rewrite this title Why Natural Food Dyes Aren’t Always Safer

Since becoming Secretary of Health and Human Services (HHS), Robert F. Kennedy Jr. has taken aim at coloring compounds in foods, drinks, and medical products, claiming that they can compromise people’s health. In the recently released Make America Healthy Again report, Kennedy and others mention food colorings and note data connecting some to behavioral issues in children. HHS has already taken steps to ban some synthetic food dyes and replace them with natural-based alternatives, and plans to introduce more naturally derived options.

Synthetic dyes are generally made from petroleum and concocted in labs. Their rich and deep shades are often not found in nature. (Think bright-red Jell-O—courtesy of Red 40—and Mountain Dew, made neon by Yellow 5.)

The transition from artificial food dyes to natural alternatives had already begun well before the MAHA report, with the rise of organic and more “natural” options. In 2016, Kraft removed artificial colors, flavors, and preservatives from its mac & cheese, and General Mills announced it would remove such dyes from its cereals and other foods provided to schools this summer, while J.M. Smucker Co. and Kraft-Heinz pledged to stop using synthetic dyes in their products by 2027.

Since January, the U.S. Food and Drug Administration (FDA) has approved four new color additives for foods and banned one, and announced a plan to work with food makers to voluntarily phase out all petroleum-based synthetic dyes from the food supply by the end of 2027. Many states—such as California, West Virginia, and Texas—are committing to a similarly rapid phase-out of synthetic dyes, particularly in foods provided through their school nutrition programs.

But industry experts say that switching to natural colorings comes with a unique set of challenges—and may not always be safer for human health. Here’s what to know about the food colorings coming soon to your pantry and fridge.

Just because they’re “natural” doesn’t make them safer 

The FDA has different processes in place to evaluate synthetic and natural dyes. Synthetic colorings are highly regulated, and companies are required to send samples of each batch of color that they make to the FDA for inspection and assurance that the colorings comply with strict safety specifications set by the agency.

Natural colorings, on the other hand, are subject to a self-certifying process in which the burden of inspecting falls to the manufacturers to attest that their additives comply with specified regulations, says Paul Manning, chairman and CEO of Sensient Technologies, one of the biggest manufacturers of natural food-color additives in the U.S. that also produces synthetic food colorings.

There are now four natural colorings approved for use in food: Galdieria extract blue, which comes from red algae; butterfly pea flower extract, which produces shades from bright blue to deep purple and green; calcium phosphate, which makes white for candies and ready-to-eat chicken; and gardenia blue, which is extracted from the gardenia fruit.

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But their natural sources of color do not necessarily mean that they are safer or free of potentially harmful compounds. Natural sources may be treated with pesticides and herbicides, and are also prone to contamination with bacteria and other pathogens, Manning adds. To strip natural products of these contaminants, manufacturers process them with various solvents—some of which could remain in the final coloring and contribute to negative health effects, Manning says.

One other potential downside: it generally takes more natural color than synthetic color to make the same shade in a final food. “Typically it takes eight parts of a natural color to achieve the same color outcome in a finished food product,” says Manning.

Making natural coloring safer

To better understand how prevalent such contaminants are in natural colorings, Sensient conducted tests on raw-material products from growers and found “alarmingly high failure rates” of unsafe amounts of solvents and pesticides, says Manning. “When we told them they were not within specifications set by U.S. law and that we did not want them, more often than not, we heard that they would just sell to somebody else.”

In an effort to distinguish its standards for natural food colorings, Sensient developed Certasure, a certification program that it uses to evaluate the raw materials it sources for natural food dyes. A Certasure certification means that natural coloring has been inspected and has passed tests to be deemed safe for human health.

Challenges in transitioning away from synthetic dyes

“If everybody in the U.S. wanted to convert to natural colors tomorrow, it could not be done with the existing supply chain,” says Manning. Currently, he says about 60% of the company’s food-coloring products are natural, and 40% are synthetic.

There are manufacturing challenges. “Supply needs time to catch up with demand,” he says. That’s because the plants and crops that are the source of naturally derived dyes not only require time to grow, but require planning to secure farmers who know how to grow them in large enough quantities. Manning says generally it takes about five years to scale up a new source of natural coloring.

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Part of that ramp-up relates to the fact that very few of the natural color additives recently approved in the U.S. are grown in the U.S., so land, resources, and farmers need to be recruited and brought on board from around the world to meet the anticipated higher demand.

Sensient, for example, makes the blue-hued butterfly pea flower extract , which grows in Southeast Asia. Recently raised tariffs on overseas products, as well as continued growth in demand for natural food colorings around the world, could place an even greater burden on companies switching from synthetic to natural dyes, says Manning. (About 80% of Europe’s food market relies on natural colorings, for instance.)