According to the Journal of the American Medical Association, roughly one in six medical professionals are foreign-born, many working in rural or underserved communities. These areas struggle to attract U.S.-born med school grads.

The study, which estimated the proportion of non-US-born and noncitizen healthcare professionals in the U.S. in 2016 by using self-reported data from the Census Bureau’s 2016 American Community Survey. It found that almost 30 percent of physicians were foreign born while dentists were 23.7 percent and registered nurses 16 percent. The survey highlights how much the U.S. relies on immigrants to properly function and support itself.

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