E127? Food companies use several natural alternatives that achieve similar red coloring:

These alternatives work similarly to E127 but cost more, which is why manufacturers still used E127 despite regulatory pressures — until the 2025 U.S. ban forced reformulation.

The Bottom Line

E127 (erythrosine) is a synthetic red dye used to make processed foods more visually appealing.

For most people consuming normal amounts, regulatory agencies concluded it posed minimal health risk — though the EU restricted it significantly in 1994 due to hyperactivity concerns, and the U.S. banned it in 2025 due to animal carcinogenicity findings.

The evidence suggests:

• Thyroid cancer risk in humans: No documented cases despite decades of use; theoretical risk is ~1 in 100,000
• Behavioral effects: Small effect in sensitive children; not all children affected
• Acute toxicity: Very low; you’d need to consume enormous amounts in one sitting to cause immediate harm

What you should do:

• Read labels if you prefer to avoid artificial dyes
• In the U.S., E127/Red No. 3 products are being reformulated and phased out by January 2027-2028
• In Europe, E127 remains permitted in limited applications (cocktail cherries, candies, toothpaste)
• If you have concerns about artificial dyes generally, seek products labeled “dye-free” or using natural colorants
• For children sensitive to artificial dyes, avoiding E127 and other synthetic dyes may help reduce behavioral symptoms