People wait in line at an emergency food pantry in Brooklyn in 2014. (Spencer Platt/Getty Images)

Millions of Americans could go hungry if President Trump moves forward with a draft executive order that restricts the welfare benefits available to immigrants, according to experts in immigration law.

That’s because the order would restrict access to needs-based nutrition programs, like SNAP and WIC, that are currently accessed by millions of first-generation immigrants both for themselves and on behalf of their second-generation, citizen children.

According to a recent analysis by the National Academies of Sciences, 45.3 percent of all immigrant-headed households with children use a food assistance program. Eighty-eight percent of all children living with immigrant parents are themselves U.S. citizens.

“He would literally be taking food out of the mouths of babes,” said Kevin Appleby, the senior director of international migration policy at the Center for Migration Studies, “and some of them would be U.S. citizens.”

The draft executive order, which leaked publicly on Tuesday, seeks to reduce the number of immigrants using government assistance. It’s unclear when Trump plans to sign the order, if at all, and whether it will be signed in its current form. Even if signed, it could take time for government agencies to act on the president’s orders, and their eventual actions might not play out as implied in the draft order.

But as it is currently written, the draft order instructs the departments of State and Homeland Security to overhaul their definition of a “public charge” -- a person who is likely to become dependent on government help after immigrating. It would also make immigrants who use public benefits “for which eligibility or amount is determined in any way on the basis of income” subject to possible deportation.

Under long-standing policy, the government has not considered receipt of nutrition, medical or housing benefits when evaluating if someone has become a public charge for deportation purposes. While the federal government has prohibited even legal immigrants from accessing many of these programs as soon as they arrive in the United States, some states allow access if they have children under 18 years old. And some federal benefits, such as WIC, the school lunch program and emergency Medicaid, are not restricted. Practically speaking, almost no one is deported for receiving such benefits unless there’s evidence they deceived the government at the time they immigrated.

The executive order could hypothetically change that, barring potential immigrants who may need nutrition assistance and making the use of these programs a deportable offense. Advocates say that will cut the number of people who apply for SNAP, WIC and reduced-price school lunch, even when they, or their children, are legally eligible for them.

“It’s a radical change to 100 years of case law that say the exact opposite,” said Charles Wheeler, the director of training and legal support at the Catholic Legal Immigration Network. “It’s like imprisoning someone for failing to pay a debt. Didn’t we take care of that a long time ago?”

Immigrants already face restrictions on the welfare benefits they can receive, Wheeler said. Since the late 19th century, it has been formal U.S. immigration policy to deny admission to people who seem likely to need government aid to subsist, usually because they’re unable to work or require institutionalization. (Critics contend that, in recent years, this policy has not been enforced.) When an immigrant comes to the United States through a familial connection, that sponsor must also sign an affidavit promising to take responsibility for the immigrant's finances.

Once they are admitted to the United States, legal immigrants cannot apply for cash benefits -- including Temporary Assistance for Needy Families (TANF), Social Security and Medicaid -- until they have been in the country for five years. Immigrants are immediately eligible for food stamps, or SNAP, if they have young children, and data from multiple sources suggests that many households take the government up on that benefit. However, according to the Department of Agriculture, the SNAP participation rate among eligible noncitizens is already significant lower than it is among eligible citizens.

“There is a perception that participating in SNAP could affect immigration status … but this is not true,” the department writes in its guidance to noncitizens. “It is important for non-citizens to know they will not be deported, denied entry to the country, or denied permanent status because they apply for or receive SNAP benefits.”

Trump’s draft order could, of course, change that.

History suggests such a move could have significant consequences for public health. In 1996, President Bill Clinton signed the Personal Responsibility and Work Opportunity Reconciliation Act, the welfare-reform law that first established the five-year wait time for cash benefits for immigrants. In the years following implementation, immigrant use of public benefits fell off dramatically, prompting Harvard University economist George Borjas to take a closer look at the numbers. He found that for every 10 percent drop in the fraction of the immigrant population that received public assistance, there was a 5 percent increase in the number of households classified as “food insecure.”

Borjas recently ran the numbers on immigrants and welfare again: In 2016, 8.9 million U.S. households were headed by a noncitizen. Of those, almost 42 percent received Medicaid, food stamps or cash assistance.

“Put bluntly,” he wrote, “taking the public charge provisions of immigration law seriously could potentially affect 3.7 million households, making the recent kerfuffle over a relatively small number of refugees look like small potatoes.”

Of course, such a dramatic turn in U.S. immigration policy would also save a lot of money on entitlements -- something that American voters are perennially concerned about. Polls show that immigrants’ receipt of welfare benefits remains a national anxiety. And while it's impossible to calculate an exact number for how much taypayers could save, given the available data, numbers from the National Academy of Sciences suggest it could be in the ballpark of $19 billion.

That’s just in the short run, though -- and advocates warn that poverty, and particularly food insecurity, have long-term implications. According to work by researchers at the National Cancer Institute, the Boston University School of Medicine and other institutions, children who don’t get enough to eat are more likely to develop chronic health conditions and to require hospitalization. Among adults, hunger frequently contributes to less productivity -- as well as social isolation and illness. The liberal Center for American Progress estimates that in 2010 hunger cost the U.S. health-care system $130.5 billion.

“With this sort of thing,” Appleby said, “there are unintended consequences.”

More from Wonkblog:

What it’s like to live on $2 a day in the United States

What happens when a family runs out of food stamps

The controversial reason tens of thousands of people just lost their food stamps