What are adverse childhood experiences (ACEs)?

Adverse childhood experiences, or ACEs, are potentially traumatic events that occur in childhood (0-17 years). The CDC uses ACEs to help determine different health and well-being outcomes.

ACEs are linked to chronic health problems, mental illness, and substance misuse in adulthood. ACEs can also negatively impact education and job opportunities. However, ACEs can be prevented. Examples of ACEs include:

  • Experiencing violence, abuse, or neglect
  • Witnessing violence in the home or community
  • Having a family member attempt or die by suicide

Also included are aspects of the child’s environment that can undermine their sense of safety, stability, and bonding such as growing up in a household with:

  • Substance misuse
  • Mental health problems
  • Instability due to parental separation or household members being in jail or prison


ACEs are common. About 61% of adults surveyed across 25 states reported that they had experienced at least one type of ACE, and nearly 1 in 6 reported they had experienced four more more types of ACEs.

Some children are at greater risk than others. Women and several racial/ethnic minority groups were at greater risk for having experienced four or more types of ACEs.

ACEs in Nevada – University of Nevada, Reno

Grey: Middle School Students | Blue: High School Students
Nevada Statewide Middle School and High School ACE Scores as measured by YRBS
Grey: Middle School Students | Blue: High School Students

Risk and protective factors and how they play into ACEs

The roots in the figure above depict the environmental determinants (or risk factors) that increase the risk for an ACE, whereas the leaves represent exposure to ACEs. Treating these upstream factors (the roots) will lead to fewer children experiencing and reporting ACEs (the leaves).

Some populations are more vulnerable to experiencing ACEs because of the social and economic conditions in which they live, learn, work and play. The CDC-Kaiser Permanente Adverse Childhood Experiences (ACE) Study shows a graded dose-response relationship between ACEs and negative health and well-being outcomes. In other words, as the number of ACEs increases so does the risk for negative outcomes.

In 1998, the CDC Kaiser Permanente ACE Study identified 10 ACEs. The study found that adults with an ACE score of 4 or more were at significantly higher risk for many behavioral, physical, and mental health issues later in life, including:

  • Smoking
  • Substance misuse
  • Lack of physical activity
  • Missing work
  • Obesity
  • Depression
  • Diabetes
  • Suicide attempts
  • STDs
  • Chronic lung disease
  • Stroke
  • Cancer
  • Heart disease
  • Broken bones

Risk factors are events or experiences that potentially lead to children experiencing ACEs. Risk factors for ACEs include:

  • Physical, emotional, sexual abuse and neglect
  • Mental illnesses
  • Incarceration
  • Domestic abuse
  • Substance misuse
  • Divorce
  • Poverty
  • Homelessness
  • Violence

Protective factors are events or experiences that help people more effectively deal with stressful events. These can help mitigate the development of ACEs. Protective factors include:

  • Healthy relationship from parents
  • Supporting and safe social environment
  • Resilience among individuals, families, and communities with whom individuals live and interact
  • Help in identifying and cultivating a sense of purpose
  • Stable housing environment
  • Investment into educational opportunities
  • Socioeconomic advantages

How do you use ACEs for prevention?