The Trump administration said it’s taking first steps in strengthening rules over ingredients food companies have long added to their products with minimal oversight.

Under a proposed rule announced Monday, manufacturers will have to notify the Food and Drug Administration when they deem additives as “generally recognized as safe,” also known as GRAS, as well as provide information on existing additives.

But critics say that while this is a good first step, the proposed rule won’t prevent manufacturers from adding new ingredients to foods, nor will it remove the many thousands of additives already in foods.

The GRAS designation, which began in the 1950s, was meant to simplify the use of common ingredients like paprika, garlic and vanilla and avoid a lengthy approval process while also freeing up the FDA’s limited resources. Companies are not required to tell the FDA when deciding what they consider GRAS.

Critics, including public health experts and food scientists, have long said the industry has exploited the rule to introduce thousands of unstudied chemicals into the nation’s food supply, potentially endangering public health.

Deeming an ingredient GRAS does not necessarily make it so, and the FDA has banned certain ingredients from food after evidence emerged that they might harm health. These include Red No. 3, a synthetic dye that gives foods and drinks a bright cherry red color but has been linked to cancer in animals, and brominated vegetable oil, often used in citrus-flavored drinks, which has been linked to liver, heart and brain damage.

“Over time, that exemption has become the loophole, and the vast majority of substances have been submitted via that loophole without public disclosure or of the information safety,” Dr. Dariush Mozaffarian, director of the Food Is Medicine Institute at Tufts University, said during a media event Monday with Health Secretary Robert F. Kennedy Jr.

The proposed rule would require companies to notify the FDA when they deem substances as GRAS. The notices would be made public. For substances that already have a GRAS designation, the proposed rule would ask companies to submit data about how those ingredients are used.

“The new rule does not prevent companies from self-affirming the safety of their ingredients,” said Alyssa Moran, deputy director of the Center for Food and Nutrition Policy at the University of Pennsylvania. “It does require mandatory notification, but my understanding is that there’s not even a timeline for notification, so companies can introduce these ingredients and then eventually notify FDA.”

“It’s just quite misleading to say we’re going to close the GRAS loophole, and then to still allow companies to self-affirm the safety of their ingredients,” Moran added.

Jennifer Pomeranz, associate professor of public health policy and management at the New York University School of Global Public Health, said the proposed rule was “an incredibly important first step” but said more work is needed.

“What data is going to be required to be submitted about the ingredients already in the food supply?” Pomeranz said. “It has to be enough for us to see that it’s safe. It can’t just be a name of an ingredient and its uses.”

Stephanie Harris, chief public policy officer for the Food Industry Association, which represents grocers and other food suppliers, said that the GRAS proposal is “an important step” but shows limits of what the FDA can do to make such reforms, legally.

“Congress should act this year to establish a nationally uniform, science-based framework for ingredient transparency that strengthens FDA’s role, avoids a fragmented state-by-state patchwork and provides consumers and the food industry with clarity and confidence,” Harris said in a statement.

During the media event, Kennedy also announced a federally recognized definition for ultraprocessed foods is under “final review” but did not provide the text of the definition. A spokesperson for the Department of Health and Human Services did not give a timeline for when that would be made public.