WASHINGTON — The Department of Health and Human Services on Monday announced a new effort to catalog the many additives in the U.S. food supply, most of which entered with little oversight.

Companies looking to add a new substance to human or animal foods will need to notify the Food and Drug Administration, and provide details on how they deemed the additive “generally recognized as safe,” or GRAS. Manufacturers with GRAS substances already on the market would need to let the FDA know for the first time how the additive is used — information that would be made public in a database, HHS officials said.

While companies would not need to prove existing additives are safe, something advocates have long pushed for, their notices would give the FDA a clearer log of the many chemicals Americans ingest through their food every day. Agency staff and outside researchers could then begin to understand which ones are harmful to human health.

“This is a major step forward,” said Vani Hari, who is known as the FoodBabe, and has been an adviser and ally in the administration’s food policy efforts.

HHS Secretary Robert F. Kennedy Jr. has railed against the opaque “GRAS loophole” for years, amplifying the critiques consumer advocates have made for decades. The current scheme has allowed thousands of chemical additives to enter the American food supply without any vetting of their health effects.

The result is that consumers may not know what they are eating, because even the FDA doesn’t known what food companies are putting in their products. Kennedy and his “Make America Healthy Again” movement called for the loophole to be closed, and fomented public distaste for chemical-laden foods.

Artificial dyes, for example, have become a sticking point as Kennedy pressured various companies to rid their snack foods of petroleum-based coloring. Some dyes have been linked to health problems in mice. (The Biden administration banned red dye no. 3 as a result.)

Monday’s announcement stops short of closing the loophole, the MAHA ideal. FDA Commissioner Kyle Diamantas was careful, on a call with reporters, to specify that the proposal would not establish “pre-market approval” of chemicals. Congress would need to amend the Food, Drug and Cosmetics Act of 1938 in order to give FDA that power.

Still, the mandatory notification system “closes a decades-old information gap,” he said. “The proposed rule advances and improves transparency and the agency’s oversight of the U.S. food supply while respecting the limitation to our authority.”

Once the notification of a new ingredient reaches the FDA, the agency will review it within 45 days to make sure it meets the requirements under law, per the proposal. Within 180 days, FDA will complete a more substantive review, and may ask manufacturers for more information or determine the application hasn’t met GRAS criteria, Diamantas said.

Jennifer Pomeranz, a public health lawyer who has studied the GRAS system, said the proposal marked a “significant change” that would protect consumers. Post-market review of substances that have already been added to foods is key, she said.

“Without this requirement there is no method for the FDA to identify their existence, as food companies do not disclose these self-GRAS ingredients to FDA, on food labels, or otherwise,” said Pomeranz, an associate professor of public health policy and management at NYU School of Global Public Health.

Others felt let down by the news.

“The proposed GRAS actions do not tackle the root causes of chronic diseases,” former FDA Commissioner David Kessler told STAT. The move by FDA would not address the refined carbohydrates and sweeteners that are found in so many ultra-processed foods, and which have been linked to metabolic disease, Kessler said.

“They’re not even tackling what’s in the food supply today,” he said.

Kessler filed a citizen petition a year ago asking the FDA to crack down on ultra-processed foods and classify refined starches as unsafe, out of GRAS. Such a change — which Kessler said FDA has the authority to do — would put the onus on food makers to prove refined carbs and sweeteners like high-fructose corn syrup are OK for human consumption.

Kennedy said in February he would act on Kessler’s legal petition, and sent its position to the White House, but nothing has come of that yet.

The GRAS proposal also left nutritionist and food-industry watchdog Marion Nestle underwhelmed. “That’s ALL??? What took them so long for something so simple and obvious?” she told STAT in an email. “This is an improvement, but the company is still responsible for the science and will still be hiring its own experts to say the additive is safe.”

Nestle also wonders whether the FDA has adequate staffing to review GRAS notifications. The agency had its ranks thinned out last year, including in food-related divisions. Previous administrations interested in tightening GRAS have expressed concerns about how labor-intensive and expensive such a program could be.

HHS officials did not say how much it would cost to implement the new review processes.

“Oh well, this is at least a step to getting a hold on what’s out there,” Nestle said.

HHS officials and MAHA supporters will gather at agency headquarters Monday morning for a “policy celebration” akin to the rallies Kennedy held after new dietary guidelines were unveiled earlier this year. The GRAS news will be front-and-center, though officials suggested more is on the way.

An FDA definition of ultra-processed food has been submitted for final review, they confirmed to reporters. It’s unclear how long that process will take. Officials declined to share more details on the definition, which has been in the works for over a year, and could generate a contentious battle between health officials and the food industry.

The GRAS proposal will be posted to the Federal Register on Monday, and will be open for public comment until early December.