Artificial Food Coloring (Synthetic Food Dyes)

Additive

Synthetic food dyes add bright, even color to foods and drinks. This review covers Blue 1, Blue 2, Green 3, Red 40, Yellow 5 and Yellow 6. They differ chemically, and the words “artificial color” alone do not identify them.

Also known as

synthetic food dyes · synthetic food colors · synthetic food colours · FD&C certified colors · Blue 1 · Blue 2 · Green 3 · Red 40 · Yellow 5 · Yellow 6

Why PRūF tracks it

Some synthetic dye challenges have affected activity or attention in children, with variable responses and negative trials; newer animal findings for particular dyes warrant follow-up but do not establish equivalent effects in people.

This guide covers a group of ingredients. The specific ingredient, preparation and amount matter when interpreting the research.

Read the research

Synthetic dyes are a group, and findings for one dye do not establish equal effects from all others. Controlled challenge studies support changes in activity or attention in some children, but results vary across doses, mixtures, observers and individuals. A review of 25 challenge studies found a behavioral signal in some trials; a later Hong Kong trial found no significant adverse effect. These studies do not show that dyes cause ADHD or that every child reacts.

Laboratory studies also raise questions about particular dyes: Red 40 affected DNA and intestinal inflammation in mice, while other guideline tests were negative. A 2026 study found that Sunset Yellow worsened experimentally induced egg-protein allergy in mice given 40 milligrams per kilogram of body weight; this is not evidence that ordinary food exposure causes human allergy. West Virginia restricts the six named dyes in school nutrition meals, and California has enacted school restrictions beginning December 31, 2027, with specified exceptions. Generic “artificial color” wording can include other pigments, so the named ingredient matters.

Research reviewed on September 5, 2026 · 12 sources