Your Number Story

The Science
of ACEs

The landmark study that started it all

The landmark Centers for Disease Control & Prevention (CDC)-Kaiser Permanente Adverse Childhood Experiences (ACE) Study in the mid-1990s proved the link between ACEs and the increased probability of disease, disability, and adverse life outcomes. Hundreds of subsequent studies in the decades since have broadened the scope and deepened our understanding of ACEs.

Three big takeaways from decades of research that revolutionized the way we look at childhood adversity are:

  • A LOT OF US EXPERIENCE ACES.

About two-thirds of the 17,000 adults in the original study had experienced at least one of the ten ACEs identified in the study, and over a third had experienced two or more. It also showed that ACEs affect all communities, regardless of race, culture, or socio-economic status. Later studies showed some populations are more greatly affected than others.

  • TOXIC STRESS CHANGES OUR BODIES.

Toxic stress literally changes a child’s brain and body in ways that can increase our risk of illness, and make life more challenging, whether or not we’re engaging in high-risk behaviors.

  • THE EFFECTS OF ACES ARE CUMULATIVE.

The higher our number, the greater the probability we may experience the effects. ACEs are strongly associated with 9 out of the 10 leading causes of death in the U.S. and over 40 common health conditions.

A paradigm shift

The discovery of a link between ACEs and the probability of negative health – and life — outcomes prompted a paradigm shift. Childhood adversity could no longer be swept under the rug; it affects so many of us, can have serious short and long-term impacts, and is heavily influenced by systemic factors and our living conditions. The effects of toxic stress brought on by ACEs have societal, health and well-being, and economic costs that affect millions of people and cost billions of dollars in the United States alone. 

Original CDC-Kaiser Permanente ACE study

The Centers for Disease Control & Prevention (CDC)-Kaiser Permanente Adverse Childhood Experiences (ACE) Study is one of the largest investigations of childhood abuse and neglect and household challenges and later-life health and well-being. The ACEs Study was conducted in the mid-1990s involving over 17,000 Southern California Kaiser adult members. If you’d like to learn more about the original study, explore the link below:

Dr. Nadine Burke Harris' TED Talk: How childhood trauma affects health across a lifetime

In this fascinating TED Talk, Dr. Nadine Burke Harris — our advisor and California’s Surgeon General — explores how childhood trauma and toxic stress can have real, tangible effects on a child’s brain and biology, with ramifications that span a lifetime.

ACEs are more than a
personal problem. They’re
a public health crisis. 

In the decades since the CDC-Kaiser study, dozens of additional studies have confirmed the science and given us a more complete understanding of ACEs (which continues to unfold). The respondents in the original study, for instance, were mostly middle-class, college educated white people, and the adverse childhood experiences measured were limited to a specific set of ten.

More recent studies have found a higher rate of ACEs in marginalized communities. Other studies have explored broader definitions of other common childhood adversities to include factors like community violence, racism, and discrimination.

Roadmap for Resilience Executive Summary

The California Office of the Surgeon General released a comprehensive Roadmap for Resilience on ACEs, toxic stress, and health in 2020. This Executive Summary provides a solid overview of the general science behind ACEs and toxic stress.

Among the major points: 

ACES AND TOXIC STRESS CARRY A HIGH COST IN TERMS OF HEALTH.

ACEs are strongly associated with 9 out of 10 of the leading causes of death in the United States, and risk increases with each category a child is exposed to.

ACES AND TOXIC STRESS CARRY A HIGH COST FOR SOCIETY.

The report estimates that ACE-related healthcare expenses may cost over $1.2 trillion over the next 10 years in California alone. And that’s only looking at eight of the most common ACE-associated health conditions.

ACES IMPACT ALL COMMUNITIES, BUT SOME POPULATIONS ARE AFFECTED MORE.

Additional studies have shown a higher prevalence of ACEs in marginalized communities and cultures, such as those most impacted by racism and poverty.

SEVERAL ACE-ASSOCIATED HEALTH CONDITIONS (LIKE HEART DISEASE, DIABETES, AND OBESITY) INCREASE RISK OF ADVERSE OUTCOMES WITH COVID-19.

A BLUEPRINT FOR ADDRESSING ACES.

  • This first California Surgeon General’s report lays out a public health approach for preventing ACEs and healing toxic stress through prevention, early detection, and early intervention. This report gives sector-specific and cross-sector suggestions for healthcare, public health, social services, early childhood, education, and justice systems.