Food dyes are ubiquitous, in everything from cereals and salad dressings to toothpaste and even medicine.

They've become hard to avoid, despite the fact that some studies have found they can have adverse effects on children.

In October 2023, the State of California announced it will ban Red Dye No. 3 in 2027, after a report linked it to hyperactivity and other neurobehavioral effects in children.

The Office of Environmental Health Hazard Assessment (OEHHA) published its final report in 2021, titled "Health Effects Assessment: Potential Neurobehavioral Effects of Synthetic Food Dyes in Children."

The study notes "current human epidemiologic evidence supports a relationship between food dye exposure and adverse behavioral outcomes in some children, both with and without pre-existing behavioral disorders."

The issue has prompted a Calgary mother to launch an online petition calling for the removal of artificial colour from children's medicine in Canada.

Laura Combden says her daughter Bernadette experiences adverse behavior due to food dye exposure.

Combden says her daughter first began displaying extreme emotional episodes in late 2022.

"Bernadette loses control of all of her emotions and she gets this pent-up aggression. She cries and screams and kicks and flails," she said. "She has no control over her body."

"She was hitting and kicking and punching and knocking things over. It would last about 40 minutes, then she would come down and she would just be spent for hours afterwards.

"It turns out, it's a neurological response," Combden said. "There's something she cannot control happening inside of her brain."

Laura Combden, Bernadette LeibelCombden says Bernadette did not begin displaying any symptoms until just after her fifth birthday.

"She used to be able to consume food dye at birthday parties, at special events, and she would have cupcakes, and she would have candy" said Combden. "Not overly, just a regular amount that any three and four year old would have."

Months later, after she had a candy cane at a Christmas market, her mother began to suspect food dyes were the cause of her outbursts.

"We tried to cut out red first, and then we quickly learned that it was all dye… it was red, yellow, blue and white, which is called titanium dioxide," said Combden.

"The most heartbreaking part of discovering that she's allergic to this was that it was in her toothpaste. We had fed it to her morning and night."

Laura Combden, Bernadette LeibelCombden has now eliminated synthetic food dyes from her daughter's diet, but says keeping them away from her completely is made difficult by the fact many children's medications contain the colourings.

'No nutritional benefit'

Waliul Khan, a professor in the department of pathology and molecular medicine at McMaster University in Ontario, studies food dye additives.

"As far as I know, these dyes are actually not beneficial. These dyes have no nutritional benefit," said Khan, whose research focuses mainly on Red Dye 40, or allura red, found in candies, cereals, some dairy products and soft drinks.

"We found that this red dye is increasing colitis, interrupting the barrier function in the gut. This is an important finding and it actually suggests that we should do more research, particularly involving humans related to humans."

"I think it will be better to minimize the intake of all (synthetic food dyes)."

While Red Dye No 3 will be banned in California in 2027, it remains an accepted food additive through the rest of the United States, even though it is prohibited in cosmetics.

Late last year, 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 written statement sent to CTV News, Health Canada said:

"In 2018, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) re-evaluated the safety of erythrosine (Red Dye No. 3) as a food additive and concluded that, for all age groups, dietary exposure to erythrosine does not present a safety concern."

Health Canada did note that the US FDA has received a petition seeking to eliminate it from food, but noted:

"Health Canada has not received a similar request. However, as with any food additive, if new scientific evidence becomes available demonstrating that erythrosine is unsafe for use as a food colour, Health Canada will no longer permit it to be used for this purpose."

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."

Combden doesn't buy that industry explanation, saying for her the evidence is clear: since eliminating food dye additives from her daughter's diet, the young girl's episodes have vanished.