If you were looking for another reason to ease immigration policy, here’s a pretty good one: a new Harvard study shows that immigrants contribute more money to Medicare than they get back in benefits.

According to the study, the American-born population generated a deficit of $28 billion from 2002 to 2009. Immigrants generated a surplus of $115 billion during that same period. These findings should disabuse anyone who still believes that immigrants take from government programs without contributing anything. (This isn’t news to those who follow the topic closely, but there’s a lot of bad scholarship out there asserting otherwise.)

The simple reason for this is that immigrants pour into the workforce much more than into the ranks of our retirees. While the working-age to retirement-age ratio of U.S.-born individuals is 4.7 to 1, the study calculates the ratio for immigrants as being 6.5 to 1. The ratio for noncitizen immigrants was even higher, at 12.4 to 1.

The fact that so many immigrants are of working age should prompt us to want to have them contributing to Medicare and other government programs. This boon to our working age numbers, coupled with a study suggesting that immigrants tend to use fewer medical services, should be enough to convince even the most ardent defenders of a walled country of the need to keep the United States an attractive place for immigrants.

If we choose to make it increasingly difficult for immigrants to gain legal status, we risk only further undermining Medicare’s precarious state. According to the authors of the Harvard study, the recent decrease in Mexican immigration combined with the distending aging population may means a decrease in the immigrant working-age to retirement-age people ratio. In other words, the Medicare trust fund will be swamped, depleting at an even quicker pace without the aid of the immigrant working-age population.

If we knew that the Medicare program had a future to it, I would dismiss the finding like some of my colleagues from other institutes. The truth of the matter is that immigrants are a vital part of what sustains the very programs they sometimes don’t benefit from. Getting them on the books and in the programs, all while providing them with legal status, may be the best option until politicians, those same ones who at times lambast immigrants, figure out what to do with Medicare.