Trauma early in life could have a detrimental effect on a child’s biological makeup, possibly paving the way for heart disease and other chronic illnesses, NPR reported this week.

Two-thirds of American children are exposed to some kind of extreme stress in their adolescence, according to the article, including stress triggered by a divorce, abuse and death. That kind of weight, Nadine Burke Harris, MD, said, “literally gets under our skin.”

“When kids are exposed to very high levels of chronic stress or adversity—or really intense and scary experiences—it actually changes the way their brains and bodies are wired,” she told NPR. “And that can lead to changes in brain development, changes in the development of the immune system, our hormonal systems and even all the way down to the way our DNA is read and transcribed.”

Since stress can alter the way DNA is read and replicated, it can also trigger a slew of dangerous diseases, including cancer, diabetes, stroke, heart disease and Alzheimer’s.

Read NPR’s full interview with Burke Harris here: