The nation’s largest group of pediatricians warned that racism can have devastating long-term effects on health.

A new policy statement from the American Academy of Pediatrics is the first it has issued to its members on the dangers of racism.

“If you look at what’s in the news today, in social media, on Twitter, there’s so much kids are exposed to,” said Jackie Douge, a pediatrician who co-wrote the statement. “As much as you want to keep it in the background, it’s not in the background. It’s having direct health effects on kids.”

Other pediatricians welcomed the report, which drew on 180 key studies and includes specific recommendations, and said the danger to their patients has become acute.

Their report comes amid the rise of white nationalism and racist tweets by President Donald Trump. “It’s a new age of racism,” said Nia Heard-Garris, a pediatrician at Northwestern University.

One of the main mechanisms responsible for those effects, researchers say, is the way stress wears away at people’s bodies. Experiences of discrimination can flood the body with stress hormones. And even the anticipation of discrimination can trigger the stress response. Over time, that can lead to inflammatory reactions that make the body more susceptible to disease.

Heard-Garris has studied how vicarious racism — discrimination experienced by parents — can have health consequences for their children. Two years ago, she published a review of more than 1,300 studies on racism and children’s health. Some of the impacts, she found, were more immediate, such as increased likelihood of substance abuse or obesity. But even experienced vicariously, she found, racism can threaten a child’s sense of the world as just, fair and safe.

The primary job of pediatricians is to protect children’s health, said Kyle Yasuda, president of the American Academy of Pediatrics. “It’s more than just medicine and genetic makeup. It means looking at all the determinants of health. And science has show us racism plays a part in that equation.”

The report advised its 67,000 member pediatricians to take racism into account in their practices — to be prepared to counsel families on their exposure to racism and to examine their own biases. The report calls racism “a socially transmitted disease passed down through generations, leading to the inequities observed in our population today.” It said “pediatricians are uniquely positioned to both prevent and mitigate the consequences of racism as a key and trusted source of support for pediatric patients and their families.”