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ACEs Adverse Childhood Experiences

ACEs are adverse childhood experiences that can harm a child’s development, health, and future outcomes. However, understanding, addressing, and avoiding ACEs can promote healthier development and avoid negative impacts on adults.

What are ACEs?

ACEs stands for adverse childhood experiences. They are potentially traumatic events experienced by children from 0 to 17 years old and are preventable. ACEs are categorized into three groups: child abuse, neglect, and dysfunctional households. Numerous studies have found that childhood trauma and lifelong effects can result from these experiences if unresolved.​1​

girl sitting on couch burying face into hands

How common are adverse childhood experiences?

ACEs are common, according to the most extensive ACE study conducted by the Centers for Disease Control and Prevention (CDC) and Kaiser Permanente from 1995 to 1997. 64% of the participants experienced at least one ACE, and almost 13% had four or more ACEs during childhood.​2​

What are the 10 ACEs of trauma?

Here is the adverse childhood experiences list with the 10 ACEs grouped into three categories.​3​


  • Emotional abuse is defined as a parent, stepparent, or adult living in your home who swore at you, insulted you, put you down, or acted in a way that made you afraid that you might be physically hurt.
  • Physical abuse is defined as a parent, stepparent, or adult living in your home who pushed, grabbed, slapped, threw something at you, or hit you so hard that you had marks or were injured.
  • Sexual abuse is defined as an adult, relative, family friend, or stranger who was at least 5 years older than you who touched or fondled your body in a sexual way, made you touch his/her body in a sexual way, attempted to have any type of sexual intercourse with you.

Household Dysfunction

  • Violently treated household member: Your parent or step-parent was pushed, grabbed, slapped, had something thrown at her, kicked, bitten, hit with a fist, hit with something hard, repeatedly hit for at least a few minutes, or ever threatened or hurt by a knife or gun by your father (or stepfather) or mother’s boyfriend.
  • Substance abuse in the household: A household member was a problem drinker or alcoholic, or a household member used street drugs.
  • Mental illness in the household: A household member was depressed or mentally ill, or a household member attempted suicide.
  • Parental separation or divorce: Your parents were separated or divorced.
  • Incarcerated household member: A household member was in prison.


  • Emotional neglect: Someone in your family never or rarely helped you feel important or special, you never or rarely felt loved, people in your family never or rarely looked out for each other and felt close to each other, or your family was never or rarely a source of strength and support.
  • Physical neglect: There was never or rarely someone to take care of you, protect you, or take you to the doctor if needed. You didn’t have enough to eat, and your parents were too drunk or too high to take care of you, or you had to wear dirty clothes.

What are conventional ACEs?

The 10 ACEs categorized into three groups in the original 1995 study are the conventional ACEs. A study in 2015 expanded the definitions of ACEs to include adversities such as racism, witnessing violence, unsafe neighborhoods, bullying, and having lived in foster care.​4​

What are the 4 types of ACEs?

The 4 types of ACEs are abuse, neglect, household dysfunction, and expanded ACEs.

What are the 7 categories of ACEs?

The 7 categories of ACEs that are monitored and surveyed across all 50 states are physical abuse, emotional abuse, sexual abuse, exposure to domestic violence, substance use within the household, mental illness in the family, parental separation or divorce, and having a household member who is incarcerated.​5​

What is the most common adverse childhood experience?

The most common ACE was physical abuse (28.3%) in the 1995 CDC-Kaiser study, followed by substance abuse in the household (26.9%), and parental separation or divorce (23.3%).

Subsequent studies from 2011 to 2020 showed that the most common ACE was parental separation (28.4%), followed by household substance use (26.5%) and physical abuse (23.3%).​5​

Adverse childhood experiences questionnaires

Here are some ACEs questionnaires to measure ACEs.

The original version of these questionnaires can be found at

What are the impacts of ACEs?

Research has found that people who have experienced four or more aversive childhood experiences are more at risk of the following.​2​

  • 4- to 12-times increased risks for alcoholism, drug use, depression, and suicide attempts.
  • 2- to 4-times increased in smoking, poor lifelong health, more than 50 sexual intercourse partners, and sexually transmitted diseases.
  • 1.4- to 1.6- times increased in physical inactivity and severe obesity.

How do adverse childhood experiences impact health and outcomes throughout a person’s life?

Adverse childhood experiences have a lifelong impact on a person’s health and outcomes by inducing a state of long-term stress, also known as toxic stress. Toxic stress can trigger the activation of the stress response system in the brain excessively.

Extreme stress pushes the brain into survival mode. Over time, the brain gets stuck in this high-alert state and can no longer distinguish between mildly stressful events and life-threatening ones or return to a relaxed state after dangers have disappeared. Resilience in children is reduced when toxic stress is experienced without supportive relationships with adults.

Disrupted brain development can affect a child’s social, emotional, and cognitive development. It can also affect a child’s immunity and gene expression (epigenetics). The negative effects on an individual’s physical health and mental health can continue into adulthood, resulting in chronic diseases, disability, social problems, and early death.​6​

Common adult diseases include cancer, heart disease, posttraumatic stress disorder (PTSD), depression, bipolar disorder, behavioral disorder, and anxiety.

How to prevent adverse childhood experiences

Prevention is the best way to help children avoid child trauma. Here are the six strategies for preventing ACEs identified by the National Center for Injury Prevention and Control.​7​

  • Strengthen economic support for families experiencing material hardship to reduce the sources of stress.
  • Promote social norms that protect against violence toward kids.
  • Affordable supportive services, such as child care and early childhood education
  • Enhance core life skills in parents and children, such as emotional regulation, to handle stress in everyday life.
  • Connect children to caring adults and mentors.
  • Screen, identify, and intervene in adverse childhood experience exposures.

Parents play an important role in preventing ACEs with the following steps.

Seek help with mental health or substance issues

For parents who are grappling with mental health conditions or substance use disorders, seeking help is a critical step for their well-being and the health and safety of their children.

Learn positive parenting skills

Parenting is a complex and demanding job. Parental stress can significantly impact how we act, sometimes leading us to default to the parenting styles we experienced as children. Unfortunately, this can mean reverting to strict or harsh parenting practices that, while not intended to harm, can inadvertently contribute to ACEs experienced by our children. 

Recognizing one’s parenting style and learning positive discipline skills can help parents avoid repeating the trauma cycle they grew up in.

Create positive experiences

Positive childhood experiences are protective factors against ACE exposure and intergenerational transmission of trauma.​8​

Think flexibly

Psychological flexibility allows parents to stay open to trying different parenting methods and tuning into what each child needs. Find what works best for each kid because they’re all different, and what helps one child thrive might not be the same for another.

Prioritize self-care

A well-rested, healthy parent is better equipped to handle parenting challenges with patience and empathy. This is often easier said than done, given the relentless demands and daily hassles of raising children. Therefore, parents must consciously prioritize their well-being.

Be a good enough parent

Parents often feel pressure to be perfect, but being a good enough parent is good enough.

How to help a child with adverse childhood experiences

Helping a child with ACEs requires a compassionate and trauma-informed approach

Here’s how you can support a child’s healing and healthy child development.

  1. Understand Trauma and Behavior – Recognize that behavior problems in children with trauma are often coping mechanisms developed in response to their adverse experiences. Approach these effects of child abuse with empathy and patience.
  2. Establish Safety – Create a safe and predictable environment. Be responsive to the child’s needs, set clear boundaries, and maintain consistency in your parenting.
  3. Build Trust in Relationships – Use trust-based discipline strategies. Teach through reasoning, focus on relationship-building, and take proactive steps to prevent disruptive behavior. Repair trust when it’s broken by making amends.
  4. Develop Emotional Regulation – Model emotional regulation yourself. Validate the child’s feelings, help co-regulate their emotions, and teach them about different emotions and coping with them.
  5. Speak the Unspeakable – Encourage abused children to communicate openly about their traumatic experiences. Create a safe space for the child to discuss their trauma, which is crucial for their healing process.
  6. Recovery and Self-Care – Support the caregivers’ mental well-being. Caregivers should practice self-care as their mental health issues significantly impact the child’s recovery.
  7. Advocate & Coordinate – Advocate for the child with clinicians and coordinate with schools to ensure others understand the child’s behaviors through a trauma-informed lens.

How to overcome adverse childhood experiences as an adult

Recognizing and acknowledging any trauma from one’s childhood is an important first step in healing. Securing appropriate support is next. 

Despite research indicating that nearly two-thirds of individuals have experienced at least one ACE, the topic of attachment trauma and the negative outcome of ACEs often remains shrouded in silence in social contexts. There is a widespread lack of awareness about what constitutes ACEs. Therefore, it’d be easier to begin your healing journey by establishing a foundation of support, starting with an experienced mental health professional.

Also See: Childhood Trauma Symptoms in Adults




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    Boullier M, Blair M. Adverse childhood experiences. Paediatrics and Child Health. Published online March 2018:132-137. doi:10.1016/j.paed.2017.12.008
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    Felitti VJ MD, FACP, Anda RF MD, MS, Nordenberg D MD, et al. Relationship of Childhood Abuse and Household Dysfunction to Many of the Leading Causes of Death in Adults. American Journal of Preventive Medicine. Published online May 1998:245-258. doi:10.1016/s0749-3797(98)00017-8
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    . About the CDC-Kaiser ACE Study. CDC.
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    Cronholm PF, Forke CM, Wade R, et al. Adverse Childhood Experiences. American Journal of Preventive Medicine. Published online September 2015:354-361. doi:10.1016/j.amepre.2015.02.001
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    Swedo EA, Aslam MV, Dahlberg LL, et al. Prevalence of Adverse Childhood Experiences Among U.S. Adults — Behavioral Risk Factor Surveillance System, 2011–2020. MMWR Morb Mortal Wkly Rep. Published online June 30, 2023:707-715. doi:10.15585/mmwr.mm7226a2
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    McEwen BS. Neurobiological and Systemic Effects of Chronic Stress. Chronic Stress. Published online February 2017:247054701769232. doi:10.1177/2470547017692328
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    Jones CM, Merrick MT, Houry DE. Identifying and Preventing Adverse Childhood Experiences. JAMA. Published online January 7, 2020:25. doi:10.1001/jama.2019.18499
  8. 8.
    Narayan AJ, Lieberman AF, Masten AS. Intergenerational transmission and prevention of adverse childhood experiences (ACEs). Clinical Psychology Review. Published online April 2021:101997. doi:10.1016/j.cpr.2021.101997


    * All information on is for educational purposes only. Parenting For Brain does not provide medical advice. If you suspect medical problems or need professional advice, please consult a physician. *