Housing assistance via the federal Housing Choice Voucher, formerly known as Section 8 , makes rent affordable and helps families avoid homelessness, putting parents in a better position to secure permanent employment.

Low-income subsidies for Medicare Part D make medication more affordable, and studies have demonstrated that reduced medication costs are associated with better adherence to treatment and improved health outcomes. It should come as no surprise, then, that people who take their prescribed medicines also have fewer missed days of work and less reliance on short-term disability.

Medicaid itself has been associated with a reduction in mortality, with a recent estimate predicting one life saved annually for every 239 to 316 adults gaining insurance.

While the benefits of these public assistance programs seem clear, even if one rejected this research we have a moral obligation to provide basic human services to legal immigrants. We shouldn’t shroud the truth: The regulation will physically harm immigrants. It will also inflict pain on their children, who may have the most to lose as their parents are pushed to partly forfeit health care, nutrition and shelter assistance. One in four children (19 million in all) in this country has immigrant parents, and nearly nine in 10 of these children are citizens.

Even without the rule going into effect, the fear surrounding it has magnified the calamity. In 18 states, nearly two-thirds of licensed providers for the federal Women, Infants and Children nutrition program have reported already seeing a decline in caseloads, some by as much as 20 percent. If this rule is put into effect, one million immigrants are expected to drop Medicaid.

To be clear, no immigrant should remove himself from public assistance programs, at least until the rule is made final, and we still have several steps before that would become a reality. And immigrants, even with the rule, would still be allowed a paltry 12 months of Medicaid in a three-year period before being labeled public charges. But this fear, stoked by our president and carried out by brutal regulations, may cause immigrants like my patients to shy away from the government’s helping hand for decades to come.

During the health care debates in 2010, opponents of expanding coverage frequently spoke about reform getting in the way of the doctor-patient relationship. What they don’t seem to understand is that my relationship with my patients is predicated on their ability to get insurance coverage like Medicaid. My ability to prescribe medications to treat diseases for the elderly is dependent on Medicare Part D. And my counsel about healthy food will fall on deaf ears if nutritional assistance is forgone.

Our government should not torture our nation’s must vulnerable immigrants by forcing them to choose between their citizenship status and their health. Immigrants should not have to give up food, shelter and health care to pursue the American dream.

Douglas Jacobs is an internal medicine resident at the Brigham and Women’s Hospital and Harvard Medical School.