'No nutritional benefit': Are there health risks associated with red dye?

Food dyes can be found in several foods, including candies and even salted fish, but there's one hue that may be harmful to your health -- the colour red.

While Health Canada considers many red dyes safe, it's not the same in every country because of connections to cancer, and hyperactivity in children.

"As far as I know, these dyes are actually not beneficial. These dyes have no nutritional benefit,” said Waliul Khan, a professor in the department of pathology and molecular medicine at McMaster University.

Khan has studied red dye 40, or allura red, which is found in candies, cereals, some dairy products, and soft drinks.

His lab found that in animals the dye affected digestion.

"Chronic exposure to the animals actually increases the inflammation in the gut,” he said.

In the United States, another kind of red colouring is being watched by Consumer Reports – red dye No. 3.

“Red No. 3 dye, also known as erythrosine, is a synthetic dye derived from petroleum, and is used in food and drinks to give them a kind of bright cherry-red color,” said Lauren Kirchner with Consumer Reports.

In the U.S., red dye No. 3 is prohibited in cosmetics but not in foods.

Last October, more than 20 advocacy groups, including Consumer Reports, signed a petition to prohibit its use in foods, dietary supplements and ingested drugs.

In Canada, red dye No. 3 is allowed in both food and cosmetics.

In a statement to CTV News Winnipeg, Health Canada said when used in food it must meet food-grade quality standards. However, when it comes to cosmetics, a spokesperson said: "Health Canada is actively monitoring the scientific evidence on this substance.”

Canadian food and cosmetic manufacturers are required to list food colours in the ingredients list.

But Khan said synthetic dye warning labels, like what’s required in the European Union, could be something to consider once there's more evidence to support it.

Health Canada said red dye No. 3 is not related to 'pigment red 3,' which is not permitted in food or cosmetics in Canada.

The International Association of Color Manufacturers, based in the U.S., told Consumer Reports there isn't enough evidence associating red dye No. 3 with behavioral problems, and maintains it is safe at the levels most people consume.