As Robert Lewis Jr. predicted, America is becoming a more hostile and racist place under President Donald Trump.

The week after the election, I met Lewis, an African-American retiree and a longtime civil rights activist, on a reporting trip to Concordia, Louisiana. Lewis told me he was afraid that prejudice — and any fragile gains in basic civil rights for black people — was about to grow worse under the new administration.

Trump, Lewis said, with visible distress on his face and in his voice, “[is] only going to make those racist skinheads, the KKK come out. The racists feel like they have a man in office who is supporting 'em, backing 'em up."

Health researchers are now confirming Lewis’s fears. In a new literature review published Wednesday in the New England Journal of Medicine, the authors looked at the growing body of research on big political events, like elections and 9/11. They found people with racist sentiments have been emboldened since the 2016 election, and that anxiety and stress are on the rise. They also found that premature births and deaths, and an increased risk for disease, were part of a package of worrisome health consequences that might arise after the 2016 election.

“There is a steady drumbeat of incidents of hostility in the news,” said lead author David Williams, a professor at the Harvard T.H. Chan School of Public Health, “So there is a pressing need to make health care providers aware of the health consequences.”

I asked Williams to explain how elections can alter people’s health, why political events can lead to everything from an uptick in heart disease to premature births, and what health trends may arise after 2017. The conversation that follows has been edited for length and clarity.

Julia Belluz

When we talk about the increases in prejudice in the US, we tend to focus on the election of Donald Trump. But you also found evidence of hostilities rising with the election of [Barack] Obama, when a third of white Americans were saying they were “troubled” that a black man was now in the White House.

David Williams

Yes, there is research that shows since Obama [was] elected, there has been an increase in racial prejudice and animosity — but that it was primarily [concentrated] in social media context.

Part of what created the space for Trump, and what Trump capitalized on, is the sense [white people] were losing their country and what their country represented was Obama. When Obama was elected, there were also studies coming out showing minorities will soon be the majority. So Obama’s election provided the context that helped Trump emerge as a political player.

Julia Belluz

What is different now about racism and hostility under Trump?

David Williams

What has happened with the Trump campaign is that it has built on these hostile attitudes that already existed in the Obama era.

The best evidence we have is a survey of 2,000 K-12 teachers across the US. Half of these teachers were saying their students were emboldened to use slurs and say hostile things about minorities, immigrants, and Muslims [during the 2016 election]. Two-thirds of the teachers reported that some of their students were worried about and living in the fear of what might happen to them or their families after the election.

We also drew on a national study conducted by the American Psychological Association in 2017 that finds two-thirds of all Americans were stressed about the future of the US, with nontrivial numbers reporting the outcome of the election itself has been a significant source of stress in their lives. Among minorities, more than half were reporting increased stress. Among whites, 42 percent were reporting increased stress.

Julia Belluz

What is the most relevant research that shows this tense political moment might actually sicken people?

David Williams

At the moment, we don’t have any specific studies linking this increased stress from the recent presidential election and health outcomes. But we have a lot of prior evidence suggesting that higher levels of hostility in general lead to negative health outcomes.

Researchers have gone back and used the US General Social Survey that measures the levels of racial prejudice every two years to see if areas which are higher in racial prejudice [have unique health outcomes]. They found people who live in areas that are characterized by higher levels of racial prejudice have higher rates of death. Other researchers have found the mortality rate from heart disease is higher in these [high-prejudice] areas.

Another example: In the wake of September 11, there was a well-documented increase [in] harassment and discrimination of Arab Americans in the US and anybody perceived to be Middle Eastern. And studies documented increases in mental health symptoms — higher levels of depression and anxiety — among Middle Eastern and Arab Americans at that time. That increased hostility was more intense in the six months after 9/11.

Researchers also looked at birth outcomes in the six months before 9/11 compared with the six months after. They found that among Arab-American women who give birth in the six-month period after 9/11, there was an increased rate of giving birth to babies who were low birth weight and premature. A similar pattern of increases in low-birth-weight babies and increases in premature babies was not evident for black women, native women, Latino women, or white women — only for Arab-American women.

So this period of hostility had consequences not just for the mental health of Arab Americans but also for their unborn children.

Julia Belluz

The increases in stress and anxiety — and the health fallout from that — isn’t only linked to hostility and racism but also to the threats to shrink the social safety net. So when we talk about repealing the Affordable Care Act, that may not only hurt people by taking away their health insurance — it might have negative effects on people’s overall health and well-being.

David Williams

Yes, there are proposals to eliminate Obamacare, and the current budget proposals would make large cuts to health and other social services. We don’t have to guess what might happen to health. In 1981, early in the Reagan administration, his Omnibus Budget Reconciliation Act made large cuts in the safety net. Half a million people lost health care. A million were dropped from food stamps. A million poor children lost access to reduced-price school meals.

There were lots of negative consequences. There were increases in infant mortality, more pregnant women were not getting prenatal care, there were more pregnant women with anemia, preventable childhood disease rates increased in multiple cities. And among adults with chronic health problems, there was worsening health.

[The current threat to cut the social safety net] is another layer of negative experiences that could have health consequences.

Julia Belluz

What do you expect the long-term health consequences of the current political climate to be?

David Williams

[We can see] these negative experiences have consequences not just for those adults who are experiencing them but for women who are pregnant. So they affect the next generation.

There’s also research that shows that the discrimination adolescents experience is linked to biological disregulation in their 20s. So we can see changes in stress hormones in adolescents who consistently report high levels of stress. That’s been shown in a number of studies of African-American adolescents in the US.

Julia Belluz

What do we need to do to address this?

David Williams

There may be a special role for pediatricians and child psychologists to do more outreach with our school systems. They could work with local schools to raise the awareness levels, and sensitize teachers, that this [stress] is part of a larger pattern.

We could provide training for teachers on how to respond to students when they mention one of these experiences. We also need to assist schools in the development of school-based interventions that could help them build a culture of respect and tolerance, and help schools play a role in reducing anxiety and fears, and affirming individuals who come from stigmatized backgrounds.