The Food and Drug Administration has temporarily loosened labeling and information rules for food manufacturers for the fifth time during the novel coronavirus pandemic.

The changes are intended to ease manufacturers’ supply-chain snags, but advocacy groups say they are concerned that the changes will become permanent and that they will present problems for consumers concerned about tracking the provenance of their food.

The new guidance allows manufacturers to substitute hard-to-source ingredients in their products without changing the label. And it allows vending machine operators latitude to omit calorie information for foods sold.

Advocacy groups say the guidance, announced Friday, makes it more difficult for people with food allergies to be confident that their food won’t make them sick. It walks back some of the advances vending machines have made in the past year in offering more healthful choices.

“We have no objection to temporary flexibilities in this moment, but we view with suspicion the notion that you’d want to continue those after the emergency,” says Laura MacCleery, policy director of the Center for Science in the Public Interest. “They say they will take comments and consider an extension beyond the public health emergency.”

The FDA said the changes to the guidance were temporary and intended to address the public health emergency.

“The food industry has informed us that there are supply disruptions or shortages for some ingredients. As a result, manufacturers may need to make formulation changes, such as omissions or substitutions of minor ingredients,” FDA spokesman Peter Cassell said in an email. “To address this situation, and to continue to support the food supply chain during this emergency, the FDA is issuing guidance to industry to provide temporary flexibility for manufacturers to make minor formulation changes in certain circumstances without making conforming label changes.”

Other temporary changes that the FDA has issued since the start of the pandemic address nutrition labeling on food packages, menu labeling at fast-food chains, and two involving the packaging and labeling of eggs. These rules have eased requirements for nutrition fact labeling on restaurant food repurposed for retail sale and have included cryptic guidance for food manufacturers with links that don’t work.

The fifth rule change eases requirements on vending machine operators to provide calorie information for foods sold during the pandemic. And it says that a manufacturer may swap secondary ingredients so long as the stand-in “does not cause any adverse health effect (including food allergens, gluten, sulfites or other ingredients known to cause sensitivities in some people, for example, glutamates).”

Cassell says the formulation changes should be consistent with general factors such as safety, including food allergens, and prominence of the ingredient.

But for the estimated 32 million people in the United States with food allergies, “the devil is in the details,” Dave Bloom, chief executive of SnackSafely, a food allergy organization, wrote in a blog post. “The guidance goes on to introduce numerous loopholes that are of concern to members of the food allergy community.”

Betsy Booren, senior vice president of regulatory and technical affairs at the Consumer Brands Association, a trade group formerly known as the Grocery Manufacturers Association, says that the FDA changes reflect a desperately needed flexibility to reallocate foods and alleviate hiccups in supply chains during the pandemic.

“The [Department of Agriculture] and FDA have been really proactive to get food that was in the food service arena and transferring it to retail,” she said by phone. She says that disruption in international supply chains for spices and other ingredients have forced manufacturers to find new suppliers and swap ingredients.

“This guidance was the FDA recognizing that there could be some minor changes that do not impact food safety,” Booren said. “To change a label takes upwards of two years for a food company — doing the analysis, sending products to the printer — all that takes time. The FDA is allowing digital disclosures, stickers and smart labels.”

The FDA says temporary substitution of certain oils, such as canola for sunflower, may be appropriate without a label change because they contain similar types of fats. And with flour in short supply, unbleached flour can be substituted for bleached flour without a label change. Manufacturers now have the flexibility to substitute spices or vegetables without alerting consumers because of these new guidelines.

And for vending machines, providing calorie information is no longer required, although it is encouraged.

There are 4 million vending machines in the United States. Right now, the industry has seen a major shift, says Roni Moore, vice president of marketing for National Automatic Merchandising Association, the trade group representing the $25 billion vending machine industry.

Those in offices and other workplaces, in schools and in malls have spent the past two months in suspended animation, their Cool Ranch Doritos and Duchess honey buns going nowhere until regular work and school activity resumes. But conversely, she says, vending machines in 911 call centers, police stations, firehouses and medical centers are busy.

“Particularly during the pandemic, first responders are looking for the path of least resistance: Get me food and caffeine now,” she said by phone. “In many cases, there has been nowhere else to go during the pandemic, and vending machines offer low-contact delivery.”

She says the association sent a letter to FDA Commissioner Stephen Hahn requesting flexibility to change inventory when feeding first responders.

Mike Haller, a food safety technical manager for UL, a third-party safety company that conducts food audits, says these FDA changes are minor and intended to protect manufacturers from liability over undisclosed formulation changes.

“If a company says ‘it’s made with real butter,’ they have to stick with that,” he said. “But if a company doesn’t have vanilla extract for their chocolate chip cookies, they can substitute a minor ingredient like that. They are balancing these changes with disruptions in the food supply.”

Although he says he’s not concerned about allergens going undisclosed, people with dietary restrictions such as avoiding salt may not be privy to formulation changes that potentially affect them.

“They could change things like that,” he says. “It’s always good to ask.”

Food industry watchdogs argue that it’s unclear whom and how to ask, and many are concerned that the policy changes could become permanent as part of a broader push toward deregulation by the Trump administration.

“Our intention is to hold the FDA to a calendar so that these changes aren’t permanent,” MacCleery said. “The important thing is everybody know, and it be clear, that after this emergency is over that these regulations that have been the subject of so much public effort and deliberation come back into play. This shouldn’t be a reason things get watered down permanently.”