To market a new food or color additive, a manufacturer or other sponsor must first petition the FDA for its approval. Since 1999, indirect additives have been approved by a premarket notification process requiring the same data as was previously required by petition.
But Leake and Hari cite a 68-page report from the Center for Science in the Public Interest, "Food Dyes: A Rainbow of Risks," which outlines various studies on the health effects of food coloring.
The center was founded by scientists when consumer and environmental protection awareness was growing in 1971. It advocates for nutrition and health, food safety and alcohol policy.
The report was based on government studies from the National Toxicology Program and recommends removing yellow 6 from the market.
Both dyes used in the Kraft product contain benzidine 4-amino-buphenyl, a manmade product derived from petroleum. In a "too brief" mouse study, yellow 5 showed risks of hyperactivity in children, according to the report; yellow 6 was associated with adrenal and testicular tumors and no studies were done in utero.
Hari said she was inspired to see if there were other products that contained additives banned overseas.
"It was shocking to see hundreds of ingredients that were banned in other countries and were used in American products," she said.
"A can of Pringles in the U.S. looks the same as in the U.K. or Europe and the ingredients are totally different."
For example, French fries at McDonald's in the United Kingdom contained only potatoes, oil and salt. In the U.S., they contain a preservative.
This is not the first petition to address food additives. Last fall, Sarah Kavanagh, a 15-year-old student in Mississippi, started a Change.org petition to get PepsiCo to stop using brominated vegetable oil in its Gatorade.
The ingredient, which was used to prevent some flavors of the drink from separating, has been associated with possible neurological disorders and altered thyroid hormones. It has been banned in some other countries.
The petition attracted more than 200,000 backers. Last month, Gatorade announced that they would be removing the ingredient, but said the decision wasn't in response to Sarah's petition.
Hari said she was "inspired" by the teen's petition. "Lisa and I were really encouraged to take the next step and create change."
Leake said she no longer lets her children eat Mac & Cheese and makes sure they have a healthy diet filled with fresh ingredients. But, she added, if the U.K. version of the product were available in the U.S., she would allow it at the dinner table again.
As for food dyes, she said, "They provide no value to the food and no nutrition, but they do pose a risk. It's a no-brainer."