Robert F. Kennedy Jr., the newly confirmed health and human services secretary, and Brooke Rollins, the new agriculture secretary, have both signaled that they favor stripping such treats from SNAP, the Supplemental Nutrition Assistance Program.

Kennedy has been most vocal, calling for the government to stop allowing the nearly $113 billion program that serves about 42 million Americans to use benefits to pay for “soda or processed foods.”

“The one place that I would say that we need to really change policy is the SNAP program and food stamps and in school lunches,” Kennedy told Fox News host Laura Ingraham last week. “There, the federal government in many cases is paying for it. And we shouldn’t be subsidizing people to eat poison.”

In one of her first interviews after being confirmed, Rollins said she looked forward to working with Kennedy on the issue.

“When a taxpayer is putting money into SNAP, are they OK with us using their tax dollars to feed really bad food and sugary drinks to children who perhaps need something more nutritious?” Rollins said. “These are all massive questions we’re going to be asking and working on in the coming months and years.”

But removing certain foods from SNAP — known for years as food stamps — isn’t as simple as it sounds.

The program is run by the USDA, not HHS, and is administered through individual states. It is authorized by the federal Food and Nutrition Act of 2008, which says SNAP benefits can be used for “any food or food product intended for human consumption,” except alcohol, tobacco and hot foods, including those prepared for immediate consumption.

Excluding any foods would require Congress to change the law — or for states to get waivers that would let them restrict purchases, said Katie Bergh, a senior policy analyst for the Center on Budget and Policy Priorities, a nonpartisan research group. Over the past 20 years, lawmakers in several states have proposed stopping SNAP from paying for bottled water, soda, chips, ice cream, decorated cakes and “luxury meats” like steak.

“None of those requests have ever been approved under either Republican or Democratic presidents,” Bergh said.

In the past, Agriculture Department officials rejected the waivers, saying in a 2007 paper that no clear standards exist to define foods “as good or bad, or healthy or not healthy.” In addition, the agency said restrictions would be difficult to implement, complicated and costly. And they might not change recipients’ food purchases or reduce conditions such as obesity.

Anti-hunger advocates point to research that shows SNAP recipients are no more likely than other low-income Americans to buy sugary drinks or snack foods. And they say that limiting food choices undermines the autonomy and dignity of people who receive, on average, about $187 per month — or about $6.16 per day, according to latest figures.

“This is just another way to cut benefits,” said Gina Plata-Nino, a deputy director at the Food Research and Action Center, a nonprofit advocacy group. “It’s like, how do we restrict people more? How do we stigmatize them more?”

Bills are pending in Congress and in several states to restrict SNAP benefits from paying for soda, candy and other items.

Rep. Josh Breechan, an Oklahoma Republican, sponsored the Healthy SNAP Act.

“If someone wants to buy junk food on their own dime, that’s up to them,” he said. “But what we’re saying is, ‘Don’t ask the taxpayer to pay for it and then also expect the taxpayer to pick up the tab for the resulting health consequences.’”

One SNAP recipient said she uses her monthly $291 benefit to buy necessities such as meat, oil, milk and coffee. Martina Santos, 66, of New York City, supplements those foods with fresh vegetables and fruits from a pantry run by the West Side Campaign Against Hunger, where she’s also a volunteer. Because she has diabetes and other health conditions, she said she understands the importance of using the benefits only for nutritious options.

“For me, SNAP is to be used toward healthy food to get people to avoid all the disease they’re having around right now: obesity, diabetes, high blood pressure,” Santos said.

In Kansas and elsewhere, bills that would ban soft drinks and candy highlight some of the challenges of such changes.

Several pending bills seek to keep SNAP from paying for soft drinks, but they would continue to allow drinks containing milk, milk alternatives like soy or almond milk, or drinks with more than 50% vegetable or fruit juice. Candy is characterized as any unrefrigerated, flourless preparation of “sugar, honey or other natural or artificial sweeteners in combination with chocolate, fruits, nuts or other ingredients or flavorings in the form of bars, drops or pieces.”

By that definition, Kit Kat and Twix bars, which contain flour, wouldn’t be banned. And juices that contain high amounts of sugar, but are more than half fruit juice by volume, would be allowed.

Such conundrums have stymied changes to the SNAP program for decades. But this moment could be different, said Dr. Anand Parekh, chief medical officer of the Bipartisan Policy Center, a think tank based in Washington, D.C.

The momentum behind Kennedy’s “Make America Healthy Again” movement could spur a new focus on solutions to poor diets that account for leading risk factors for early disease and death.

“When we talk about the SNAP program, we have to remind people that the ‘N’ stands for nutrition,” Parekh said. “It’s about time that both parties can come together and see what are the innovations here to improve diet quality and nutrition.”

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