Blue 1 in Dog Food

Blue 1 in dog food is used as an artificial food coloring to make your dog’s food look nicer. This food dye is considered quite harmless overall, but it has no benefits for your dog’s diet.

What is Blue 1?

Blue 1 is a reddish-purple powder with a metallic luster. It’s made from benzene, which is ultimately derived from petroleum.

Due to its complex chemical structure, it is classified as a triphenylmethane dye (like green 3). These are intensely colored synthetic organic compounds.

Blue 1 a complex molecule with some trivial names like Brilliant Blue FCF, E 133, CI Food Blue 2, and FD&C Blue No 1.

There’s only one purpose for Blue 1 in dog food:

It’s an artificial bright blue color additive.

A manufacturer that uses Blue 1 in dog food wants to make a product look more attractive or varied than it actually is.

For example, combined with other dyes it can make kibble browner to resemble cooked meat[5].

But aside from making its kibble pretty, it doesn’t add any benefits at all for your dog.

Blue 1 in dog food kibble

Is Blue 1 in Dog Food Bad?

Blue 1 is permitted as a food dye in the European Union and the United States of America. Brilliant Blue was one of the earliest FDA-approved color additives!

It’s not only used in pet food but also in many blue-colored products like cotton candy, ice creams, drinks, soaps, shampoos, mouthwash, and other hygiene and cosmetic products.

Blue 1 in dog food food additive

In the US, Blue1 is a restricted color additive and always has to be mentioned by name on the dog food label. Meaning, it can never be hidden behind umbrella terms like “added color“.

Although it’s water-soluble, only about 5% of Blue 1 is absorbed by the body and then excreted via bile or urine. In heathy dogs, the majority of this substance gets eliminated without ever leaving the gastrointestinal tract[3].

Many studies confirmed that Blue 1 is non-toxic and neither carcinogenic nor mutagenic. As a food additive, it’s also not a common trigger for allergies[2].

But there is growing evidence of some adverse reactions to this class of synthetic dyes. In humans, they can inhibit mitochondrial respiration or cause hypersensitivity or pseudo-allergic reactions[1,3,7].

Based on growing evidence, the original acceptable daily intake (ADI) for Blue 1 for humans has been reduced over the years from 12.5 mg/kg body weight per day (1969) to 6 mg/kg (2010)[2,4]

In 2013, the European Food Safety Authority re-evaluated the safety and efficacy of Brilliant Blue FCF as an additive in pet food.

In conclusion, they found a concentration of up to 334 mg/kg of Blue 1 in dog food to be safe for dogs and recommended a maximum content of 300 mg/kg for complete food[5].

But there is no legal maximum content and US manufacturers can use Blue 1 in any amount “consistent with good manufacturing practice[6] (oftentimes at parts per million).

So… should you avoid Blue 1 in dog food?

Probably, yes. Especially if you prefer natural dog food.

But to be fair, there is little reason to worry when your dog eats kibble or treats with this artificial color now and then. For most dogs, Blue 1 is harmless and unlikely to ever cause any problems.

But even the slightest chance that it could seems too risky much to make it an acceptable ingredient in everyday dog food. Remember, Blue 1 offers no benefits whatsoever!

Luckily, it has to be labeled clearly. This makes it easy to spot in the ingredient list and easy to avoid when shopping for dog food.

Further Reading

[1] Kobylewski & Jacobson. Toxicology of food dyes. International Journal of Occupational and Environmental Health. 2012. https://doi.org/10.1179/1077352512Z.00000000034

[2] World Health Organization & Joint FAO/WHO Expert Committee on Food Additives‎. Evaluation of certain food additives: 84th report of the Joint FAO/WHO Expert Committee on Food Additives. WHO Technical Report Series. 2017. https://apps.who.int/iris/handle/10665/259483

[3] Lucová et al. Absorption of triphenylmethane dyes Brilliant Blue and Patent Blue through intact skin, shaven skin and lingual mucosa from daily life products. Food and Chemical Toxicology. 2013. https://doi.org/10.1016/j.fct.2012.10.027

[4] EFSA Panel on Food Additives and Nutrient Sources added to Food. Scientific opinion on the re-evaluation of Brilliant Blue FCF (E 133) as a food additive. EFSA Journal. 2010. https://doi.org/10.2903/j.efsa.2010.1853

[5] Panel on Additives and Products or Substances used in Animal Feed (FEEDAP). Scientific opinion on the safety and efficacy of Brilliant Blue FCF (E133) as a feed additive for cats and dogs. EFSA Journal. 2013. https://doi.org/10.2903/j.efsa.2013.3288

[6] 21 CFR § 74.101 FD&C Blue No. 1

[7] FDA Public Health Advisory. Reports of Blue Discoloration and Death in Patients Receiving Enteral Feedings Tinted With The Dye, FD&C Blue No. 1. 2003.