Substance use and substance use disorders affect millions of Americans and have profound social and biological consequences across the life course. In the United States alone, an estimated 46 million adults had a substance use disorder in the previous year, and nearly one in four children lives with a parent who has a substance use disorder. Alcohol use disorder is the most prevalent use disorder, which affects as much as 10% of the US population.

Overdose deaths are often concentrated among working‑age adults. These deaths remain a major public health crisis. The crisis was initially driven by pharmaceutical marketing campaigns and subsequent prescribing of opioid pain medications. Many states have taken action to monitor and reduce prescribing practices and to seek legal action against opioid pain pharmaceutical manufacturers. Indeed, I was part of this legal action in the state of Oklahoma, aiding in the plan to abate the crisis. In recent years, the crisis has been driven by fentanyl use, a far more dangerous opioid. More than 100,000 drug overdoses occurred annually through 2023; however, initial projections indicate year-on-year decreases on overdose deaths in 2024 and 2025.

The loss of life from the opioid crisis reverberates through families and communities: from 2011 to 2021, more than 320,000 U.S. children lost a parent to a drug overdose. Over the decade of observation, the rate of parental loss more than doubled. Moreover, the rate of loss was more likely to impact American Indian children. These losses underscore how substance use and overdose epidemics intersect with childhood adversity and long‑term health trajectories.

This multigenerational burden of substance use and overdose is just one example of how substance use shapes the conditions of early life exposure and adversity that profoundly influence developmental pathways and health outcomes.