Gun homicides are driving down life expectancy rates among young black Americans — nearly twice as much as their white counterparts, according to a new Boston University study.

Black Americans lost 4.14 years of average life expectancy due to gun violence — both homicide and suicide — while white Americans lost 2.23 years to those causes of death, researchers found, according to the study published in BMJ Evidence-Based Medicine.

“The magnitude of it was very stark,” said Dr. Bindu Kalesan, a co-author of the study and assistant professor of medicine at Boston University School of Medicine. She said the study is the first of its kind to assess the gravity of firearm mortality among blacks.

Kalesan and her team of researchers didn’t expect to see such a large gap in the overall loss of life expectancy, she said.

Most of the deaths are occurring before 20 years of age, she said.

“They’re dying very young,” said Kalesan, adding, “Once you see this kind of disparity, you ask, what can we do and what have we done before?”

Kalesan said her team’s work serves as a “check,” suggesting researchers need to revisit the work that’s been done on gun violence — which she said isn’t enough — and plan future studies.

Kalesan collected and analyzed data from the Centers for Disease Control and Prevention over a 15-year period from 2000 to 2016 to create the study. Now she is hoping the study can serve as a wake-up call to address gun laws.

“The government should feel that they should do something about it. It should be a priority,” said Kalesan. She is pushing for more federal policies aimed at reducing gun violence along with the implementation of tailored prevention programs.

“Our advocacy groups have more to do. Let’s not put all our eggs into the same basket of politics. We have work to do to reduce gun violence,” said Kalesan.

The study also notes a disparity among black and white Americans when it comes to suicide deaths. Life expectancy loss due to suicide was higher in whites, who lost 1.62 years while blacks lost just over a half year.

But that was offset by black youths’ loss in years due to gun homicide. Blacks lost 3.41 years while whites only lost about a half year.

Kalesan predicted that future studies will find other minorities similarly face decreased life expectancy due to gun violence.

“We are going to paint a much grimmer picture here with new data,” she said.