For Ceyeissha McKim, it's all pretty simple:

"If I lose food stamps, I don't survive," said McKim, 26, a mother of three and a professional caregiver who works 25 to 30 hours a week in West Grove, Chester County.

Her eligibility for food stamps could one day disappear, thanks to proposed changes in the benefits program, known as the Supplemental Nutrition Assistance Program, or SNAP.

A bill in the U.S. House of Representatives would mandate enhanced work requirements for people receiving SNAP, denying benefits to those who work fewer than 20 hours a week.

It also would penalize people whose hours fall below that mark, making it much harder to regain food stamps.

Further, the proposed law would change guidelines that currently give states the ability to make SNAP benefits available to a wider pool of people, potentially throwing tens of thousands of Pennsylvanians off SNAP.

Many conservative legislators have said the proposed changes will ensure that able-bodied people who receive SNAP benefits are not freeloading.

Advocates for the poor, however, say the changes would hurt working people.

"The proposed law is just stacked against low-wage workers in so many ways," said Kathy Fisher, policy director of the Greater Philadelphia Coalition Against Hunger. "It will make people fall further into poverty."

Renee Gorski, 40, a mother of two in Norristown who works 25 hours a week in the office of a trucking firm, said: "This would be crushing. It would be more hardship without food stamps. Sometimes, in our slow season, I work just 15 hours a week. What will I do then?"

The House bill is the latest proposed version of the Farm Bill, which funds SNAP, currently at $68 billion annually. The Senate created its own version, which doesn't differ substantially from current guidelines. Both chambers are scheduled to come up with a final Farm Bill by Sept. 30.

The House legislation is sanctioned by Republicans and the conservative Heritage Foundation. It was written to "promote self-support among recipients," according to a foundation report.

"The bill represents a step toward an important goal: combining the principles of compassion and fairness in federal welfare policy," the report said. People who receive SNAP benefits who are physically able to work "would be required to take steps to support themselves."

Poverty advocates disagree.

First, they say, most of the people on SNAP are children, elderly, or disabled.

Second, lots of people who receive SNAP benefits work, and working people need those benefits, Fisher said, because so many jobs these days are part time and subject to unstable schedules and fluctuating hours.

Ultimately, increased work requirements "would do more harm than good," noted a report by the left-leaning Center on Budget and Policy Priorities "fueling increases in hunger and poverty and forcing states to develop large new bureaucracies" to determine whether people are working.

For years, there have been work requirements for SNAP.

Since 1996, people aged 18 to 49 without a child under age 18 have had to work at least 20 hours a week or be in school or job training to receive SNAP benefits. Anyone not following the rule would be limited to three months of benefits within a three-year period.

During hard times, such as the Great Recession, states were permitted to waive the rules in places of high unemployment. Philadelphia fell into that category.

The proposed bill would do away with the waiver, then expand the age of people required to work to 59. It also would require parents of children aged 6 and over to work, potentially creating serious child-care challenges for parents, advocates say.

And if people fall below 20 hours of work in a week, they could lose SNAP benefits for a year, the proposed new rules say.

Already disadvantaged by low wages and unpredictable hours, people working in part-time jobs in industries such as fast food, hospitality, and retail could be devastated, said Elizabeth Lower-Basch, a director of the nonprofit Center for Law and Social Policy (CLASP).

Meanwhile, if the waivers end, some 92,000 Pennsylvania residents — including 45,000 Philadelphians — would likely get kicked off SNAP, Fisher said.

Nationwide, the bill's changes would cause more than two million people to lose benefits altogether or have them reduced, according to the Center on Budget and Policy Priorities.

Because the House bill would also eliminate the flexibility state governments have to expand SNAP eligibility, many other people will have their benefits taken away, said Joel Berg, CEO of the nonprofit advocacy group Hunger Free America.

For example, nationwide, people are eligible for SNAP if they are making 130 percent of the poverty level, around $27,000 for a family of three. However, the old SNAP rules have allowed states to raise the level at their discretion. In the case of Pennsylvania, eligibility stands at 160 percent of poverty, or around $33,000 for a family of three.

The House bill would end that, throwing everyone between 130 percent and 160 percent of the poverty level off food stamps.

Critics also say that the House bill requires greater scrutiny of SNAP recipients, which means that states would actually have to spend more money expanding their bureaucracies, Fisher said.

And, while the House bill offers money to train people for work so they ultimately won't need SNAP, the stipends granted are woefully inadequate to train anyone for anything, she added.

Fisher contended that the ultimate plan by the House was to make getting SNAP so difficult that people would drop off its rolls, thereby reducing the cost of the program.

For their part, conservatives have said that they'd like to see SNAP benefits reduced across the United States

According to a Heritage Foundation report, "This reform … would promote self-support among recipients and generate significant savings."

Philadelphia Media Network is one of 19 news organizations producing Broke in Philly, a collaborative reporting project on solutions to poverty and the city's push toward economic justice. Follow us at @BrokeInPhilly