Reactions to food dyes are not IgE (true allergic ) reactions, and they are often classified as food intolerances rather than food allergies. There are IgG tests that can determine sensitivity to food dyes.
There is often confusion regarding food colorings. "Dyes" are water soluble, "lakes" are oil soluble, and both are made from Food and Drug Administration approved colorants.
Although the FDA considers food colorants to be safe, they do allow that certain individuals may have sensitivities, and therefore mandate that artificial colors be listed on labels. The approved chemical colors are:
- FD&C Blue #1: Erioglaucine
- FD&C Blue #2: Indigotine
- FD&C Green #3: Fast Green
- FD&C Red #3: Erythrosin B
- FD&C Red #40: Allura Red
- FD&C Yellow #5: Tartrazine
- FD&C Yellow #6: Sunset Yellow
- Orange B (allowed only in hotdog and sausage casings, and only up to 150 ppm of the finished food weight)
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