Artificial Food Dyes In Dog and Cat Food


In 2010, The Center For Science In The Public Interest (CSPI) published a comprehensive food dye report titled, “Food Dyes A Rainbow of Risks.” In the report, the CSPI shed light on the potential health risks associated with the consumption of food dyes. Although this report was directed toward humans, it certainly is not a stretch to extrapolate the findings to the health of our dogs and cats.

According to the CSPI, more than 15 million pounds of artificial food coloring agents are used in the United States annually [1]. In their bid for consumer dollars, manufactures have turned to petroleum based food dyes to artificially color food items. Most people would agree that our pets do not care about the color of their food. Ironically, pet food manufactures insist on using food dyes to convince humans that their products contain wholesome ingredients.

The list of artificial food dyes discussed in this article are classified as “generally recognized as safe” or GRAS by the Food and Drug Administration (FDA). However, as we’ll reveal in this article, the GRAS classification is very misleading.

Risks Associated With Red 3

Red 3 was approved by the United States Department Of Agriculture in 1907 and permanently approved for use in ingested drugs and food products by the FDA in 1969. Since then, Red 3 has been identified as an animal carcinogen by the FDA and banned for use in cosmetics and externally applied drugs [4]. Unfortunately, Red 3 has not been banned for use in food products. Congress passed legislation in 1989 to temporarily restrain the FDA from completely banning Red 3 [5]. Despite the obvious health risk associated with Red 3 consumption, congress faced heavy lobbying by the agricultural industry.

What's particularly alarming is the presence of Red 3 in popular pet food brands, products that are consumed on a daily basis which contain an undisputed animal carcinogen.

Risks Associated With Red 40

The most popular food dye used in consumer goods (and pet food) is Red 40. Studies on Red 40 are highly controversial and deemed by many as inconclusive. However, studies do suggest that Red 40 may accelerate the appearance of tumors in the immune system (in particular, reticuloendothelial system) of mice. Other notable findings are the possibility of hypersensitivity reactions and hyperactivity in children associated with Red 40 consumption [1]. Although the studies do not conclusively confirm any of these findings, the dye is an unnecessary addition and should be avoided, especially in daily consumption.

Risks Associated With Yellow 5

Yellow 5 is another widely used food dye in both human and pet food. According to CSPI, “Yellow 5 may be contaminated with significant levels of carcinogens.” In addition, Yellow 5 is known to cause mild to severe hypersensitivity reactions [1]. In 1986 the Joint Council of Allergy and Immunology urged the FDA to ban Yellow 5 because of the severity and sudden nature of associated reactions. Finally, studies have also linked Yellow 5 with hyperactivity in children. These health concerns are very alarming and should certainly warrant avoiding yellow 5.

Risks Associated With Yellow 6

As with Yellow 5, the CSPI warned in their 2010 report that “Yellow 6 may be contaminated with significant levels of recognized carcinogens.” Studies have suggested that Yellow 6 can be linked to tumors (adrenal medullary adenomas) but the FDA claimed that the tumors were not significant for various reasons. Finally, as with Yellow 5, Yellow 6 can also cause hypersensitivity reactions and hyperactivity in children. Thus, Yellow 6 also poses serious health concerns and should be avoided [1].

Risks Associated With Blue 1

Blue 1 was approved by the FDA in 1969 for general use in food and ingested drugs. Industry sponsored studies have not shown any clinical signs attributed to Blue 1, however these studies have been short in duration. As noted by the CSPI, adverse effects can occur years after exposure.

Studies outside those sponsored by industry have raised alarming concerns of possible neurotoxicity and an increased chance of kidney tumors.

Risks Associated With Blue 2

Blue 2 was approved in 1983 by the FDA for use in foods and ingested drugs. Studies have identified a statistically significant occurrence of tumors in male rats associated with Blue 2 [3]. However, the FDA has contended that these findings are questionable for various reasons outlined in the CSPI report. The Public Citizen Health Research Group (HRG) has objected the FDA’s decision claiming that the studies suggest Blue 2 is a carcinogen [1]. Whether the FDA or its challengers are correct, Blue 2 is an unnecessary addition in pet food which should be avoided.

Final Thoughts

Pet owners should avoid all artificial food dyes for two simple reasons.

  1. They carry proven/potential health risks.
  2. They do not provide any nutritional benefit.

Long term exposure to food dyes can have serious consequences. Unlike candy and soft drinks which may be consumed occasionally, our pets are exposed to the same products daily. Therefore the risk associated with each potentially dangerous ingredient is significantly higher.

References & Notes

  1. Center For Research In The Public Interest, "Food Dyes A Rainbow of Risks", 2010.

  2. Hansen, W. H., O. G. Fitzhugh, et al. (1964). “Chronic toxicity of two food colors, Brilliant Blue FCF and Indigotine.” Toxicology and Applied Pharmacology 8: 29-36.

  3. Borzelleca, J. F., E. I. Goldenthal, et al. (1986). “Multigeneration study of FD&C Blue No. 2 in rats.” Food and Chemical Toxicology 24(2): 159-63.

  4. FDA (1990). Termination of provisional listings of color additives

  5. Washington Post (July 19, 1989). “House agrees to let FDA keep cherry dye on market.”