(CNN) The Trump administration's plans for food stamps could cost more than 750,000 people their benefits, and most of these folks are among the poorest of the poor.

The administration wants to make more Americans work for their food stamps by limiting states' ability to seek waivers from the current employment requirement. More than three-quarters of a million people could fall off the rolls, according to the Department of Agriculture.

The proposal, however, would hit very poor Americans, researcher Karen Cunnyngham told a House subcommittee Wednesday. The average monthly income of this group is $557, or 43% of the poverty level. Only 11% had jobs, but they didn't work enough to satisfy the proposed requirement, according to Cunnyngham, an associate director at Mathematica, a policy research firm.

The Supplemental Nutrition Assistance Program, as the food stamp program is formally known, already requires non-disabled, working-age adults without dependents to have jobs. They can only receive benefits for three months out of every 36 months unless they work or participate in training programs at least 20 hours a week.

But states can waive that time limit in areas with high unemployment or where there is an insufficient number of jobs, as defined by the Department of Labor.

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