New research provides evidence that immigrants to the United States are far less likely than US-born individuals to experience a number of psychiatric disorders. The study appears in the journal Psychiatry Research.

“Over the last several years, my colleagues and I have conducted more than two dozen national studies focused on the health and well-being of immigrants in the United States,” said study author Christopher P. Salas-Wright of Boston University.

“Research on immigrants is absolutely critical as the United States is home to a very large number of immigrants — at present, roughly 40 million foreign-born individuals live in the US, and one in four people in the US is either an immigrant or the child of an immigrant.

“Immigration is expected to be responsible for the majority of population growth over the next 30 years and has become a hot-button issue in our national discourse. Paying attention to the mental health of immigrants, in particular, is important because we know that adjusting to life in a new context and culture can be very stressful.”

For their study, the researchers analyzed data from the National Epidemiologic Survey on Alcohol and Related Conditions (2012–2013), a nationally representative survey of 36,309 adults in the United States. Along with face-to-face structured psychiatric interviews, the survey also asks participants about their immigration status.

The researchers found that immigrants were significantly less likely to meet the criteria for an anxiety, depressive, and trauma-related disorder. The findings provide support for the healthy migrant hypothesis.

“This study provides clear evidence that, despite the stresses of migration and adapting to life in a new country, immigrants are far less likely to have mental health problems compared to people born in the United States,” Salas-Wright told PsyPost. “This was the case for immigrants from Africa, Asia, Europe, and Latin America, as well as from top immigrant-sending countries such as Mexico, China, India, and El Salvador. We also found that immigrants were far less likely to report that their mother and father struggled with anxiety or depression.”

“We argue that this is likely because migration is not random — rather, people who are motivated and able to pick up everything to start a new life in a foreign country are more likely to be physically and psychologically healthy compared to those who do not migrate.”

“There is a lot of support for this idea, and scholars have even coined a term for it: the healthy migrant effect. The basic notion here is that self-selection is a core feature of migration, and that those who self-select for migration tend to be part of a uniquely hearty and healthy subset.”

The study controlled for the effects of key sociodemographic and parental psychiatric history confounds.

The researchers also found that the risk for psychiatric problems was lowest among those who migrated to the United States after age 12.

“Although our results were quite clear cut, we did find one important exception: individuals who migrated during childhood (age 11 or younger) were, on average, no more or less likely than people born in the US to have mental health problems as adults,” Salas-Wright explained.

“This is a similar pattern that we have seen with other outcomes—like substance use and obesity—where those who migrate as children tend to more closely resemble persons born in the US than those who migrate later on in life.”

“Scholars are still trying to pinpoint exactly why this is the case, but there are several possibilities. One is that people who migrate as children tend to take on many of the practices and values of their new country faster than those who migrate as teenagers or adults,” Salas-Wright said. “It may be that, in ‘becoming more American’ in how they think and act, immigrants also come to more closely resemble US-born individuals in terms of mental health risk.”

“It is also quite possible that those who immigrate as children are more likely to be negatively impacted by bullying, discrimination, and other migration-related stressors that can place them at risk for mental health problems like depression and anxiety.”

The new findings dovetail with previous research.

“Our findings for mental health among immigrants are very similar to what we have seen for other health and behavioral problems,” Salas-Wright told PsyPost. “That is, what we have learned about immigrants’ mental health matches up with other studies showing that, compared to people born in the United States, immigrants are substantially less likely to: misuse alcohol and other drugs, commit crimes and enact violence, and take part in risky or dangerous behaviors in general.”

“While some immigrants certainly have mental health and behavioral problems, a large and growing number of studies makes clear that immigrants are far less likely to have such problems than those born in the United States.”

The study, “Immigrants and mental disorders in the united states: New evidence on the healthy migrant hypothesis“, was authored by Christopher P. Salas-Wright, Michael G. Vaughn, Trenette C. Goings, Daniel P. Miller, and Seth J. Schwartz.